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Commercial Lock Function Codes Guide: ANSI F75 to F110 Explained for Schlage ND and L Series Friday, July 24, 2026

ANSI lock function codes describe exactly how a lock operates, independent of manufacturer. Cylindrical locks (ANSI A156.2) use F75 through F110. Mortise locks (ANSI A156.13) use F01 through F30. The same functional behavior has different codes in each system: F84 cylindrical equals F05 mortise (both classroom function). Specifying F84 for a mortise lock is a common error. Key functions: F75/F01 passage (no locking), F76/F19 privacy (inside privacy button, emergency key outside), F82/F04 office (push button inside, key outside), F84/F05 classroom (key locks outside lever from corridor only), F86/F07 storeroom (outside lever always rigid, key to enter), F110 classroom security intruder (inside key locks outside lever from inside, no corridor exposure during lockdown). Functions are factory-set and cannot be changed in the field.

A hardware schedule is only as useful as the person reading it can interpret its function codes. Ordering an F82 (office function) instead of an F86 (storeroom function) for a pharmaceutical storage room eliminates the security the room was designed to provide. Ordering an F84 classroom function on a school project in a state with classroom security laws fails the inspection and generates a hardware change order that costs multiples of the difference in lock price. This guide explains every major ANSI function code, the cylindrical vs mortise numbering discrepancy that causes the most specification errors, the Schlage ND Series suffix system, and the classroom function evolution from F84 to F110 that affects every K-12 project.

Browse Schlage commercial lock parts by function at SecurityParts.com: Schlage ND Series and ALX Series cylindrical lock parts, Schlage L Series mortise lock parts, Schlage commercial hardware catalog, and the complete Allegion parts catalog.

F84 not F05 Most common error: specifying cylindrical classroom code for a mortise lock application. Mortise classroom is F05.

Factory-set Lock functions are set at manufacturing. Field conversion requires complete lock chassis replacement, not field adjustment.

F110 Classroom security intruder: inside key locks outside lever without corridor exposure. Required by many state school security laws.

F86 only Storeroom function: outside lever permanently rigid. The only function with no passage mode. Cannot be set to free-swing.

Why ANSI Function Codes Exist and How the System Works

The ANSI lock function code system was created to allow hardware schedules to specify door lock behavior without requiring the specifier to name a particular manufacturer. An architect writing a hardware schedule can specify "F84 classroom function, Grade 1, 2-3/4 inch backset" without selecting a brand. The general contractor can then source that function from any BHMA-certified manufacturer because the behavior is standardized.

This works because ANSI function codes describe the mechanical behavior from the perspective of the occupant: which lever is free, which requires a key, what a push button or toggle does, and what state the lock is in when no action has been taken. The internal mechanism that produces this behavior varies by manufacturer, but the behavior it produces is consistent across all BHMA-certified products with the same function code.

The Two Numbering Systems: Cylindrical vs Mortise

This is where most hardware schedule errors originate. Cylindrical locks (bored locks, ANSI A156.2) and mortise locks (ANSI A156.13) use completely separate numbering systems for the same functional behaviors:

Function Name	Cylindrical Code (A156.2)	Mortise Code (A156.13)	Schlage ND Suffix	Schlage L Series Suffix
Passage	F75	F01	ND10	L9010
Privacy	F76	F19	ND40	L9040
Office / Entrance	F82	F04	ND44	L9044
Classroom	F84	F05	ND70	L9070
Storeroom	F86	F07	ND80	L9080
Asylum / Institution	F87	F30	ND82	L9082
Vestibule / Apartment	F88	F09	ND60	L9060
Classroom Security (Intruder)	F110	F32/F33	ND78	Varies

A hardware schedule that lists "F84 classroom" for a door with a mortise lock is an error. The correct code for a mortise classroom function is F05. If you order a Schlage L9070 (mortise classroom) when the schedule says F84, the product is correct but the specification contains a cylindrical code applied to a mortise product. The mortise equivalent of F84 is always F05.

Non-Keyed Functions: Passage and Privacy

F75 / F01 Passage Function Cylindrical F75 | Mortise F01 | Schlage ND10 / L9010

What it does

Both levers always retract the latch. There is no locking mechanism. The door can be pushed open from either side without any key, credential, or action. The latch retracts when either lever is turned.

Where it is used

Interior corridor doors that do not require any locking (open office areas, non-secured stairwells, maintenance corridors). Passage function is also the "unlocked mode" that some other functions (like F82 office) can be toggled into.

Outside lever

Always free

Inside lever

Always free

F76 / F19 Privacy Function Cylindrical F76 | Mortise F19 | Schlage ND40 / L9040

What it does

Inside trim has a push button or thumbturn that engages a bolt or lever-blocking mechanism, preventing the outside lever from operating. When the inside privacy device is engaged, the outside lever is locked. An emergency key (or a tool through an emergency hole in some cylindrical versions) allows emergency entry from outside. The inside lever always retracts the latch for egress.

Where it is used

Restrooms, individual offices where the occupant needs privacy without a key, fitting rooms, healthcare exam rooms. The emergency key feature satisfies life safety requirements by ensuring the occupant can never be permanently trapped inside.

Outside lever

Locked when privacy is engaged; free otherwise

Inside lever

Always free; privacy device engages inside

Medium-Security Keyed Functions: Office and Entrance

F82 / F04 Office / Entrance Function Cylindrical F82 | Mortise F04 | Schlage ND44 / L9044

What it does

Both levers retract the latch unless the outside lever is locked by a push button on the inside face of the lock or by a key from outside. When the push button is engaged, the outside lever is locked. Turning the inside lever OR inserting and turning the key from outside unlocks the push button and restores free operation. The inside lever is always free for egress regardless of push button state.

Where it is used

Individual offices that need to be locked during meetings or after hours. The push button allows occupants to lock the office from inside without a key, and a single lever operation (from inside) releases the lock. The key from outside is the entry method when the office is unoccupied and locked.

The security gap that F82 creates in some applications

F82 has a push button inside. When the office is unoccupied and locked, the outside lever is secure. But the push button means any person who knows about it can lock the door from inside to prevent access by authorized staff. In high-security or healthcare applications where staff must always have access, F82's inside push button is a vulnerability. F84 or F86 should be specified instead of F82 when inside lock control by unauthorized occupants is a concern.

Outside lever

Free or locked by push button (inside) / key (outside)

Inside lever

Always free; also unlocks push button

High-Security Keyed Functions: Classroom and Storeroom

F84 / F05 Classroom Function (Traditional) Cylindrical F84 | Mortise F05 | Schlage ND70 / L9070

What it does

Both levers retract the latch unless the outside lever is locked. The outside lever is locked or unlocked by inserting and turning a key in the outside lever cylinder from the corridor side. The inside lever is always free for egress. There is no push button or toggle inside: the function cannot be changed from inside the room.

How the passage mode works

When a key is turned in the outside cylinder, it toggles the outside lever between locked and passage mode. In passage mode, both levers retract the latch freely. This is how classrooms are set for the school day: a staff member with a key uses the outside cylinder to put the lock in passage mode in the morning and locked mode at the end of the day.

The lockdown limitation

In F84/F05, the outside lever can only be locked from outside the room (in the corridor). During an active threat lockdown, a teacher must open the door and expose themselves to the corridor to lock the outside lever. This is the safety gap that F110 was designed to eliminate.

Outside lever

Free (passage) or locked, toggled by key from outside only

Inside lever

Always free; cannot control outside lever

Browse Schlage ND70 Series F84 classroom cylindrical lock parts and Schlage L9070 F05 classroom mortise lock parts at SecurityParts.com.

F86 / F07 Storeroom Function Cylindrical F86 | Mortise F07 | Schlage ND80 / L9080

What it does

The outside lever is permanently rigid. It cannot be turned under any condition from outside without a key. A key in the outside cylinder simultaneously retracts the latch and allows the lever to turn, providing entry. The inside lever is always free for egress. There is no passage mode, no push button, and no toggle: the outside lever cannot be placed in a freely operable state.

Why F86 is the correct specification for secured storage

F82 (office function) has an inside push button that can lock the door, but the outside lever can also be in a freely operable (unlocked) mode when the push button is not engaged. Any time the room is occupied without the push button engaged, the door is freely accessible from outside. F86 has no unlocked mode for the outside lever: the room is always key-access from the outside, whether occupied or not. This eliminates the risk of someone propping the door open or forgetting to engage the push button, leaving a secured room temporarily accessible.

Applications

Pharmaceutical storage, server rooms, cash rooms, records storage, electrical and mechanical rooms, evidence rooms, any space requiring key control at all times. Also the correct function for emergency stairwell doors in buildings requiring key-controlled stair reentry.

Outside lever

Always rigid; key required for entry at all times

Inside lever

Always free for egress

Browse Schlage ND80 Series F86 storeroom cylindrical lock parts at Security Parts.

Classroom Security: The F84 to F110 Evolution

The original F84/F05 classroom function was designed for a different threat environment: keeping students from locking each other out of classrooms, not protecting teachers during active threat events. After Sandy Hook (2012) and subsequent legislative action across multiple states, a new classroom security function was needed that allowed inside lockdown without corridor exposure.

F110 / F32-F34 Classroom Security / Intruder Function Cylindrical F110 | Mortise F32/F33/F34 | Schlage ND78

What it does

Both levers retract the latch in the unlocked state. A key in either lever (inside or outside) locks or unlocks the outside lever. The inside lever remains free for egress at all times regardless of outside lever state. This allows a teacher inside the room to lock the outside lever using their key in the inside cylinder, without opening the door or entering the corridor.

How lockdown works with F110

During an active threat: teacher inserts key in inside cylinder, rotates 180 degrees counterclockwise, removes key. Outside lever is now locked. Door is secured from inside without any corridor exposure. To unlock: key in either lever, 180 degrees clockwise.

State classroom security law requirements

Many states have enacted classroom security legislation following mass shooting events at schools. California SB 1384 and similar laws in other states require classroom locks to allow locking from inside the room without opening the door. This effectively mandates F88, F90, or F110 functions. Specifying F84 on a school project in a state with these requirements results in a failed inspection and a hardware change order. Always verify state and AHJ requirements before finalizing the function code on any K-12 project.

Outside lever

Locked/unlocked by key from either side

Inside lever

Always free; inside cylinder locks outside lever

The Schlage ND78 Know It's Locked indicator that no competitor documents at the ordering level: The Schlage ND78 (F110 classroom security function) has a 180-degree visibility window on the inside trim that shows a "locked/unlocked" status. Staff can see the outside lever lock status from across the room without approaching the door. This indicator was added specifically because the original F84 classroom function had no visual indication: during a lockdown, the teacher had to approach the door and test the handle to verify the lock was engaged. The ND78's indicator resolves this. When specifying ND78 (F110) for school projects, note the indicator explicitly in the hardware schedule as a separate item if it is required, since the Vandlgard indicator option is sometimes ordered separately.

F88/F09 Vestibule Function: The F110 Alternative for Apartment and Vestibule Applications

F88 (cylindrical vestibule) and F09 (mortise vestibule) allow the inside lever to lock the outside lever, but the inside lever also always allows egress. F88 is similar to F110 but the inside cylinder operation differs slightly: in F88, the inside key or toggle controls the outside lever, while in F110, a key in either lever controls the outside lever. F88 is also specified for apartment corridors and building vestibules where residents need to lock the corridor-side lever from inside their unit. In some school security applications, F88 is accepted where F110 is not specifically required.

Maximum Security and Specialty Functions

F87 / F30 Asylum / Institution Function Cylindrical F87 | Mortise F30 | Schlage ND82 / L9082

What it does

Both levers are always rigid. Neither lever can retract the latch from either side under any condition without a key in the respective cylinder. A key in the outside cylinder retracts the latch for entry. A key in the inside cylinder retracts the latch for egress. No lever-based egress is available.

Where it is used

Behavioral health facilities, psychiatric units, secure detention areas, and any environment where free egress capability (the ability to open the door from inside without a key) is not required or would compromise patient or inmate management. This is the most restrictive function: it eliminates the "inside lever always free" that all other functions maintain.

Life safety critical: F87/F30 eliminates free egress from inside. Every other major ANSI function maintains free inside lever egress. F87/F30 does not. This function requires AHJ approval and compliance with life safety code provisions for locked egress (NFPA 101 controlled egress in healthcare, for example). It must never be installed without confirming the specific occupancy type and applicable code section permits locked egress.

Schlage ND Series Function Suffix Quick Reference

ND Suffix	ANSI Function	Common Name	Inside Lever	Outside Lever
ND10	F75	Passage	Always free	Always free
ND40	F76	Privacy	Free; privacy thumbturn	Locked when privacy engaged
ND44	F82	Office / Entrance	Always free; push button	Free or locked by push button
ND70	F84	Classroom	Always free; no lock control	Locked/unlocked by key from outside only
ND78	F110	Classroom Security	Free; inside key locks outside	Locked/unlocked by key from either side
ND80	F86	Storeroom	Always free	Always rigid; key only
ND82	F87	Institution / Asylum	Rigid; key to exit	Rigid; key to enter
ND60	F88	Vestibule / Apartment	Free; inside key locks outside	Locked by inside key; key from outside

Browse Schlage ND Series parts by function suffix at Security Parts.

Five Specification Errors That Generate Hardware Change Orders

Error 1: Writing F84 (cylindrical code) in a mortise lock hardware schedule

F84 is a cylindrical lock code. The mortise lock classroom function is F05. A hardware schedule listing F84 for mortise lock openings contains a cross-standard error that may not be caught until the product arrives.

Fix: Always use the standard-specific code: F84 for cylindrical (ND70 from Schlage), F05 for mortise (L9070 from Schlage). Cross-reference the table above when moving between cylindrical and mortise specifications.

Error 2: Specifying F84 on a K-12 school project in a state requiring F110

F84 does not allow inside lockdown without corridor exposure. Many states now require F88, F90, or F110 for classroom doors. A failed inspection generates a change order that costs more than the specification verification would have.

Fix: Verify applicable state classroom security code and AHJ requirements before finalizing the function code on any K-12 project. When in doubt, specify ND78 (F110) and note the inside indicator requirement separately.

Error 3: Specifying F82 (office function) for secured storage rooms

F82 has a push button inside that allows occupants to lock the door from inside. In an unoccupied secured room with F82, the push button must be engaged for the room to be secure. If an occupant leaves without engaging the push button, the room is freely accessible until someone re-locks it.

Fix: Specify F86 (ND80) for any room requiring key-controlled access at all times. F86 has no unlocked mode for the outside lever: the room is always key-entry from outside regardless of occupancy or push button state.

Error 4: Assuming the function can be changed in the field

A contractor ordering the wrong function and planning to "convert it in the field" will find that most cylindrical lock functions cannot be converted without replacing the entire chassis. The latch, cam, and spindle configuration is factory-set.

Fix: Order the correct function code from the hardware schedule before the product ships. If there is uncertainty about the correct function, call SecurityParts.com at 845-935-0301 for function code verification before ordering.

Error 5: Specifying F87 (asylum function) without AHJ approval for locked egress

F87 eliminates the inside lever's free egress function. Both levers require a key. This is not permitted in most occupancies without specific code compliance documentation and AHJ approval for controlled or locked egress arrangements.

Fix: Confirm the specific NFPA 101 or IBC code section that permits locked egress for the occupancy type before specifying F87. Document the code basis for the function selection on the hardware schedule.

Why Choose Security Parts for Schlage Commercial Lock Parts

Cylindrical vs mortise code discrepancy documented, F110 classroom security law context, ND78 inside indicator detail, function change impossibility explained, and same-day OEM shipping.

Cross-Standard Code Reference

We document the cylindrical vs mortise function code discrepancy that causes the most hardware schedule errors. F84 is cylindrical classroom. F05 is mortise classroom. Confusing them generates wrong-product orders on projects with mortise lock specifications.

F110 State Law Context

We document that many states now require inside-locking classroom capability (F88/F90/F110) and that specifying F84 on school projects in these states results in failed inspections. This fact is absent from all competitor parts supplier content.

F82 Storage Room Risk

We document the F82 push-button vulnerability in storage rooms: F82 has an unlocked mode that F86 does not. Pharmaceutical storage and high-value rooms specified as F82 instead of F86 have a security gap that is never documented at the parts ordering level.

Same-Day OEM Shipping

Schlage ND Series and L Series parts by function ship same day from US warehouses. Call 845-935-0301 or the contact page for function code verification before ordering.

What Makes Security Parts Different for Commercial Lock Function Parts

We document the cylindrical vs mortise ANSI function code numbering discrepancy and its cross-reference table. F84 for a mortise lock application is wrong: the mortise classroom function is F05. This is the single most common hardware schedule error and is documented nowhere in competitor parts content.
We document the state classroom security law context for F110: specifying F84 on school projects where state law requires inside-locking capability fails inspection and generates change orders. No competitor documents this at the parts purchasing level.
We document the F82 push-button vulnerability: F82 can be in an unlocked mode. F86 cannot. Secured storage rooms specified as F82 instead of F86 have a security gap that no other parts supplier documents.
We document the Schlage ND78 Know It's Locked indicator as a lockdown status verification tool. The indicator allows staff to confirm outside lever lock status from across the room without approaching the door, which is the specific improvement over F84 that addresses the lockdown verification problem.
We carry Schlage ND Series cylindrical lock parts and Schlage L Series mortise lock parts for all major ANSI function codes, alongside the Falcon commercial hardware parts catalog and complete Allegion parts catalog.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Frequently Asked Questions About Commercial Lock Function Codes

What is an ANSI lock function code and why does it matter?

An ANSI lock function code is a standardized number describing exactly how a lock operates: which lever is free, which requires a key, and what inside controls exist. The system is standardized across manufacturers so that an F84 from Schlage and an F84 from Sargent behave identically. Function codes matter because the wrong function creates either a security gap (F82 in place of F86 on a secured storage room) or a code violation (F84 on a school project requiring F110). Functions are factory-set and cannot be changed in the field without replacing the entire lock chassis.

What is the difference between cylindrical lock function codes and mortise lock function codes?

Cylindrical locks use function codes in the F75 and above range (F75, F82, F84, F86, F110). Mortise locks use function codes in the F01 through F30 range (F01, F04, F05, F07, F30). The same functional behavior has different codes in each system: F84 cylindrical equals F05 mortise (both classroom), F86 cylindrical equals F07 mortise (both storeroom). Writing F84 in a hardware schedule for a mortise lock application is a cross-standard error. Always use the code for the correct lock type.

What is the difference between the F84 classroom function and the F110 classroom security function?

F84 allows the outside lever to be locked or unlocked only from outside the classroom (corridor side). During lockdown, the teacher must open the door and expose themselves in the corridor to lock it. F110 allows either lever (inside or outside) to lock or unlock the outside lever, so the teacher can lock the door from inside without opening it or entering the corridor. Many states now require inside-locking capability (F88, F90, or F110) for classroom doors. Specifying F84 on a school project in a state requiring F110 fails the inspection.

What is the difference between the F84 classroom function and the F86 storeroom function?

F84 classroom can be toggled between locked and passage (free swing) mode by a key from outside. The room can be freely accessible when the key holder puts it in passage mode. F86 storeroom has no passage mode: the outside lever is permanently rigid and the room is always key-access from outside. F86 is the correct specification for pharmaceutical storage, server rooms, cash rooms, and any space requiring key control at all times. F84 is not appropriate for rooms that must never be in a freely accessible mode.

Can a lock function be changed in the field after installation?

For most cylindrical locks, no. The internal cam, spindle, and mechanism configuration that produces the function behavior is factory-set and cannot be rearranged in the field. Converting a Schlage ND70 (F84 classroom) to an ND80 (F86 storeroom) requires replacing the entire lock chassis. Some mortise locks offer limited field function conversion, but the base function is generally also factory-set. Order the correct function code before the product ships. Function code changes after installation typically require complete lock replacement.

How do I read the lock function column in a hardware schedule?

The function column in a hardware schedule lists either the ANSI code (F84, F86, F82) or a manufacturer-specific suffix (ND70, ND80, ND44 for Schlage ND Series). Cross-reference the suffix to the ANSI code using the manufacturer's function guide: ND70 equals F84, ND80 equals F86, ND78 equals F110. Confirm whether the schedule is specifying cylindrical or mortise hardware: the same ANSI function has different codes in each system. On school projects, verify state classroom security law requirements before accepting the scheduled function code, since many states have updated their requirements beyond F84.

details

How to Install a Door Closer on a Commercial Door Friday, July 24, 2026

This guide explains how to install a door closer on a commercial door from the first template mark to the final valve adjustment. It covers all three standard mounting positions, the manufacturer installation template, arm geometry, spring power setting, ADA compliance verification, and fire-rated door requirements. Every step applies to surface-mounted hydraulic closers, which handle the large majority of commercial door installations.

When you install a door closer on a commercial door correctly, it lasts through its rated cycle life. When installed incorrectly, it fails within months regardless of brand or quality. SecurityParts.com stocks LCN door closer parts and complete units for every commercial mounting configuration. Browse the LCN door closer parts catalog, the LCN commercial door closer selection guide, and the complete LCN brand parts catalog. Call 845-935-0301 or visit the SecurityParts.com contact page for pre-installation parts identification support.

How to Install Door Closer on Commercial Door: Key Facts Before You Begin

Installing a door closer on a commercial door correctly determines whether the device lasts through its full rated cycle life or fails within months. A commercial door closer is a hydraulic-mechanical device that controls the speed and force at which a door closes after being opened. Inside the housing, a compressed spring stores energy when the door opens. Hydraulic fluid flowing through calibrated passages governs how quickly the spring returns the door to the closed position. The result is a controlled, consistent closing arc on every cycle.

Incorrect installation of a door closer on a commercial door is one of the most common causes of premature closer failure, arm damage, and ADA non-compliance. A closer mounted in the wrong position, with the arm shoe set incorrectly, or with the wrong spring size for the door will not perform correctly regardless of how carefully the valves are adjusted afterward. Getting the physical mounting right from the start is what determines whether the closer lasts through its rated cycle life or fails prematurely.

For an overview of closer types including surface-mounted, overhead concealed, and floor spring models, see the commercial door closers types guide at SecurityParts.com before selecting the closer for your application.

Tools Required Before You Begin

Electric drill with 3/16" and 7/32" bits for hollow metal; appropriate wood bits for solid wood doors

Center punch and hammer to prevent drill walking on metal door faces

Tape measure and pencil for centerline height marking

Level to confirm the closer body is mounted straight

Phillips and flathead screwdrivers for body and arm bracket screws

3/32" hex key for valve adjustment after installation

5/32" hex key for spring power adjustment on LCN 4040XP external dial

Door pressure gauge for ADA opening force verification

Stopwatch for ADA closing speed verification (5-second minimum)

Second person to hold the door open during arm attachment

Close the backcheck valve completely before attaching the arm. This is the step most installation guides skip entirely. Opening a door with the backcheck valve open and no arm resistance allows the door to be swung open with no damping at all. This can damage the closer body, the arm, and the frame on the first cycle. Before connecting the arm to the closer, turn the backcheck (B) valve fully clockwise to the seated position. Set the backcheck after the arm is connected and the door is cycling normally.

Safety Precautions

Never work alone on a heavy commercial door. A second person should control the door while you drill and mount hardware.

On fire-rated doors, confirm with the authority having jurisdiction before beginning. Drilling non-approved holes can void the door's fire rating.

Use a center punch on all metal door surfaces before drilling. Metal door faces deflect drill bits and produce misaligned holes.

Do not over-torque the mounting screws. Stripped screws in hollow metal doors are a common and difficult problem to correct after installation.

Keep the spring power dial or power adjustment at the factory default setting during initial installation. Set the final spring size only after the arm is attached and the door is cycling.

The Three Surface-Mounted Arm Configurations

Before touching the installation template, identify which arm configuration applies to your opening. The three configurations are not interchangeable, and using the wrong one changes which face of the door and frame the closer body mounts to, which side the arm shoe bracket goes on, and which template column to use.

Regular Arm

Closer body: Pull side of door

Arm extends to: Frame on pull side

Best for: Interior commercial doors, corridors, office doors

Profile: Arm projects outward from door face; highest visibility

Strength: Strongest closing force geometry

Parallel Arm

Closer body: Push side of door

Arm runs: Parallel to top of door when closed

Best for: Exterior commercial doors, high-security, vandal-prone openings

Profile: Low projection from door face; arm protected from vandalism

Strength: Slightly less mechanical advantage than regular arm

Top Jamb

Closer body: Frame head on push side

Arm connects to: Door top on pull side

Best for: Aluminum storefronts, narrow top-rail glass doors, frame-mount-only openings

Profile: Closer hidden at frame head; door face unmarked

Notes: May require soffit plate on aluminum extrusion frames

LCN 1000 Series surface mounted closers at SecurityParts.com available in regular arm, parallel arm, and top jamb configurations

Reading and Using the LCN Installation Template

The LCN installation template is a paper guide that ships inside the box with every new LCN closer. It is the most important tool in the installation process and the step that most field errors trace back to when skipped.

What the Template Shows

The template has separate columns for regular arm, parallel arm, and top jamb configurations. Each column shows the exact hole locations for both the closer body mounting holes and the arm shoe bracket holes relative to the door top edge and the door face. The template also shows the backset columns (the horizontal distance from the door edge to the latch bolt center) so the arm shoe is positioned correctly relative to the latch.

Step-by-Step Template Usage

Determine the correct template column Identify your arm configuration (regular, parallel, or top jamb). On the template, locate the column header for that configuration. If the door swings right (hinge on left), use the right-hand column. Left-swing doors use the left-hand column. Most LCN templates mark this clearly with an arrow and "Hinge Side" indicator.

Mark the centerline height on the door Most commercial installations place the closer centerline 1 inch from the door stop rabbet on the pull side. Measure from the top of the door down to this height and mark a horizontal line across the full door face with a pencil. This line is your alignment reference for the template.

Align the template fold line with the door top edge The template has a fold line or cut line that aligns with the top edge of the door. Fold the template along this line and position it so the fold sits at the door top edge and the template face lies flat against the door face. The centerline mark on the template should align with your pencil line.

Tape the template in place Use masking tape at all four corners. Verify the template has not shifted or bubbled before marking holes. A shifted template produces holes that are off by several millimeters, which changes the arm geometry at final installation.

Mark all hole centers with an awl or center punch On hollow metal doors, use a center punch and a single hammer tap to mark each hole center. This creates a small dimple that keeps the drill bit from walking across the metal surface. On wood doors, a sharp awl is sufficient. Mark every hole in the template before removing it.

Remove the template and drill all holes Use the correct bit size for the mounting screws supplied with the closer. For most LCN closers on hollow metal doors, this is a 7/32-inch bit. Drill straight through the door face only. Do not drill through the full door thickness unless instructed.

Save the template after installation. Tape the used template to the inside of the closer cover or keep it in the building maintenance file. When the closer needs to be replaced years later, the template eliminates the need to measure from scratch and confirms which configuration was installed.

How to Install a Door Closer on a Commercial Door: Regular Arm

Regular arm is the most common configuration for interior commercial doors. The closer body mounts on the pull side of the door face, and the arm extends from the body to a shoe bracket mounted on the frame.

LCN 4000 Series surface mounted closers including the 4040XP at SecurityParts.com

Mount the closer body to the door face Position the closer body over the drilled holes on the pull side of the door. Insert the mounting screws by hand first to confirm alignment, then drive them with a screwdriver. Do not use an impact driver. The screw seats are in lightweight hollow metal and strip easily under impact torque. Snug is correct. The body should sit flat against the door face with no rocking.

Confirm the spindle is in the correct position On the LCN 4040XP, the closer spindle (the shaft that the arm attaches to) should point toward the hinge side of the door. Verify this before attaching the arm. If the spindle points toward the latch side, the closer was mounted in the wrong orientation and will bind through the closing arc.

Close and fully seat the backcheck valve Turn the B valve fully clockwise before attaching the arm. This prevents the door from swinging open without resistance during the next step.

Attach the main arm to the spindle Slide the main arm onto the closer spindle. The arm should engage the splined or keyed spindle shaft securely. Insert the pinch bolt and tighten finger-tight only. Do not fully tighten yet. You may need to rotate the arm slightly during the next step to align the shoe bracket holes.

Mount the shoe bracket on the frame Hold the door at 90 degrees open (have your second person hold the door). Position the shoe bracket on the frame at the hole locations marked by the template. Insert and drive the shoe bracket screws fully. Frame mounting screws go through the door stop into the hollow metal frame. Use all provided screws.

Connect the forearm to the shoe bracket With the door held at 90 degrees, connect the forearm end of the arm assembly to the shoe bracket. Insert the connecting pin or bolt, and tighten. Now tighten the pinch bolt at the spindle connection. The arm should feel rigid with no lateral play.

Test the arm through the full arc before valve adjustment Slowly open the door to full extension and allow it to close freely. Watch the arm through the full arc. The arm should move smoothly with no binding, scraping, or sharp changes in resistance (other than the backcheck engaging at approximately 70 to 75 degrees). If the arm binds at any point, stop and check the geometry before proceeding to valve adjustment.

How to Install a Door Closer: Parallel Arm Configuration

Parallel arm places the closer body on the push side of the door. The arm runs parallel to the door top rail when the door is closed, which keeps the arm below the sight line and reduces exposure to deliberate damage.

Mount the closer body on the push side of the door Drill holes per the parallel arm column of the template. Mount the closer body on the push face of the door with the spindle pointing toward the hinge side. On the parallel arm configuration, the body position is farther from the latch edge than on a regular arm installation, per the template dimensions.

Mount the parallel arm bracket on the frame push side The parallel arm uses a two-piece bracket system: a main bracket on the frame head and an adjustable shoe. Mount the frame bracket at the hole locations from the parallel arm column of the template. The bracket mounts on the frame push side at the same elevation as the closer body.

Confirm backcheck valve is closed Turn the B valve fully clockwise before attaching the arm.

Attach the arm to the spindle The parallel arm assembly is slightly different from the regular arm: the main arm attaches to the spindle and runs back toward the hinge side when the door is closed. Insert the spindle connector and snug the pinch bolt.

Connect the forearm to the frame bracket With the door held at 90 degrees, connect the forearm to the frame bracket through the shoe. Adjust the shoe position along the frame bracket slot so the arm is under slight tension in the closed position without being overtightened. Tighten the shoe set screw and the pinch bolt.

Verify arm does not contact the door stop when closing Slowly close the door from 90 degrees and watch the arm clearance as the door reaches the frame. The arm must not contact the door stop or frame extrusion at any point in the arc. If it does, adjust the shoe position slightly toward the hinge side and retest.

How to Install a Door Closer: Top Jamb Configuration

Top jamb is required on aluminum storefront doors and any opening where there is no accessible door surface on the pull side for closer body mounting. The body mounts on the frame head, not the door.

When a Soffit Plate Is Required

On aluminum extrusion frames, the frame head surface is often a narrow extrusion that does not provide a flat mounting surface matching the closer body hole pattern. A soffit plate (also called a mounting plate) attaches to the frame head first, distributing the closer mounting load across the extrusion. Without it, the mounting screws pull through the thin aluminum extrusion under the repeated load of each door cycle.

Check whether your frame head is a standard hollow metal section (minimum 1/16-inch wall thickness) or an aluminum extrusion. Aluminum extrusions almost always require a soffit plate. Hollow metal sections typically do not.

Mount the soffit plate if required If the frame head is an aluminum extrusion, mount the soffit plate to the frame head first using self-tapping screws into the extrusion at the template-specified locations. The soffit plate creates the flat mounting surface the closer body needs.

Mount the closer body to the frame head (or soffit plate) Position the closer body on the frame head per the top jamb column of the template. The spindle should point downward toward the door on the pull side. Drive all mounting screws fully. On hollow metal frames, these screws go through the frame head into the frame interior.

Mount the arm shoe bracket on the door top rail The arm shoe for top jamb mounts on the door top rail on the pull side. Drill per the template hole locations. Drive all shoe bracket screws fully into the door top rail.

Close the backcheck valve before arm attachment Turn the B valve fully clockwise.

Attach the arm assembly from spindle to shoe With the door held at 90 degrees, connect the arm from the closer spindle down to the door top rail shoe bracket. Insert the connecting hardware and tighten. The arm should be under slight tension with the door in the 90-degree open position.

Test the arm for clearance through the full arc Close the door slowly and confirm the arm clears all frame geometry through the full closing arc. Top jamb arms can contact the frame head stop if the arm is too long or the shoe position is too far from the hinge side.

Arm Adjustment After Mounting

Checking Arm Geometry

Before adjusting any valves, check that the arm geometry is correct. Open the door to 90 degrees and look at the arm from above. At 90 degrees, the main arm and the forearm should form approximately a 90-degree angle between them. If the arm is near-straight (less than a 90-degree angle between the two arm segments) at 90 degrees open, the shoe is too close to the hinge side. If the angle is very acute (more than 90 degrees), the shoe is too far from the hinge side.

Incorrect arm geometry at 90 degrees produces inconsistent closing behavior and accelerated wear at the arm pivot. The template dimensions prevent this when followed correctly. If the geometry is off, reposition the shoe bracket before proceeding.

Arm Connection Tightening Sequence

After geometry is confirmed correct, fully tighten all arm connections in this sequence: the shoe bracket screws in the frame or door first, then the forearm-to-shoe connection, then the pinch bolt at the spindle. This sequence prevents a loose frame bracket from causing the arm to shift during pinch bolt tightening.

A loose arm shoe bracket is the most common cause of arm failure on commercial doors. The shoe bracket takes the full mechanical load of every closing cycle transmitted from the arm to the frame. Screws that were insufficiently torqued during installation work loose under repeated cycling and eventually allow the bracket to pivot, bending the forearm. Verify all bracket screws are tight before the installation is considered complete.

Spring Power Adjustment

Spring power determines how much force the closer exerts to close the door. Too little spring power and the door stalls before latching. Too much and the door exceeds the ADA 5-pound opening force limit.

LCN 4040XP External Spring Power Adjustment

The LCN 4040XP uses an external spring power adjustment dial, also called the LCN Green Dial, on the spring tube. This allows spring power adjustment without removing the closer from the door or disassembling the unit. The dial has numbered positions from 1 (minimum) through 6 (maximum). To increase spring power, turn the dial clockwise. To reduce it, turn counterclockwise. Start at position 3 or 4 for a standard 3-foot interior door and adjust from there based on performance testing.

Spring Sizes on Other LCN Models

On LCN 1000 Series and other models without an external dial, spring power is determined by which spring the unit ships with. These closers come in sizes 1 through 6, and changing the spring size requires replacing the spring assembly inside the closer body. For most commercial door applications, ordering the closer in the correct spring size from the outset is more practical than field-swapping springs.

Spring power and valve adjustment are different controls. The hydraulic valves (sweep, latch, backcheck) control how fast the spring closes the door. They do not change how hard you have to push to open it. Only spring size controls opening force. If a door requires more than 5 pounds to open after closer installation, the solution is a lighter spring, not a valve adjustment.

For specific parts for each LCN series including spring assemblies, arms, and mounting hardware, see the LCN 1000 Series door closer parts guide and the LCN 4000 Series door closer parts guide at SecurityParts.com.

Hydraulic Valve Adjustment After Installation

Once the arm is connected and the spring power is set, the three hydraulic valves need field adjustment to match the actual door conditions. All three valves are adjusted with a 3/32-inch hex key. Turn valves clockwise to restrict fluid flow and slow that phase of the closing arc. Turn counterclockwise to open flow and speed that phase up. Always make adjustments in 1/8-turn increments and test multiple cycles after each change.

Setting the Sweep Speed (S Valve)

The sweep valve controls the door from fully open down to approximately 10 to 15 degrees from the frame. Set the sweep speed first since it covers the longest portion of the closing arc. Target 5 to 7 seconds from 90 degrees to the point 3 inches from the frame on ADA-accessible doors. Time this with a stopwatch. If the door slams through the sweep arc, close the S valve clockwise. If it stalls before reaching the frame, open the S valve counterclockwise.

Setting the Latch Speed (L Valve)

The latch valve controls the final degrees from approximately 10 to 15 degrees to fully closed. Set it after the sweep is correct. The door should accelerate slightly through the latch zone and seat against the strike with a clean, firm click. If it stalls in the last few degrees or bounces back from the strike, open the L valve counterclockwise. If it slams into the frame, close it clockwise. The latch speed should always be slightly faster than the sweep speed.

Setting the Backcheck (B Valve)

Set the backcheck last. With the arm now connected and the door cycling correctly, slowly swing the door open past 75 degrees and feel for the resistance point. The backcheck should engage between 70 and 80 degrees and provide clear but not excessive resistance against the door being swung further open. If there is no resistance at all, close the B valve clockwise. If the backcheck engages too early (before 70 degrees) and makes the door feel stiff through the normal opening range, open it counterclockwise slightly.

For detailed valve adjustment guidance, seasonal calibration, and brand-specific instructions, see the complete commercial door closer adjustment guide at SecurityParts.com.

ADA Compliance After Installing a Door Closer on a Commercial Door

ADA compliance on door closers has two separate measurements that both must pass on accessible routes.

Opening Force: 5-Pound Maximum

Use a door pressure gauge at the leading edge of the door (the latch side). Push or pull perpendicular to the door face and read the peak force required to start the door moving. The limit is 5 pounds for interior non-fire-rated doors on accessible routes. If the reading exceeds 5 pounds, reduce spring power. Do not try to compensate with valve settings: valves do not control opening force.

Closing Speed: 5-Second Minimum

Using a stopwatch, time the door from 90 degrees open to the point 3 inches from the door stop. Per ANSI A117.1, the door must take a minimum of 5 seconds for this arc. If it closes faster, slow the sweep valve clockwise. A door that fails this test on an accessible route is an ADA liability regardless of how well everything else was done.

Spring size and wind load can make ADA compliance physically impossible with a conventional closer. On exterior doors subject to significant wind load, the spring must be strong enough to overcome the wind pressure and reliably latch the door. At the same time, the spring creates opening force that exceeds the 5-pound ADA limit. Where both requirements cannot be met simultaneously with a conventional closer, an automatic operator is the code-compliant solution.

Fire-Rated Door Closer Installation Requirements

Installing a door closer on a fire-rated commercial door involves requirements beyond standard closer installation. Non-compliance is discovered during NFPA 80 annual fire door inspections and can result in immediate deficiency citations.

The Closer Must Be Grade 1 and UL Listed

ANSI/BHMA A156.4 Grade 1 is the minimum standard for fire-rated door assemblies. The closer must also carry a UL listing for fire door use. A Grade 1 closer without a UL fire listing is not an acceptable specification on a fire-rated opening, even though the grade rating alone might suggest otherwise.

No Hold-Open Arms on Fire-Rated Doors

NFPA 80 Section 4.7.1 prohibits any device that holds a fire door open in a manner that is not connected to the fire alarm system. A mechanical hold-open arm or a slide track arm with a hold-open feature cannot be installed on a fire-rated door. Every fire door must close and latch automatically after each use. The only compliant hold-open solution for fire-rated doors is a fire-rated electromagnetic holder that releases when the fire alarm activates.

Closing Speed Must Latch Against Fire Door Resistance

Fire doors are typically heavier than non-rated interior doors and include intumescent seals that compress as the door closes. The closer must have enough spring power and latch speed to overcome this seal compression and produce positive latching on every cycle. After installation, test the door from a full open position by releasing it without assisting the close. The door must self-close and self-latch without manual assistance.

For fire door closer adjustment guidance specific to NFPA 80 closing speed requirements and spring size selection, see the fire door closer adjustment guide at SecurityParts.com.

Common Door Closer Installation Mistakes

Skipping the installation template The most common cause of incorrect arm geometry and premature arm failure. The template is not optional. It determines every hole position on both the door and the frame.

Not closing the backcheck valve before attaching the arm Opening a door with the backcheck fully open and no arm resistance can damage the closer body on the first cycle. Always seat the B valve clockwise before connecting the arm.

Mounting in the wrong arm configuration for the opening Installing a regular arm on a push-side application or a parallel arm on a pull-side opening reverses the mechanical advantage and produces incorrect geometry through the closing arc.

Under-torquing the arm shoe bracket screws The shoe bracket takes the full mechanical load of every closing cycle. Insufficiently tightened screws work loose under repeated cycling and allow the bracket to shift, bending the forearm arm and eventually damaging the closer spindle.

Using the wrong spring size for the door A spring too light for the door weight causes stall-before-latch. A spring too heavy produces opening force exceeding the ADA limit. Select the spring size by door width and weight, not by default to the closest spring on hand.

Adjusting valves on a door with incorrect arm geometry Valve adjustment cannot compensate for incorrect mounting. If the arm geometry is wrong, no combination of valve settings produces consistent closing behavior. Fix the geometry before touching the valves.

Installing a mechanical hold-open arm on a fire-rated door A direct NFPA 80 violation that will be cited on the next fire door inspection. Fire-rated doors must close and latch automatically on every cycle.

Skipping ADA verification after installation Installation is not complete until opening force and closing speed are measured with calibrated tools. Estimated compliance is not compliance.

Troubleshooting After Installation

Door stalls before latching
Open the L valve counterclockwise in 1/8-turn increments. If the door still stalls, increase spring power one size. Check that the strike and latch bolt are aligned before adjusting further.

Door slams into the frame
Close the L valve clockwise to slow the final arc. If slamming happens through the main arc, also close the S valve. Confirm spring size is not too large for the door.

Arm binds or feels stiff at a point in the arc
Stop immediately. A binding arm almost always indicates incorrect geometry. Check that the shoe bracket is at the correct template position. A binding arm puts destructive lateral load on the closer spindle.

Opening force exceeds 5 pounds for ADA
Reduce spring power. Valve settings do not change opening force. On LCN 4040XP, reduce the spring power dial setting. On other models, replace with a smaller spring.

Door closes too slowly for fire door latching
Open the L valve counterclockwise. Increase spring size if the door still cannot overcome seal compression. Verify the arm geometry is correct and the arm is not binding.

Closer body rocks or is not flush against door
Holes may be misaligned due to template not being held flat. Remove the closer and verify hole positions against the template. Re-drill if necessary using a longer drill guide.

Arm shoe bracket loosens after a few days
All frame screws were not driven fully. Remove the arm, re-drive all shoe bracket screws to full torque, and reattach the arm. Use thread-locking compound on the bracket screws if the holes are in a hollow section with minimal thread engagement.

Door does not pull completely closed in cold weather
Cold hydraulic fluid thickens and slows the closing arc. Seasonal valve adjustment is normal. Open the S and L valves slightly counterclockwise. If the closer uses standard (non-all-weather) hydraulic fluid, consider replacing the unit with an all-weather fluid model for exterior or temperature-exposed applications.

For broader door hardware troubleshooting beyond the closer itself, see the commercial door hardware troubleshooting guide at SecurityParts.com.

Maintenance After Installing a Door Closer on a Commercial Door

A correctly installed and adjusted commercial door closer requires minimal maintenance but does need periodic attention to stay in compliance and perform consistently.

Inspect the arm connections and shoe bracket screws at every scheduled maintenance visit. Tighten any screws that show movement. On high-traffic doors, this should happen quarterly.

Check closing speed with a stopwatch at the start of heating season and cooling season. Seasonal temperature changes affect hydraulic fluid viscosity and will shift valve performance. A few minutes of valve adjustment twice a year keeps the closer in spec.

Inspect the arm pivot pins for wear. A worn or loose pivot pin produces arm rattle and changes the arm geometry subtly over time. Replace worn pivot hardware before the geometry shift damages the closer spindle.

On exterior and vestibule closers, verify the cover plate is fully seated and undamaged. A missing or cracked cover exposes the valve ports to debris and water on exterior applications.

Confirm ADA compliance measurements annually during fire door inspections and whenever the closer has been adjusted or the door has been re-hung.

For a complete maintenance schedule with monthly, quarterly, and annual task breakdowns, see the commercial door hardware maintenance checklist at SecurityParts.com. For door closer component identification, see the door closer parts diagram.

Why Choose SecurityParts.com for LCN Door Closer Parts

SecurityParts.com has supplied commercial door hardware parts since 2001. The LCN door closer catalog at SecurityParts.com covers the complete range including the 1000 Series, 4000 Series (4040XP), 3030/3130 overhead concealed, 2010/5010, 2210 high-security, and Sentronic electrified closers. Every model page includes an interactive parts diagram so you can identify the exact arm, shoe, bracket, spring, or cover plate needed before placing an order.

Browse the LCN 1000 Series surface mounted closer parts, the LCN 4000 Series surface mounted closer parts, the LCN 1000 Series parts guide, and the LCN 4000 Series parts guide. Browse the complete LCN door closer parts catalog and all SecurityParts.com commercial door hardware parts. Call 845-935-0301 or visit the SecurityParts.com contact page for pre-installation parts identification and same-day shipping support.

This guide on how to install door closer on commercial door is maintained by the commercial door hardware team at SecurityParts.com. For LCN door closer parts identification and same-day shipping support, call 845-935-0301 or browse the LCN door closer parts catalog.

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Access Control Integration with Commercial Door Hardware: Electric Strikes, EL, QEL and Fail-Safe vs Fail-Secure Guide Thursday, July 23, 2026

Four electrified hardware types integrate with access control systems: electric strikes (frame-side device releasing the latch), electric latch retraction exit devices (EL/QEL, retracting the latch inside the door), electrified mortise or cylindrical locks (electrified lever control), and electromagnetic locks (power-to-lock). Key rules: electric strikes on fire-rated doors must be fail-secure. Stairwell reentry requires fail-safe electrified hardware, but fail-safe electric strikes cannot be used on fire doors. EL uses a solenoid; QEL uses a quieter motor and should be specified for high-cycle and noise-sensitive applications. Use 12V DC for runs under 100 feet; 24V DC for longer runs. Never install an electric strike and EL device on the same opening. Request to exit (RX) switches are required on access-controlled egress doors to distinguish legitimate exits from forced entry.

Every access control project involves at least one decision about electrified door hardware, and that decision has code, fire safety, and security consequences that a wrong choice cannot easily fix after installation. The fail-safe vs fail-secure choice determines whether a door unlocks or stays locked during a power failure. The stairwell reentry rule eliminates fail-safe electric strikes from fire-rated stair doors entirely. The EL vs QEL choice affects daily noise levels in noise-sensitive facilities for years. Getting these right at specification time prevents costly retrofits and code citations.

For OEM electrified hardware parts at SecurityParts.com, browse Von Duprin 5100, 6100, 6200, and 6300 Series electric strike parts, Von Duprin EL and QEL exit device parts, Schlage electrified cylindrical lock parts, and Schlage electrified mortise lock parts.

Fail-Secure Mandatory on electric strikes installed on fire-rated doors for positive latching compliance

No FS Strike Fail-safe electric strikes cannot be used for stairwell reentry: fire doors must be positively latched

QEL Motor-driven: quieter than solenoid EL, with diagnostics, calibration, and longer cycle life

100 ft Approximate wire run threshold for choosing 12V vs 24V DC: use 24V for runs longer than 100 feet

The Four Electrified Hardware Types and When Each Is Used

Frame-Side Electric Strike

How it works

An electric strike replaces the fixed strike plate in the door frame. A moving keeper inside the strike body either holds the latch bolt secure (locked) or pivots out of the way to allow the latch bolt to pass through (unlocked). Electricity controls the keeper position. The lock on the door side remains fully mechanical: the person inside can always retract the latch by turning the lever or pushing the exit device push bar, regardless of whether the strike is powered.

When to specify

Electric strikes are the correct choice when adding access control to a door that already has a cylindrical or mortise lock, when frame cutting is acceptable, or when the opening does not have an exit device and frame-side control is sufficient. They are the most economical electrified hardware option. Von Duprin's 5100 Series covers standard commercial cylindrical and mortise applications. The 6100 is heavy-duty. The 6200 provides high-security fail-secure performance. The 6300 covers the widest lock compatibility range.

When NOT to specify

Do not install an electric strike on the same opening as an EL or QEL device: this creates a redundant and failure-prone system. Do not specify a fail-safe electric strike on a fire-rated door: fire doors must be positively latched, which requires fail-secure strikes. Do not use an electric strike for stairwell reentry on a fire-rated door for the same reason.

Browse Von Duprin 5100, 6100, 6200, and 6300 Series electric strike parts at Security Parts.

Door-Side Electric Latch Retraction (EL / QEL)

How EL works

Electric Latch Retraction (EL) is a function available on Von Duprin exit devices (98/99, 22, 33A/35A, and related series) where a solenoid inside the device body retracts the latch bolt when powered. When the access control system signals the door to open, the solenoid activates, pulling the latch to the retracted position. The door then opens freely as push-pull without anyone pressing the push bar. The push bar always provides mechanical egress regardless of power state.

How QEL is different

QEL (Quiet Electric Latch Retraction) replaces the solenoid with a motor-driven mechanism. The motor actuates much more quietly than a solenoid. QEL also provides features not available on EL: troubleshooting diagnostics, automatic calibration, a retry mode that automatically reattempts retraction if the first attempt fails, and vandal resistance detection that signals the access control panel if the push bar is subject to sustained impact.

When to specify QEL over EL

QEL is the correct specification for hospitals, healthcare corridors, libraries, museums, classrooms, theaters, and any noise-sensitive environment. Also specify QEL on any high-cycle door (500 or more cycles per day) because the motor mechanism has longer cycle life than the solenoid-based EL under continuous high-cycle conditions.

The EL high inrush current fact that causes the most field wiring problems: EL devices (solenoid-based) have a high inrush current at the moment of activation, significantly higher than their steady-state holding current. A power supply sized to the steady-state current specification alone will not reliably support the inrush current on EL activation, causing solenoid activation failures that appear intermittent. Always size the power supply and wire gauge to handle the inrush current of the EL devices it serves, not just the holding current. Von Duprin provides inrush current specifications in the PS900 series power supply documentation. QEL devices have lower and more predictable current draw due to the motor mechanism, making power supply sizing more straightforward.

Browse Von Duprin EL and QEL electrified exit device parts at Security Parts.

Door-Side Electrified Mortise or Cylindrical Lock

How it works

An electrified mortise or cylindrical lock is a standard mechanical lock that has been modified with an electrical component that controls whether the outside lever can be operated. In the electrically locked (EL) configuration, power must be applied to unlock the outside lever. In the electrically unlocked (EU) configuration, power must be applied to lock the outside lever. The inside lever always operates freely, providing egress regardless of power state.

When to specify

Electrified mortise and cylindrical locks are the correct choice when access control is needed at a standard corridor or entry door without an exit device, when the latch mechanism itself should be controlled rather than the strike, when fail-safe operation is required on a non-fire-rated door (fail-safe electromechanical locks are used for stairwell reentry), or when an electrified mortise provides a cleaner aesthetic than a strike-based solution.

Key limitation

Electrified mortise and cylindrical locks cannot be used with automatic operators because the latch is not retracted until someone turns the lever. If an automatic operator opens the door before the lever is turned, the latch will interfere with the opening. For automatic operator applications, an electric strike or EL/QEL device is required.

Browse Schlage L Series electrified mortise lock parts and Schlage ND Series electrified cylindrical lock parts at Security Parts.

Frame-Side Electromagnetic Lock

How it works

An electromagnetic lock (maglock) is an electromagnet mounted on the door frame with a steel armature on the door. When power is applied, the magnet bonds to the armature with substantial holding force. When power is cut, the bond releases and the door opens. Electromagnetic locks are power-to-lock devices: they are always fail-safe. There is no mechanical locking component: the bond is purely electromagnetic.

Critical limitations

Electromagnetic locks are only fail-safe. There is no fail-secure electromagnetic lock. This makes them unsuitable for fire-rated doors (which require positive latching, not electromagnetic bonding) and for most secured perimeter applications where the door must remain locked during a power failure. Maglocks are appropriate for controlled access doors in non-fire-rated applications where the fail-safe characteristic is acceptable or required, such as interior access control doors or elevator lobbies.

Fail-Safe vs Fail-Secure: The Decision Framework

This is the decision that determines whether a door creates a security risk or a safety hazard when power fails. There is no universal correct choice: the selection depends on the door's location, fire rating, life safety code requirements, and occupancy.

Fail-Safe (Unlocks When Power Is Cut)

Use when: people must be able to exit or re-enter during a fire alarm or power failure

Required for: stairwell reentry doors, healthcare controlled egress where the code requires unlocking on alarm, elevator lobby exit access doors

Hardware types: fail-safe electromechanical locks, fail-safe electrified lever trim for fire exit hardware, electromagnetic locks

Fire door rule: fail-safe electric strikes CANNOT be used on fire doors: fail-safe strikes do not maintain positive latching

Security risk: door is unlocked during any power interruption, including intentional power cuts during a forced entry attempt

Fail-Secure (Stays Locked When Power Is Cut)

Use when: the door must remain locked to prevent unauthorized access during a power failure

Required for: electric strikes on fire-rated doors (mandatory to maintain positive latching), perimeter security doors, data rooms, cash vaults

Hardware types: fail-secure electric strikes, EL/QEL exit devices (always fail-secure: latch projects when power is removed), fail-secure electromechanical locks

Fire door rule: electric strikes on fire-rated doors MUST be fail-secure for positive latching compliance with NFPA 80

Free egress: all fail-secure hardware still provides free egress from inside the door (lever turns or push bar actuates) regardless of power state

The Stairwell Reentry Rule: The Most Common Fail-Safe vs Fail-Secure Specification Error

Most building codes (IBC and NFPA 101) require stairwell doors to allow reentry from the stair back into the building during a fire. This means the stair side lever must unlock during a fire alarm. This requires fail-safe hardware on the stair side. However, stairwell doors are fire-rated doors, which must be positively latched at all times.

This creates an apparent conflict: the door must be fail-safe for reentry (unlocking on alarm) and fail-secure for the fire rating (positively latched during a fire). The resolution: fail-safe electrified lever trim for fire exit hardware maintains the positive latch (the EL mechanism keeps the latch bolt projected) while providing fail-safe outside lever control (the lever unlocks when power is cut). A fail-safe electric strike alone cannot satisfy both requirements because a fail-safe electric strike does not maintain positive latching when power is cut.

The specific code language that disqualifies fail-safe electric strikes from stairwell reentry: Codes require stairwell reentry doors to be equipped with fail-safe electrified locks or fail-safe electrified lever trim for fire exit hardware. A fail-safe electric strike is not equivalent to either of these. On a fire door, the electric strike's spring-loaded keeper provides insufficient holding force to maintain positive latching under fire pressure conditions when power is cut. Installing a fail-safe electric strike for stairwell reentry compliance and assuming it satisfies both the reentry requirement and the fire door positive latching requirement is a specification error that creates both a life safety code violation and a fire separation failure risk.

Von Duprin Electric Strike Series at Security Parts

Series	Performance Level	Key Feature	Voltage	Primary Application
5100 Series	Medium duty	Dual voltage, selectable fail mode	12V / 24V DC	Standard commercial cylindrical and mortise lock applications
6100 Series	Heavy duty Grade 1	Broader lock compatibility, dual voltage	12V / 24V DC	Heavy commercial, institutional cylindrical and mortise
6200 Series	High security fail-secure	Maintained locked position during power failure; high holding force	12V / 24V DC	High-security perimeter doors requiring fail-secure integrity
6300 Series	Wide compatibility	Widest lock compatibility across cylindrical, mortise, and panic hardware	12V / 24V DC	Mixed hardware environments; broadest application range

Parts across all four Von Duprin electric strike series include solenoid assemblies, strike plates, cover kits, and mounting hardware. Electric strike components are not cross-compatible between series: a solenoid from the 6200 series will not fit a 6100 unit. Always order replacement parts by confirming the exact series before ordering. Browse Von Duprin electric strike parts by series at Security Parts.

Von Duprin Exit Device Electrification Options

EL: Electric Latch Retraction

Order prefix: EL (e.g., EL99L)

Solenoid retracts latch for remote access control. Audible solenoid click during activation. High inrush current at activation. Always fail-secure: latch projects when power is removed. Available on rim, SVR, CVR, and mortise configurations.

QEL: Quiet Electric Latch Retraction

Order prefix: QEL (e.g., QEL99L)

Motor-driven retraction: significantly quieter than EL. Computer features: diagnostics, auto calibration, retry mode, vandal detection. Lower and more consistent current draw. Specify for noise-sensitive applications and high-cycle (500+ cycles/day) openings.

RX: Request to Exit Switch

Order suffix: RX

Dry contact switch signals access control panel when push bar is pressed. Distinguishes legitimate egress from forced entry for alarm management. Required on access-controlled egress doors. Available on 98/99, 22, 33A/35A, and related series.

LX: Latch Monitor Switch

Order suffix: LX

Monitors whether latch bolt is in the projected (latched) or retracted position. Signals access control panel of latch state. Used for door status monitoring in security-sensitive applications. Combined with door position switch for complete door status monitoring.

SS: Signal Switch

Order suffix: SS

Dry contact that closes when the push bar or touch pad is depressed. Simpler than RX: monitors bar depression rather than latch retraction. Used when access control panel needs bar actuation signal without full RX integration.

DPS: Door Position Switch

Order suffix: DPS

Monitors whether the door is open or closed, independent of the latch state. Used with RX and LX for complete access control monitoring. Enables forced door alarm when door opens without an authorized credential or push bar event.

12V vs 24V DC: Voltage Selection for Electric Door Hardware

Most Von Duprin electric strikes and electrified exit devices operate on either 12V or 24V DC, with many models field-selectable between the two. The selection is based primarily on wire run length from the power supply to the device.

Why Voltage Drop Matters

Wire resistance causes a voltage drop proportional to the wire length and the current drawn by the device. A solenoid that receives insufficient voltage activates weakly, actuates intermittently, or does not actuate at all. This produces field failures that appear random and are difficult to diagnose because the device tests fine when connected directly to the power supply (short run) but fails in the installed long-run condition.

At 24V, the same absolute voltage drop across the wire resistance removes a smaller percentage of the supply voltage at the device than at 12V. For example: a 1-volt drop in a 100-foot 16-gauge wire run takes 8.3 percent of a 12V supply but only 4.2 percent of a 24V supply. The device at the end of the 24V run receives a higher percentage of its rated voltage.

Selection Guidelines

Use 12V DC for wire runs shorter than approximately 100 feet where voltage drop is manageable, and for devices that do not offer a 24V option.

Use 24V DC for wire runs over 100 feet. Calculate the actual voltage drop based on wire gauge and run length to confirm the device receives sufficient voltage at the rated gauge before finalizing the installation.

The correct voltage drop calculation approach for electric strike runs: Voltage drop (in volts) equals 2 times the run length in feet times the current draw in amperes, divided by the wire gauge conductance value. Use the inrush current (not steady-state) for EL solenoid devices. Confirm the resulting device voltage is at least 85 percent of the rated operating voltage for reliable actuation. If the device receives less than 85 percent of rated voltage on the highest current draw scenario, increase wire gauge or switch to 24V supply.

Von Duprin Power Supplies for Electrified Door Hardware

Von Duprin PS900 series power supplies are the correct power supply for Von Duprin electric strike and electrified exit device applications. The PS900 series is sized to handle the inrush current requirements of EL solenoid devices in addition to their steady-state holding current. Using a generic 12V or 24V power supply not designed for solenoid inrush current can cause intermittent actuation failures even when the voltage output appears correct.

The PS900 series is available in 12V and 24V DC output versions and in multiple current capacities to serve different numbers of devices from a single supply. For multi-door access control systems, the power supply current capacity must accommodate the simultaneous inrush current of all devices that could activate at the same time, not just the steady-state current of all devices. Browse the Von Duprin power supply catalog at SecurityParts.com alongside the Von Duprin electric strike parts and EL and QEL exit device parts.

Request to Exit (RX) Switch: Why It Is Required on Access-Controlled Doors

A request to exit (RX) switch is built into an exit device and generates a signal to the access control panel whenever the push bar or touch pad is actuated. The access control panel uses this signal to distinguish between two events that otherwise look identical from a door position perspective: a door opening after an authorized credential has been presented from outside (normal entry), and a door being pushed open from inside (legitimate egress).

Without an RX signal, the access control system cannot tell whether a door opening represents an authorized entry or a legitimate exit. This forces the system to either generate false alarms on every legitimate exit or to disable door-forced alarms entirely. Neither outcome is acceptable in a security system.

The RX signal flow: occupant presses push bar, RX switch closes, signal sent to access control panel, panel records an egress event and suppresses a door-forced alarm for the shunt time (typically 5 to 10 seconds to allow the door to close). If the door opens without either an RX signal (egress) or a credential event (entry), the panel generates a door-forced alarm.

Browse Von Duprin exit device parts including RX, LX, DPS, and SS switch options at SecurityParts.com. For the complete Allegion electrified hardware parts catalog, browse all products at SecurityParts.com. Pre-order support at 845-935-0301 or the contact page.

Why Choose SecurityParts.com for Electrified Door Hardware Parts

Stairwell reentry code detail, EL inrush current warning, fail-safe fire door prohibition, QEL vs EL cycle life guidance, and same-day OEM shipping.

Stairwell Reentry Code Detail

We document why fail-safe electric strikes cannot satisfy stairwell reentry requirements on fire doors. This is the most common fail-safe vs fail-secure specification error and is not documented in any competitor content at the parts ordering level.

EL Inrush Current Warning

We document the EL solenoid high inrush current issue and why power supply sizing to steady-state current alone causes intermittent field failures. QEL's motor mechanism eliminates this problem with more consistent current draw.

RX Switch Function Explained

We document why RX switches are required for alarm shunting and how the RX signal distinguishes legitimate egress from forced entry. This prevents both false alarms and disabled door-forced alarms in access control systems.

Same-Day OEM Shipping

Von Duprin EL, QEL, electric strike, and access control switch parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for electrified hardware compatibility support.

What Makes Security Parts Different for Access Control Hardware Parts

We document the stairwell reentry fail-safe electric strike prohibition in detail: fail-safe electric strikes cannot provide positive latching on fire-rated stair doors, making them non-compliant for reentry on fire doors regardless of the access control requirement. This code nuance is absent from all competitor parts supplier content.
We document the EL solenoid inrush current issue and the QEL motor mechanism advantage. Power supply failures on EL installations from undersized supplies are the most common electrified door hardware field failure and are not documented in any competitor content.
We document the electrified lock and automatic operator incompatibility: electrified mortise and cylindrical locks cannot be used with automatic operators because the latch does not retract until the lever is turned. This requires using electric strikes or EL/QEL instead, which is never explained in standard access control hardware content.
We document the RX switch alarm shunt function and why door-forced alarms without RX produce either continuous false alarms or disabled security monitoring. Both outcomes are security failures that the RX switch specification prevents.
We carry Von Duprin electric strike parts, EL and QEL exit device parts, electrified mortise lock parts, and electrified cylindrical lock parts for complete access control integration in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Frequently Asked Questions About Access Control and Commercial Door Hardware

What is the difference between fail-safe and fail-secure electrified door hardware?

Fail-safe unlocks when power is removed. Fail-secure stays locked when power is removed. Both always provide free egress from the inside. Key rules: electric strikes on fire-rated doors must be fail-secure for positive latching compliance. Stairwell reentry requires fail-safe electrified hardware (electromechanical locks or fail-safe electrified trim for fire exit hardware) but not fail-safe electric strikes, which cannot maintain positive latching on fire doors. Electromagnetic locks are a fail-safe only.

Why can't a fail-safe electric strike be used for stairwell reentry on fire-rated doors?

Fire-rated doors require positive latching during fire events. A fail-safe electric strike releases its keeper when power is cut. Under fire pressure conditions, the spring-loaded keeper alone provides insufficient holding force, allowing the latch bolt to be pushed through and the door to open, compromising fire separation. Stairwell reentry on fire-rated doors requires fail-safe electrified lever trim for fire exit hardware or fail-safe electromechanical locks, which maintain positive latching while unlocking the outside lever on fire alarm.

What is the difference between Von Duprin EL and QEL electric latch retraction?

EL uses a solenoid: audible click during activation, high inrush current at activation, standard cycle life. QEL uses a motor-driven mechanism: significantly quieter operation, lower and more consistent current draw, longer cycle life, plus computerized features including troubleshooting diagnostics, automatic calibration, retry mode, and vandal resistance detection. Specify QEL for hospitals, libraries, healthcare, noise-sensitive environments, and any door cycling more than 500 times per day.

When should an electric strike be used instead of electric latch retraction on an exit device?

Use an electric strike when adding access control to a cylindrical or mortise lock (not an exit device), when budget is the primary constraint, or when frame cutting is acceptable. Use EL or QEL when the opening has an exit device and frame cutting must be avoided (especially on fire-rated doors where frame cuts can affect assembly listings), when fail-secure performance with the lowest frame damage risk is needed, or when the combined access control and business-hours push-pull function of EL/QEL is needed. Never combine an electric strike and EL device on the same opening.

Should I use 12V or 24V DC for electric strikes and electrified door hardware?

Use 12V DC for wire runs under approximately 100 feet. Use 24V DC for runs over 100 feet to compensate for voltage drop across wire resistance. At 24V, the same absolute voltage drop represents a smaller percentage of supply voltage, ensuring the device receives sufficient voltage for reliable actuation. For EL solenoid devices, calculate voltage drop using inrush current (not steady-state current) to confirm adequate supply voltage at the device under worst-case conditions.

What is a request to exit (RX) switch and why is it required on access-controlled doors?

An RX switch signals the access control panel when the exit device push bar is pressed. The panel uses this signal to distinguish legitimate egress (bar pressed from inside) from forced entry (door opened without credential or bar event). Without RX, the system either generates continuous false alarms on every legitimate exit or disables door-forced alarms entirely. The RX signal shunts the door-forced alarm for a set time (typically 5 to 10 seconds) after bar depression, allowing the door to open and close without generating a false alarm while maintaining security monitoring.

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Schlage ALX Series Guide: Function Codes, Door Prep Template, In-Field Function Change, and OEM Parts Thursday, July 23, 2026

The Schlage ALX Series is a commercial cylindrical lock line that combines ANSI A156.2 Grade 2 performance with a practical in-field function change capability that saves significant labor on renovation projects. Whether you are specifying the Schlage ALX Series for a new office build-out, installing a unit on an existing door using the Schlage ALX template, or changing the lock function to suit a new tenant, this guide covers every function code, the exact door preparation dimensions, the in-field function change procedure, and how to identify and order OEM replacement parts at SecurityParts.com.

SecurityParts.com stocks Schlage ALX Series parts and components. Browse the Schlage ALX Series parts and diagrams, the complete Schlage hardware parts catalog, or the commercial cylindrical lock parts catalog. For parts identification support, call 845-935-0301 or visit the SecurityParts.com contact page.

Schlage ALX Series cylindrical lock Grade 2 commercial with in-field function change capability

What Is the Schlage ALX Series?

The Schlage ALX Series is a commercial-grade cylindrical lock designed for light-to-medium traffic openings in office, healthcare, education, and multi-family residential applications. It is rated ANSI A156.2 Grade 2, which means it meets the standard for commercial applications where Grade 1 heavy-duty performance is not required. The ALX Series replaced the Schlage AL Series as the current-generation commercial cylindrical product and carries the same fundamental door preparation dimensions, making it a direct field replacement on doors previously fitted with AL Series hardware.

The defining feature of the Schlage ALX Series is its in-field function change (IFFC) capability. The function of the lock, which determines how each side operates in relation to the other, can be changed after the lock is already mounted on the door without removing the lock body, replacing trim, or re-keying. This single capability makes the ALX Series significantly more practical than fixed-function cylindrical locks on renovation projects where tenant configurations change frequently.

Schlage ALX Series Grade and Standards

The Schlage ALX Series is certified to ANSI A156.2 Grade 2 for cylindrical and bored locks. Grade 2 requires a minimum of 250,000 operating cycles, a 450-pound static load resistance on the bolt, and 250 pounds of force resistance on the lock body. These ratings make the ALX Series appropriate for interior openings in commercial and institutional buildings where the door is used frequently but does not face the abuse-level forces of a Grade 1 application.

The ALX Series is also UL listed for use on fire-rated assemblies in specific configurations, making it suitable for interior fire-rated corridor doors in office and healthcare settings. Always confirm the UL listing of the specific function code before specifying on a fire-rated opening.

Schlage ALX Series Function Codes: Every Model Explained

Every Schlage ALX Series lock is designated by a function code that determines how the outside lever and inside lever operate independently. Understanding the function codes is the first step in both specifying the correct lock and using the in-field function change feature to move between functions after installation.

Schlage ALX Series function codes guide each lock's operation from passage to storeroom

ALX10S
Passage LatchLever always free from both sides. Latch retracts by operating either lever. No locking function. Used for interior doors that must always remain accessible such as waiting rooms and open office areas.

ALX40
PrivacyInside push button locks the outside lever. Outside can be unlocked with an emergency release tool (small flat tool through the outside rose pinhole). Used for single-occupancy restrooms and private offices.

ALX44S
Entry with Turn ButtonOutside lever is locked or unlocked by key from outside or turn button from inside. Inside lever is always free. Used for building entry doors and suite entry where key control from outside is needed.

ALX50
EntranceOutside lever locked or unlocked by key from outside. Inside lever always free. Key holdback from outside not available. Used on entry doors requiring key control without key holdback capability.

ALX53
OfficeOutside lever locked or unlocked by key from outside with key holdback. Inside lever always free. Key holdback keeps the lock unlocked for business hours without a key in the outside lever. Widely used on office suite doors.

ALX70
ClassroomOutside lever locked or unlocked by key from outside only. Inside lever always free. Cannot be held in the unlocked position from outside. Used on classroom and institutional corridor doors where outside access is key-only at all times.

ALX80
StoreroomOutside lever always locked. Entry by key from outside only. Inside lever always free for egress. Used on storage rooms, server rooms, and utility closets requiring constant key control from the outside.

ALX170
Single DummyTrim only, no latch or lock mechanism. One lever on one side of a door for appearance or pull function only. Used on double doors where one leaf is inactive and only a pull handle is needed.

ALX172
Double DummyTrim only on both sides, no latch or lock mechanism. Used where a lever appearance is needed on both sides of an inactive door leaf or a door that is not a functioning entry point.

Schlage ALX Template: Door Preparation Dimensions

The Schlage ALX template is the paper drilling guide that ships with every new Schlage ALX Series lock. It sets out the precise hole positions for the cross bore, latch bore, and edge bore so the lock body, latch, and trim align correctly after installation. Using the Schlage ALX template before drilling is the only reliable way to ensure all three holes are correctly positioned relative to each other and to the door edge.

Standard Schlage ALX Template Dimensions

Cross Bore (Face Bore)

2-1/8"

Hole diameter through the door face where the lock body passes through

Standard Backset

2-3/4"

Distance from door edge to cross bore centerline. Also available in 2-3/8" backset.

Latch Bore (Edge Bore)

Hole diameter on the door edge for the latch bolt assembly

Latch Faceplate

1" x 2-1/4"

Standard flat corner faceplate. Mortise pocket cut flush with door edge.

Door Thickness

1-3/8" to 1-3/4"

Standard range. Through-bolts adjust to door thickness within range.

Strike Plate

ANSI T-Strike

Standard ANSI T-strike with 1-1/4" x 4-7/8" faceplate and strike box

How to Use the Schlage ALX Template

Measure and mark the lock centerline height Standard commercial door lock centerline is 38 inches from the finished floor. Mark this height on the door edge with a pencil line across the full door thickness.

Position the Schlage ALX template on the door face Fold the template along the door edge fold line. Align the backset marker on the template with the desired backset (2-3/4 inch for standard or 2-3/8 inch for narrow stile). Align the horizontal centerline of the template with the lock height mark on the door edge. Tape the template in place.

Mark the cross bore center Use an awl or sharp pencil to mark the cross bore center through the template. This is the center of the 2-1/8 inch hole that passes through the door face.

Mark the latch bore center on the door edge The template includes a fold line for the door edge. With the template folded around the edge, mark the latch bore center on the door edge at the intersection of the lock height line and the edge template centerline.

Drill the cross bore first Use a 2-1/8 inch hole saw. Drill from one face until the pilot bit just breaks through the opposite face, then complete the hole from the opposite face to prevent tear-out on the door face veneer.

Drill the latch bore on the door edge Use a 1 inch spade bit or forstner bit. Drill perpendicular to the door edge at the marked center. Depth should be sufficient for the full latch assembly length.

Chisel the latch faceplate mortise Score the faceplate outline on the door edge using the latch assembly as a template. Chisel the mortise to the depth of the faceplate thickness so the faceplate sits flush with the door edge surface.

Install and test before finishing Insert the latch assembly, mount the lock body, and test operation before applying any door finish or painting. Confirm the latch extends and retracts freely and the door closes and latches cleanly against the strike.

Always drill the cross bore before the latch bore. Drilling the latch bore first removes wood from the door edge that the cross bore drill bit's pilot would otherwise travel through cleanly. Drilling in the correct sequence prevents the pilot bit from deflecting into the latch bore cavity and producing a misaligned cross bore.

Replacing an existing lock: verify backset before ordering. If you are replacing an existing cylindrical lock with a Schlage ALX Series unit, measure the backset of the existing installation before ordering. A 2-3/4 inch backset ALX unit cannot be used on a door prepped for a 2-3/8 inch backset without re-drilling the latch bore position, which requires repatching the door edge. Confirm the backset by measuring from the door edge to the center of the existing cross bore before placing the order.

Schlage ALX Series In-Field Function Change: Step-by-Step Guide

The Schlage ALX Series in-field function change (IFFC) is the feature that makes the ALX Series a practical choice for buildings with changing tenant configurations. Instead of removing the lock, sourcing a different function unit, and reinstalling, the facility manager changes the function at the door in minutes using only the Schlage IFFC change tool.

What You Need for the In-Field Function Change

The Schlage ALX in-field function change requires only the Schlage IFFC change tool (Schlage part C415-782). No other tools are required. The lock stays on the door throughout the procedure. The function change does not affect the keying of the lock, so re-keying is not required after a function change.

In-Field Function Change Procedure

Open the door and hold it open The function change must be performed with the door open so the latch bolt is not engaged in the strike. The bolt must be in the retracted position for the mechanism to cycle freely.

Locate the IFFC change port on the inside rose The change port is a small circular opening on the inside rose or inside escutcheon. On ALX Series locks it is typically at the 6 o'clock position on the rose when the lever is in the neutral position. A small function indicator window next to the port displays the current function code.

Insert the IFFC tool into the change port Insert the tip of the C415-782 IFFC tool into the change port. Apply light inward pressure to engage the tool with the change mechanism inside.

Turn the inside lever while pressing the tool Simultaneously press the IFFC tool inward and turn the inside lever in the direction indicated by the function diagram on the template that shipped with the lock. One lever operation advances the mechanism one function position.

Check the function indicator window Release the tool and lever. Read the function code displayed in the indicator window. Repeat steps 3 and 4 until the desired function code appears.

Test both sides before closing the door Confirm the new function operates correctly from both sides of the open door before closing. For storeroom (ALX80), confirm the outside lever does not operate without a key. For passage (ALX10S), confirm both levers operate freely. Confirm the latch retracts and returns correctly.

Close and test the door in the frame Close the door and confirm the latch engages the strike cleanly. Test all functions again from both sides of the closed door to confirm the function change is complete and operating as specified.

The function change sequence is fixed and cycles in one direction only. The Schlage ALX IFFC mechanism cycles through functions in a set order. If you overshoot the desired function, continue cycling through the remaining functions until you return to the one you need. The sequence is: passage, privacy, entrance, office, classroom, storeroom, and back to passage. You cannot reverse direction.

Schlage ALX Series vs ND Series: Which to Specify

Schlage ND Series Grade 1 cylindrical lock compared to the ALX Series Grade 2 for commercial specification decisions

Schlage ALX Series

ANSI A156.2 Grade 2

Traffic: Light to medium commercial

Cycle life: 250,000 cycles minimum

Applications: Office interiors, healthcare exam rooms, multi-family units, light commercial

IFFC: Yes in-field function change supported

Door prep: 2-1/8" cross bore, 2-3/4" standard backset, 1" latch bore

Key systems: Everest and C keyway, SFIC compatible

Trim: Wide lever and rose selection

Schlage ND Series

ANSI A156.2 Grade 1

Traffic: Heavy commercial and institutional

Cycle life: 1,000,000+ cycles on Grade 1 models

Applications: Main entry doors, high-traffic corridors, hospitals, universities, correctional

IFFC: Yes in-field function change supported

Door prep: Same 2-1/8" cross bore, 2-3/4" standard backset direct door prep compatibility

Key systems: Everest and C keyway, SFIC, FSIC compatible

Trim: Heavier lever chassis, larger rose, more trim options

The ALX and ND Series use identical door preparation dimensions. A building that starts with ALX Series on interior offices can specify ND Series on high-traffic main corridors without requiring different door prep. Both series share the same Schlage keyways, so a single key system can cover both ALX and ND hardware throughout the building. This compatibility is one of the primary reasons the Schlage cylindrical lock product line is widely specified in mixed-use commercial projects.

Browse the complete commercial cylindrical lock parts catalog at SecurityParts.com for both ALX and ND Series parts and diagrams.

Schlage ALX Series Key and Cylinder Options

Everest Keyway

The Everest keyway is Schlage's restricted key system for the ALX Series. Everest keys are patented and cannot be duplicated at hardware stores or standard key shops without authorization from the building owner or key system manager. This key control protection is built into the key itself, not just the cylinder, making it significantly more resistant to unauthorized key copying than a standard commercial keyway.

Everest is the recommended keyway specification for new construction projects where key control is a priority and the building owner wants to maintain control over who can have keys made. For the key system management process that governs how master keys, submaster keys, and individual change keys are issued across a building, see the Schlage key systems guide at SecurityParts.com.

C Keyway

The standard C keyway is the most widely used Schlage commercial cylinder keyway and is available at most key shops. It is the correct specification for projects joining an existing C-keyway master key system, or where key duplication convenience is a priority over key control. The C keyway is compatible with the full Schlage ALX Series function range.

SFIC (Small Format Interchangeable Core)

SFIC cylinders allow the key core to be removed and replaced with a control key without disassembling the lock from the door. In SFIC buildings, the facility manager can rekey every ALX Series lock in the building in a single pass using only the control key, without calling a locksmith. SFIC compatibility is available on most ALX Series function codes and is commonly specified in healthcare and education facilities where rekeying the building must be completed quickly between tenants or following a security incident.

Schlage ALX Series OEM Replacement Parts

Schlage hardware OEM parts for ALX Series cylindrical locks at SecurityParts.com

When a Schlage ALX Series cylindrical lock requires service, the correct specification is always OEM Schlage parts. Aftermarket components are not manufactured to the ANSI A156.2 Grade 2 tolerances the ALX mechanism depends on and may produce inconsistent latch engagement, premature wear, or mechanism failure. On fire-rated openings, non-OEM parts can invalidate the UL listing of the door assembly.

Most Commonly Replaced ALX Series Parts

Latch bolt assembly the most common mechanical replacement, worn from repeated latch-to-strike contact on misaligned doors

Lever trim and rose worn, damaged, or finish-matched replacement on renovation projects

Strike plate ANSI T-strike in standard or box strike configuration, replaced when damaged or when the door edge shifts from frame settlement

Cylinder and core replacement for lost-key situations, rekeying after a security incident, or conversion to SFIC

Spindle the connecting bar between outside and inside lever trim, occasionally bent from lever abuse

Through-bolts stripped or missing mounting screws that cause the trim to loosen from the door face

Browse OEM Schlage ALX Series parts at the Schlage ALX Series parts and diagrams page. The interactive diagram on the product page identifies each component by its position in the assembly so you can confirm the correct part before ordering. See also the complete commercial cylindrical locks guide for specification guidance across the full Schlage cylindrical lock range.

Why Choose SecurityParts.com for Schlage ALX Series Parts

SecurityParts.com has supplied commercial door hardware parts since 2001. The Schlage ALX Series product page includes an interactive parts diagram that shows every component of the lock by location so you can identify the failed part visually before ordering. OEM Schlage ALX parts for lever trim, latch assemblies, cylinders, strike plates, and spindles ship same day from SecurityParts.com.

Browse the Schlage ALX Series parts and diagrams, the complete Schlage hardware parts catalog, the commercial cylindrical lock parts catalog, and all SecurityParts.com commercial door hardware parts. Call 845-935-0301 or visit the SecurityParts.com contact page for parts identification and same-day shipping support. The Schlage ALX Series guide is one of several Schlage resources at SecurityParts.com see also the Schlage key systems guide for master key system planning across ALX and ND Series installations.

This Schlage ALX Series guide covers the complete function code range, the Schlage ALX template door preparation dimensions, in-field function change procedure, and OEM parts resources. It is maintained by the commercial door hardware team at SecurityParts.com. For ALX Series parts identification, specification support, or same-day shipping, call 845-935-0301 or browse the Schlage ALX Series parts catalog at SecurityParts.com.

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ANSI BHMA Hardware Standards Guide: Grade 1 vs 2 vs 3 and A156 Series Explained Wednesday, July 22, 2026

ANSI/BHMA grades (1, 2, 3) measure door hardware performance through independently verified testing by BHMA-accredited laboratories. Grade 1 is the highest, required for most commercial applications. The A156 series is the family of standards that defines what Grade 1 means for each hardware type: A156.2 (cylindrical locks, 1,000,000 cycles Grade 1), A156.13 (mortise locks, 1,000,000 cycles Grade 1), A156.3 (exit devices, 500,000 cycles Grade 1 with preload since 2014), A156.4 (door closers, 2,000,000 cycles Grade 1), A156.12 (interconnected locks), A156.5 (general cylinders), A156.30 (high-security cylinders). BHMA certification is not self-reported: each product is independently tested. Every Schlage ND Series, Von Duprin 98/99, and LCN 4040XP part at SecurityParts.com carries ANSI/BHMA Grade 1 certification under the applicable A156 standard.

The ANSI/BHMA grading system is the universal language of commercial door hardware specification. Architects write it into hardware schedules. Contractors verify it at bid time. Facility managers use it to confirm maintenance replacements meet the original specification. But the grade number alone ("Grade 1") is meaningless without knowing which A156 standard it applies to, because Grade 1 means something very different for a cylindrical lock (1,000,000 cycles) versus an exit device (500,000 cycles with preload) versus a door closer (2,000,000 cycles). This guide maps every major A156 standard to the hardware it covers, explains what each grade actually requires, and identifies the specification errors that create quality floors lower than intended.

For ANSI/BHMA Grade 1 certified OEM parts at SecurityParts.com, browse Schlage ND Series cylindrical lock parts (A156.2 Grade 1), Schlage L Series mortise lock parts (A156.13 Grade 1), Von Duprin exit device parts (A156.3 Grade 1), LCN door closer parts (A156.4 Grade 1), and the complete Allegion hardware catalog.

40+ Number of individual ANSI/BHMA A156 standards currently maintained by BHMA

Independent BHMA certification is not self-reported: products are tested by BHMA-accredited independent laboratories

2014 Year the A156.3 exit device standard added preload requirement to Grade 1 cycle testing

A156 only ANSI alone is not a standard; the A156 number is required in any valid hardware specification

What BHMA Is and How Certification Actually Works

BHMA (the Builders Hardware Manufacturers Association) is the trade organization for North American commercial door hardware manufacturers and the only organization accredited by the American National Standards Institute (ANSI) to develop and maintain performance standards for commercial builders hardware. ANSI is the accrediting body for the standards development process; it does not write the standards itself. When a standard is designated ANSI/BHMA, BHMA wrote it and ANSI verified that the development process met the requirements for an American National Standard.

BHMA maintains over 40 individual standards, each covering a specific hardware category. These standards define test methods, performance requirements (including cycle counts, force resistance, and security tests), dimensional criteria for interchangeability, and grade thresholds. They are updated on a rolling cycle: ANSI requires standards to be reviewed every five years, and when tests or requirements change, the revision year appears in the standard designation (for example, A156.3-2025 vs A156.3-2014).

How BHMA Certification Is Administered

BHMA certification is not self-reported by manufacturers. When a manufacturer wants to certify a product, the product is submitted to a BHMA-accredited independent testing laboratory. The laboratory conducts the applicable tests from the relevant A156 standard and reports the results to BHMA. If the product passes all required tests for a grade, BHMA issues certification. Products that carry BHMA certification have been independently verified to the stated grade. Products that claim grade equivalency without BHMA certification have not been independently verified and cannot be confirmed to meet the stated grade requirements.

The certification verification step that most facility managers skip when approving substitutions: When a contractor or supplier proposes a substituted hardware product as "ANSI Grade 1 equivalent," the verification step is to confirm the product's BHMA certification number in the BHMA certified products directory (available at buildershardware.com). A product that claims Grade 1 performance without a valid BHMA certification number has not been independently tested. Many cheaper commercial hardware products sold with Grade 1 claims on their packaging are not BHMA certified and have not been tested to A156 Grade 1 requirements. The BHMA directory lookup takes less than two minutes and is the only reliable verification method.

The Three ANSI/BHMA Grades: What They Mean Across All Hardware Types

Grade 1

Highest Performance Commercial

Required for exterior doors, high-traffic corridors, institutional applications (schools, hospitals, government), and any opening where maximum durability and security are specified. The IBC and most specifications require Grade 1 on primary egress paths and secured doors. Schlage ND Series, Von Duprin 98/99 series, and LCN 4040XP are Grade 1 certified products.

Grade 2

Moderate Commercial Performance

Suitable for low-traffic interior commercial doors, office suites, storage rooms, and light-duty applications where the door is used infrequently. Not specified for exterior doors, fire-rated doors in high-traffic areas, or any opening on a primary egress path in an institutional building. Acceptable in some residential multifamily interior applications where the door hardware is interior and protected.

Grade 3

Light Residential

Residential application only. Grade 3 hardware should not appear in any commercial specification. It meets minimum residential performance requirements that are far below commercial durability and security needs. If Grade 3 hardware is installed in a commercial building, it will fail prematurely and may not meet any applicable code requirements for commercial hardware performance.

Key ANSI/BHMA A156 Standards by Hardware Type

A156.2 Bored and Preassembled Locks and Latches (Cylindrical Locks)

A156.2 covers cylindrical (bored) locks, the type that installs into a bore hole in the door face. This is the standard for Schlage ND Series, ALX Series, and Falcon T Series cylindrical locks. Tests include cycle testing, torque resistance, door impact testing, security testing (resistance to forced entry), and finish testing.

Grade	Cycle Count	Door Impact Resistance	Typical Application
Grade 1	1,000,000 cycles	360 lbf	Commercial, institutional, high-traffic
Grade 2	800,000 cycles	250 lbf	Light commercial, low-traffic interior
Grade 3	400,000 cycles	150 lbf	Residential only

Browse Schlage ND Series and ALX Series A156.2 Grade 1 cylindrical lock parts at Security Parts.

A156.13 Mortise Locks and Latches

A156.13 covers mortise locks, which install into a rectangular pocket cut into the door edge. This is the standard for Schlage L Series and Falcon MA Series mortise locks. Tests include operational tests for each lock function, cycle testing, strength tests, security tests, a warped door test, and finish testing. The warped door test simulates a bowed door pushing the latch against the strike, which is common in wood door applications.

Grade	Cycle Count	Key Notes
Grade 1	1,000,000 cycles	Includes warped door test; required for commercial and institutional applications
Grade 2	800,000 cycles	Moderate commercial only
Grade 3	No commercial use	Residential standard, not for commercial specification

Browse Schlage L Series and Falcon MA Series A156.13 Grade 1 mortise lock parts at Security Parts.

The A156.13 warped door test that distinguishes mortise from cylindrical standards: A156.13 includes a warped door test that A156.2 does not. The warped door test applies a lateral force to the door that simulates a bowed or twisted door pressing the latch against the strike continuously while the latch is cycled. This test reflects a common real-world condition for mortise locks in wood door applications where seasonal wood movement warps the door over years of use. A Grade 1 mortise lock that passes the warped door test under full load has demonstrated its latch will continue to function in conditions that would cause many locks to bind or fail. This test is one reason Grade 1 mortise locks are specified for institutional wood door applications in schools and healthcare where door warpage over the building lifecycle is expected.

A156.3 Exit Devices

A156.3 covers exit devices (panic hardware and fire exit hardware). Tests include cycle testing, force tests (maximum 15 lbf to unlatch), and endurance standards. Exit devices on fire-rated doors must also carry a UL or WHI fire listing in addition to their A156.3 Grade 1 certification. The 2014 revision added a preload requirement to the Grade 1 cycle test.

Grade	Cycle Count	Preload Requirement (post-2014)	Force to Unlatch
Grade 1	500,000 cycles	Yes: 20 to 22 lbf applied to door during cycling	15 lbf max
Grade 2	250,000 cycles	No preload required	15 lbf max
Grade 3	100,000 cycles	No preload required	15 lbf max

Browse Von Duprin 98/99, 22, 33A/35A A156.3 Grade 1 exit device parts at Security Parts.

A156.4 Door Controls (Closers)

A156.4 covers door closers. Tests define closing force ranges (sizes 1 through 6), backcheck performance, sweep and latch speed, and cycle testing. Door closers have the highest cycle count requirements of any A156 standard because closers operate on every single door cycle including push and pull sides simultaneously. The LCN 4040XP carries A156.4 Grade 1 certification and is rated to 10,000,000 cycles by LCN internal testing, far exceeding the A156.4 Grade 1 minimum.

Grade	Cycle Count	Typical Application
Grade 1	2,000,000 cycles (standard minimum)	All commercial and institutional; required on fire-rated doors
Grade 2	1,000,000 cycles	Light commercial, low-traffic interior
Grade 3	500,000 cycles	Residential; not for commercial specification

Browse LCN 4040XP, 4000 Series, and 1000 Series A156.4 Grade 1 door closer parts at Security Parts.

A156.12 Interconnected Locks

A156.12 covers interconnected locks including the Schlage CS210 series, where the deadbolt and latch bolt are mechanically linked so that a single lever motion retracts both. The CS210 is certified to ANSI/BHMA A156.12-2022 Grade 2, making it the correct specification for multifamily residential applications where NFPA 101 single-motion egress is required but Grade 1 institutional performance is not. Tests include cycle testing, deadbolt throw testing, and force testing for the simultaneous retraction mechanism.

Browse Schlage CS210 A156.12 Grade 2 interconnected lock parts at Security Parts.

Additional A156 Standards: Cylinders, High Security, and Electrified Hardware

A156.5: Cylinders and Input Devices

A156.5 covers general commercial cylinders, key control, and related input devices. This is the standard for standard cylindrical lock cylinders, mortise cylinders, and rim cylinders in conventional and interchangeable core formats. Tests include key interchange testing, key duplication resistance (for restricted keyways), and cycle testing of the cylinder mechanism. The Schlage Everest 29 cylinder series and SFIC and FSIC interchangeable core products are certified under A156.5.

A156.30: High-Security Cylinders

A156.30 is a separate and more demanding standard specifically for high-security cylinders. Where A156.5 tests general cylinder function and basic key control, A156.30 tests cylinders specifically for resistance to physical attacks: picking, drilling, impressioning, and pull attacks. Cylinders certified under A156.30 have passed specific attack resistance tests that general A156.5 cylinders have not.

The Schlage Primus and Primus XP cylinders are the relevant A156.30 products in the SecurityParts.com catalog. A specification that requires high-security cylinder performance must cite A156.30, not A156.5. Citing A156.5 for a project that needs pick and drill resistance allows standard cylinders to satisfy the specification because A156.5 does not require attack resistance testing.

A156.25: Electrified Locks

A156.25 covers electrified mortise locks and cylindrical locks. When a Schlage L Series or ND Series lock is ordered in an electrified version (EL, EU, or similar suffix), the electrical components are governed by A156.25 in addition to the base mechanical standard (A156.13 for mortise, A156.2 for cylindrical). Tests include electrical performance, cycle testing with the electrical function activated, and temperature testing of the electrical components. A specification for an electrified lock must cite both the mechanical standard (A156.13 or A156.2) and A156.25 for complete coverage.

Browse Von Duprin electric strike parts and the electrified hardware catalog at Security Parts.

The 2014 A156.3 Exit Device Preload Change: Why It Matters Today

The 2014 revision of ANSI/BHMA A156.3 made a significant change to the Grade 1 cycle test that affects how older hardware certifications should be interpreted. Before 2014, the exit device cycle test operated the device without any load applied to the door during cycling. The latch was simply cycled in free air. After 2014, the Grade 1 cycle test requires applying a preload force (20 to 22 lbf) to the door during cycling, simulating the actual load the latch must overcome with each cycle in real use.

This preload requirement substantially increases the difficulty of the Grade 1 cycle test. A device designed and tested to the pre-2014 standard may have achieved Grade 1 certification without ever demonstrating reliable performance under the load conditions it faces in actual building use. Products certified as Grade 1 under the 2008 or earlier edition of A156.3 may not meet the current Grade 1 preload cycle test requirements.

The pre-2014 certification that no longer meets current Grade 1 standards: This affects any exit device specification that cites "ANSI/BHMA A156.3 Grade 1" without specifying the edition year. An older product certified to the 2008 edition technically complies with a spec that cites the standard without an edition year, because the standard number without a year does not specify which edition applies. A specification that requires the current Grade 1 standard must cite A156.3-2025 (current edition) or A156.3-2022 (previous). Von Duprin's current 98/99 and related series products are certified to the current edition of A156.3. When verifying whether a proposed substitute exit device meets the current Grade 1 standard, confirm the BHMA certification year, not just the grade.

Common ANSI/BHMA Specification Errors That Reduce Quality Floors

Error 1: Citing Grade Without the Standard Number

Incorrect: "Provide Grade 1 mortise locks."

Without the A156 number, "Grade 1" refers to no specific test standard. A manufacturer could argue that any hardware rated Grade 1 under any A156 standard satisfies this specification, including less demanding standards.

Correct: "Provide mortise locks certified to ANSI/BHMA A156.13-2022 Grade 1." The standard number, edition year, and grade together create an unambiguous quality floor.

Error 2: Specifying High-Security Cylinders Under A156.5

Incorrect: "Cylinders shall be ANSI/BHMA A156.5 Grade 1 with restricted keyway."

A156.5 covers general cylinders. It does not include attack resistance testing. A restricted keyway provides key control (key duplication restriction) but a standard cylinder with a restricted keyway has not been tested for picking or drilling resistance.

Correct: "High-security cylinders shall be certified to ANSI/BHMA A156.30." A156.30 requires specific pick, drill, and pull attack resistance testing that A156.5 does not.

Error 3: Specifying Electrified Locks Without A156.25

Incorrect: "Electrified mortise locks shall be ANSI/BHMA A156.13 Grade 1."

A156.13 covers the mechanical function of the mortise lock. Electrified locks have additional electrical components (solenoid, wiring, connectors) that A156.13 does not test. The electrical performance requirements are in A156.25.

Correct: "Electrified mortise locks shall be certified to ANSI/BHMA A156.13-2022 Grade 1 and A156.25 for electrified hardware." Both standards must be cited for complete coverage.

Error 4: Using Residential Standards in Commercial Projects

Incorrect: Allowing products certified to A156.39 or A156.40 in a commercial specification.

A156.39 and A156.40 are residential lockset and deadbolt standards. Their performance requirements are substantially lower than A156.2 and A156.13 commercial standards. Residential hardware in commercial buildings will fail prematurely and may not meet applicable code requirements.

Correct: Explicitly specify A156.2 (cylindrical) or A156.13 (mortise) in all commercial hardware schedules. "Commercial grade" language without the A156 number does not prevent residential-standard products from being substituted.

Error 5: Missing the Edition Year on Exit Device Specifications

Incorrect: "Exit devices shall be ANSI/BHMA A156.3 Grade 1."

Without the edition year, the specification is satisfied by products certified to any edition of A156.3, including pre-2014 editions that did not require the preload cycle test for Grade 1.

Correct: "Exit devices shall be certified to ANSI/BHMA A156.3-2025 Grade 1." The current edition ensures the preload cycle test requirement is met.

A156 Standards Reference Table for Security Parts Hardware

A156 Standard	Hardware Type	Grade 1 Cycle Count	Applicable Product	Browse at SecurityParts.com
A156.2	Cylindrical locks	1,000,000 cycles	Schlage ND Series, ALX, Falcon T Series	Cylindrical Lock Parts
A156.13	Mortise locks	1,000,000 cycles	Schlage L Series, Falcon MA Series	Mortise Lock Parts
A156.3	Exit devices	500,000 cycles (with preload)	Von Duprin 98/99, 22, 33A/35A, 55, 75, 78, 88	Exit Device Parts
A156.4	Door closers	2,000,000 cycles	LCN 4040XP, 4000 Series, 1000 Series	Door Closer Parts
A156.12	Interconnected locks	Grade 2	Schlage CS210	Interconnected Lock Parts
A156.5	General cylinders	Varies by type	Schlage Everest 29, SFIC, FSIC	Schlage Hardware
A156.30	High-security cylinders	Plus attack resistance tests	Schlage Primus, Primus XP	Schlage Hardware
A156.1	Hinges and butts	Grade 1 weight and cycle tests	Fire-listed steel hinges for fire doors	All Products

For pre-order ANSI grade and A156 standard verification support at 845-935-0301 or the contact page.

Why Choose SecurityParts.com for ANSI/BHMA Grade 1 Certified Hardware Parts

BHMA certification verification support, A156.3 preload edition year guidance, A156.30 high-security distinction, electrified hardware A156.25 specification, and same-day OEM shipping.

A156.3 Edition Year Guidance

We document the 2014 A156.3 preload change and why exit device specifications without edition years allow pre-2014 products to satisfy current Grade 1 requirements. Von Duprin current production is certified to the current A156.3 edition.

A156.30 vs A156.5 Distinction

We document that high-security cylinder specifications must cite A156.30, not A156.5. This prevents standard cylinders from satisfying specifications that require pick and drill resistance testing under a correctly written A156.30 citation.

BHMA Certification Verification

We document how to verify BHMA certification through the BHMA certified products directory. All Allegion brand products at SecurityParts.com carry current BHMA certification under the applicable A156 standard for their grade.

Same-Day OEM Shipping

ANSI/BHMA Grade 1 certified Allegion parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for A156 standard and grade confirmation support.

What Makes Security Parts Different for ANSI/BHMA Standards Compliance

We document the 2014 A156.3 exit device preload requirement change and explain why exit device certifications without edition years may allow pre-2014 Grade 1 products that have not been tested under preload conditions. No other parts supplier documents the edition year significance at the product ordering level.
We document the A156.30 vs A156.5 distinction for high-security cylinder specification. Specifying A156.5 when A156.30 is intended creates a specification gap that allows standard cylinders with restricted keyways to satisfy a specification intended to require attack resistance testing. This error is common in master specifications and is not documented by any competitor.
We document the BHMA certified products directory as the verification tool for grade claims and explain that BHMA certification is independently tested, not self-reported. This is the fact that distinguishes verifiable Grade 1 hardware from marketing claims.
We document the A156.13 warped door test as the distinguishing test between mortise and cylindrical lock standards, and explain why it matters for institutional wood door applications where door warpage over the building lifecycle is expected.
All Allegion brand parts at SecurityParts.com carry current BHMA certification under the applicable A156 standard. Browse cylindrical locks, mortise locks, exit devices, and door closers at Security Parts.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Frequently Asked Questions About ANSI/BHMA Door Hardware Standards

What is BHMA and what is its relationship to ANSI?

BHMA (Builders Hardware Manufacturers Association) is the only organization accredited by ANSI to develop and maintain performance standards for commercial builders hardware. ANSI is the accrediting body; BHMA develops the standards. When a standard is designated ANSI/BHMA, it means BHMA wrote the standard and ANSI verified the development process. BHMA administers product certification through accredited independent testing laboratories. Certification is not self-reported by manufacturers: products must be tested by an independent BHMA-accredited laboratory to carry BHMA certification.

What are the three ANSI/BHMA grades and what cycle counts do they require?

Grade 1 (highest), Grade 2 (moderate), Grade 3 (residential). Cycle counts vary by hardware type: cylindrical locks (A156.2): Grade 1 requires 1,000,000 cycles; mortise locks (A156.13): Grade 1 requires 1,000,000 cycles; exit devices (A156.3): Grade 1 requires 500,000 cycles with preload; door closers (A156.4): Grade 1 requires 2,000,000 cycles. Grade 1 is the commercial specification for exterior, high-traffic, institutional, and security-sensitive openings. Grade 3 should not appear in any commercial specification.

What changed in the 2014 ANSI/BHMA A156.3 exit device standard revision?

The 2014 revision added a preload requirement to the Grade 1 cycle test. Before 2014, exit devices were cycled without load. After 2014, Grade 1 testing requires applying 20 to 22 lbf to the door during cycling, simulating real-use conditions. Products certified to the 2008 edition may not meet current Grade 1 preload requirements. Specifications must cite the current edition (A156.3-2025) to ensure preload testing applies. Von Duprin current production exit devices are certified to the current A156.3 edition.

What is the difference between ANSI/BHMA A156.2 and A156.13?

A156.2 covers cylindrical (bored) locks that install into a door bore hole. This is the standard for Schlage ND Series and ALX Series. A156.13 covers mortise locks installed in a mortise pocket at the door edge. This is the standard for Schlage L Series and Falcon MA Series. Both require 1,000,000 cycles at Grade 1, but A156.13 includes a warped door test not in A156.2, reflecting the different mechanical design and common application conditions of mortise vs cylindrical locks.

What is ANSI/BHMA A156.30 and why is it different from A156.5 for high-security cylinders?

A156.5 covers general commercial cylinders without attack resistance testing. A156.30 is the high-security cylinder standard requiring specific pick, drill, impressioning, and pull attack resistance tests. A specification that cites A156.5 for "high-security" cylinders allows standard cylinders with restricted keyways to satisfy it because A156.5 has no attack resistance requirements. Schlage Primus and Primus XP cylinders are the A156.30 products in the SecurityParts.com catalog. Always cite A156.30 explicitly when attack resistance is required.

How do I read an ANSI/BHMA certification label on commercial door hardware?

A complete citation includes the standard number, edition year, and grade: for example, ANSI/BHMA A156.2-2022 Grade 1 for a cylindrical lock. The standard number identifies the hardware type. The edition year identifies which test requirements applied. The grade identifies the performance tier. A citation without the edition year is incomplete: different editions have different test requirements, and the 2014 A156.3 preload change is a concrete example of why edition years matter. Verify BHMA certification in the BHMA certified products directory at buildershardware.com before approving substitutions.

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Von Duprin Panic Bar QEL vs MEL: How to Choose the Right Electric Latch Retraction for Your Opening Wednesday, July 22, 2026

When a Von Duprin panic bar needs to open from the outside on an access control credential, two electrified options handle that function at the device level: QEL (Quiet Electric Latch Retraction) and MEL (Motorized Electric Latch Retraction). They both retract the latch bolt on a signal from the access control panel, but they work differently mechanically, draw power differently, and produce different acoustic signatures during operation. Choosing the wrong one does not create a safety problem, but it does create an operational or acoustic mismatch that is expensive to correct after installation. This guide explains how each works, which Von Duprin series support each, and exactly when to specify one over the other.

The Von Duprin panic bar electrified options discussed in this guide are available on the series stocked at SecurityParts.com. Browse the complete Von Duprin exit device and panic bar catalog and the full Von Duprin parts and series guide. For specification support before ordering, call 845-935-0301 or visit the SecurityParts.com contact page.

Von Duprin exit device electrified options : QEL and MEL for access control integration at the panic bar level

What QEL and MEL Do and Why They Exist

A standard mechanical Von Duprin panic bar allows egress from the inside by pressing the push bar. It does not allow entry from the outside unless the door is equipped with a separate outside trim function (lever, knob, or thumbturn) that retracts the latch from the exterior. On openings requiring controlled outside access, the most common solution historically was an electric strike in the frame that releases on an access grant signal. That is a frame-side solution.

QEL and MEL are device-side solutions. They retract the latch bolt inside the Von Duprin panic bar itself when an access grant signal is received, instead of releasing the keeper in the frame. The door swings open under push or pull without any secondary hardware in the frame. This matters for a few reasons: it works on hollow metal frames where installing an electric strike requires a cut that voids the frame's fire rating on rated assemblies, it preserves the full security engagement of the mechanical latch during normal locked conditions, and it simplifies the overall hardware schedule on a complex opening.

The Outside Trim Question

QEL and MEL retract the latch. They do not provide a pulling handle on the outside. A Von Duprin panic bar with QEL still requires an outside trim component for the user to physically pull the door open after the latch retracts. Outside trim options include levers, knobs, pulls, and thumbturns, available in a range of functions depending on the access control integration required. The trim function is specified separately from the QEL or MEL configuration and must be compatible with the outside trim options available for the specific series.

How QEL Works vs How MEL Works

QEL : Quiet Electric Latch Retraction

Solenoid-driven latch retraction

Mechanism: Electromagnetic solenoid pulls a plunger that retracts the latch bolt when energized. Operates on 12VDC or 24VDC.

Speed: Instantaneous retraction on signal. Latch retracts in milliseconds.

Sound: Produces a quiet solenoid click on activation. Noticeably quieter than a frame-side electric strike but audible in very quiet environments.

Current draw: 300 to 500 milliamperes during retraction. Higher inrush current at activation.

Field upgrade: Available as a modular conversion kit for existing mechanical Von Duprin devices. No device removal required.

Availability: 22, 33A/35A, 75, 78, and 98/99 Series.

MEL : Motorized Electric Latch Retraction

Motor-driven latch retraction

Mechanism: Small motor drives a gear assembly that retracts the latch bolt. Operates on 24VDC.

Speed: Slightly slower retraction than QEL. Typically 1 to 2 seconds from signal to full retraction.

Sound: Near-silent operation. The motor produces a low hum that is inaudible at normal ambient sound levels. Preferred for acoustically sensitive environments.

Current draw: Lower sustained current draw than QEL solenoid. More consistent current profile without inrush spike.

Field upgrade: Factory-configured option. Not available as a field conversion kit for existing mechanical devices.

Availability: 98/99, 33A/35A, and 75 Series only.

Which Von Duprin Series Support QEL and MEL

Not every Von Duprin panic bar series supports electric latch retraction. The 55 and 88 crossbar series are mechanical-only by design, with no electrified options at the device level. Every other active series in the Von Duprin lineup supports QEL. MEL is available on a narrower set of series.

SeriesQELMELNotes
98/99 SeriesYes YesWidest electrified options catalog. QEL modular field conversion available. MEL factory-configured.
33A/35A SeriesYes YesNarrow-stile touchbar for aluminum storefronts. QEL modular field kit available. MEL factory-configured.
75 SeriesYes YesStandard commercial Grade 1. QEL modular field conversion available. MEL factory-configured.
22 SeriesYes NoMid-range commercial. QEL modular field conversion available. MEL not supported.
78 SeriesYes NoNarrow-stile push pad. QEL modular field conversion available. MEL not supported.
55 SeriesNo NoCrossbar, mechanical-only. No electrified options at device level.
88 SeriesNo NoCrossbar, mechanical-only. No electrified options at device level.

Specifying the 98/99 Series on new construction protects future electrified upgrade paths. A mechanical 98/99 device installed today can be upgraded to QEL years later using the modular conversion kit, without removing the device from the door or patching any frame or door prep. This forward compatibility is why the 98/99 is consistently specified on institutional openings even when access control is not in the current project scope. The upgrade option remains available for the life of the building.

The QEL Modular Conversion Kit: Upgrading a Mechanical Von Duprin Panic Bar to Electric

Von Duprin 98/99 Series panic bar : supports QEL modular field conversion without device removal

The QEL modular conversion kit is the feature that makes electric latch retraction practical as a retrofit on existing Von Duprin panic bars. The kit replaces the dogging cover plate on the mechanism case and integrates a solenoid assembly that connects to the latch retraction mechanism inside the existing case. The device does not come off the door. The frame does not get cut. The installation typically takes under an hour per opening.

The conversion kit requires a power supply connection to the device and a signal connection from the access control panel's lock output. Once wired, the panic bar operates identically to a factory-configured QEL unit: the latch is mechanically extended and the door is locked under normal conditions, and the latch retracts when the access control panel sends a signal.

What the QEL Modular Kit Includes

The kit includes the solenoid assembly, the modified dogging cover, the solenoid mounting hardware, and the wiring connections that integrate the solenoid with the existing mechanism case. Series-specific kits are required because the mechanism case dimensions and dogging cover geometry differ between the 22, 33A/35A, 75, 78, and 98/99 Series. Always order the kit designated for the exact series installed on the door.

The QEL conversion kit does not include outside trim. Outside trim must be specified separately based on the function required at the opening: entry control only (pull or blank escutcheon outside), keyed outside entry (cylinder outside), or lever/knob for two-direction traffic with credential control provided only by the QEL signal.

When to Specify QEL and When to Specify MEL

Specify QEL When

The opening is a standard commercial corridor, stairwell, or employee entrance where solenoid click is not an acoustic concern
A retrofit upgrade is being done on an existing mechanical Von Duprin device and MEL is not an option for the installed series
12VDC power is available and a 24VDC supply would require additional wiring or power supply changes
The project is specifying the 22 or 78 Series where MEL is not supported
Budget is a primary constraint and QEL is specified at a lower cost than MEL at the factory configuration level

Von Duprin 22 Series panic bar : supports QEL only, not MEL

Specify MEL When

The opening is in an acoustically sensitive environment where solenoid click is audible and disruptive: intensive care units, operating suites, neonatal units, executive offices, recording studios, or libraries
The project specification calls for silent hardware operation at all electrified openings
The access control system cycles the lock output frequently (high-credential-volume openings) and solenoid noise accumulation across many daily activations is a concern
The opening is on the 98/99, 33A/35A, or 75 Series where MEL is a supported factory option
The project is new construction or a full hardware replacement where factory configuration is available

Von Duprin 33/35A Series touchbar panic bar : supports both QEL and MEL for aluminum storefront access control applications

MEL is not available as a field conversion kit on existing devices. MEL requires factory configuration because the motor assembly integrates into the mechanism case in a way that cannot be replicated with a field retrofit kit. If an existing mechanical Von Duprin panic bar needs to be upgraded to motorized operation, the device must be replaced with a factory-configured MEL unit. For a field upgrade, QEL is the only option.

QEL and MEL on Fire-Rated Von Duprin Panic Bars

Both QEL and MEL are fully compatible with fire-rated Von Duprin panic bar configurations. The fire rating is determined by the device model suffix ("-F") and the UL listing of the complete assembly, not by whether the device includes an electric option. A 98-F QEL or 98-F MEL device carries the same UL fire rating as a mechanical 98-F device.

The critical point on fire-rated openings: QEL and MEL operate fail secure. The latch is extended and the door is latched whenever power is absent. A power failure does not release the fire door. This is the correct and required configuration for fire-rated assemblies per NFPA 80. Fail safe operation, where power failure would cause the door to release, is not available on Von Duprin exit devices and is specifically prohibited by NFPA 80 on fire-rated doors.

Do not confuse electric latch retraction with electric dogging on fire-rated doors. QEL and MEL retract the latch bolt to allow entry on a credential signal, which is compliant on fire-rated openings. Electric dogging holds the push bar in the depressed position to hold the door open, which is NOT compliant on fire-rated doors. Fire-rated Von Duprin devices carry the "-F" suffix specifically because the dogging function is removed. If a fire door needs to be held open operationally, an electromagnetic holder connected to the fire alarm is the correct solution, not an electric dogging configuration.

Companion Electrified Options: Chexit and ALK

Chexit Delayed Egress

Chexit is a Von Duprin electrified option that holds the door latched for 15 seconds after the push bar is pressed, while sounding a local alarm during the delay. At the end of 15 seconds, the latch retracts and the door opens. Chexit is not an access control function and does not work from a credential at the outside. It is an egress deterrence function specified on secondary exits to reduce unauthorized egress without preventing emergency exit.

Chexit and QEL or MEL serve different functions and are not substitutes. A single opening may have both: QEL or MEL providing access-controlled entry from the outside, and Chexit providing egress deterrence from the inside on the same push bar. This configuration is common on pharmaceutical storage rooms, secured data areas, and behavioral health wings in healthcare facilities.

ALK Alarm Exit Kit

The Von Duprin ALK alarm exit kit converts the standard panic bar push bar to an alarmed exit device. When the push bar is pressed, an 85-decibel alarm sounds from a battery-powered alarm module. The alarm is controlled by a mortise cylinder: turning the cylinder to the locked position enables the alarm, turning it to the unlocked position silences it for authorized egress. The ALK kit does not require a power supply connection and does not integrate with the access control system.

ALK is a standalone deterrence tool, not an access control integration. It is specified on secondary exits where budget does not support a full QEL or MEL installation but where some deterrence against unauthorized door use is required. For openings requiring both alarm deterrence and access control integration, the RX signal switch on a QEL or MEL device provides the event logging function while a separate alarm system handles the audio deterrence.

Power Requirements and Wiring for QEL and MEL

Power Supply Requirements

Both QEL and MEL require DC power. QEL devices are available in 12VDC and 24VDC configurations. MEL devices operate on 24VDC only. A dedicated regulated DC power supply, separate from the access control panel's internal supply, is required. The QEL solenoid draws approximately 300 to 500 milliamperes during latch retraction with a higher inrush current at the moment of activation. The MEL motor draws lower sustained current than the QEL solenoid and does not have the same inrush spike.

RX Request to Exit Switch

The RX (Request to Exit) switch is a micro switch inside the push bar that signals the access control panel when someone presses the push bar from the inside for egress. On QEL and MEL configured devices, the RX switch prevents the access control panel from generating a door-forced alarm every time an authorized user exits through the push bar. Without the RX signal, the panel sees the door opening without receiving a credential input and flags it as an unauthorized event.

The RX function is available on the 98/99, 33A/35A, 22, and 75 Series. It is wired on a separate low-voltage signal circuit from the QEL or MEL power circuit. Always specify the RX option on any QEL or MEL configured opening where the access control system monitors door events.

Von Duprin 75 Series panic bar : supports QEL and MEL, commonly specified for healthcare and standard commercial applications

QEL vs MEL vs Electric Strike: Choosing Between Device-Side and Frame-Side Solutions

For openings where outside access control is the requirement, facility teams sometimes choose between a QEL or MEL configured Von Duprin panic bar and a Von Duprin electric strike in the frame. Both achieve the same function: the door latches mechanically and unlocks on an access control signal. The choice depends on the door and frame conditions at the specific opening.

A frame-side electric strike is the simpler installation on existing openings where the frame can accept the strike cutout and the frame is not fire-rated in a way that prohibits the cutout. An electric strike does not require wiring to the door itself, which eliminates the need for a power transfer hinge or electrified door loop when the power must cross from the frame to the door-mounted device.

A device-side QEL or MEL configuration is preferred when the frame cutout for a strike would void the frame's fire rating, when the existing door and frame do not have the correct dimensions for an electric strike, or when the specification requires that all hardware maintain the full security engagement of the mechanical Von Duprin latch at the door edge rather than the frame-side keeper engagement of an electric strike.

For a detailed comparison of Schlage motorized latch retraction versus electric strike configurations, see the Schlage L9580 vs electric strike comparison guide at SecurityParts.com, which covers the same device-side vs frame-side decision for mortise lock applications.

Why Choose SecurityParts.com for Von Duprin Electrified Exit Device Parts

SecurityParts.com has supplied commercial door hardware since 2001. The Von Duprin catalog at SecurityParts.com covers the complete electrified exit device lineup including QEL modular conversion kits, MEL factory-configured devices, Chexit assemblies, ALK alarm kits, RX signal switches, and outside trim options for all supported series. Interactive parts diagrams on each model page show every component of the electrified assembly so you can confirm the correct kit before ordering.

For series selection guidance, see the Von Duprin panic bar series selection guide. For parts identification on an installed device, see the Von Duprin panic bar parts identification guide. For code requirements on when panic hardware is required, see the panic hardware code requirements guide. Browse the complete Von Duprin exit device and panic bar catalog, the full Von Duprin parts guide, and all SecurityParts.com commercial door hardware parts. Call 845-935-0301 for specification and same-day shipping support.

This Von Duprin panic bar QEL vs MEL guide is maintained by the commercial door hardware team at SecurityParts.com. For electrified exit device specification support, call 845-935-0301 or browse the Von Duprin exit device and panic bar catalog.

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Commercial Door Fire Rating Guide: 20, 45, 90 Minute and 3 Hour Fire Doors Explained Tuesday, July 21, 2026

Commercial fire door assemblies come in five standard ratings: 20-minute, 45-minute, 60-minute, 90-minute, and 180-minute (3-hour). The required rating is determined by the wall's fire resistance rating: door assemblies are rated at approximately 75 percent of the wall rating. All fire-rated doors regardless of rating must be self-closing, self-latching, and use fire-listed hardware components. Panic hardware (UL 305) is for non-fire-rated doors only. Fire exit hardware (UL 305 plus UL 10C) is required on fire-rated doors where an exit device is needed. Mechanical dogging of fire exit hardware is prohibited: only electric dogging connected to the fire alarm panel is compliant. The current fire testing standard is UL 10C positive pressure, which replaced the older neutral pressure UL 10B test in the late 1990s.

Fire door ratings are specified by architects and required by the IBC and NFPA 101 based on the fire resistance rating of the wall assembly the door protects. Getting the rating right, specifying the correct hardware for that rating, and maintaining that hardware correctly determines whether a fire door performs its function when it is needed. The hardware decisions made at specification time and at every subsequent service call either preserve the assembly's UL listing or silently void it.

Browse fire-listed OEM hardware at SecurityParts.com: Von Duprin fire exit hardware (exit device parts), LCN fire-listed door closer parts, Schlage fire-listed cylindrical lock parts, Schlage L Series fire-listed mortise lock parts, and the complete Allegion fire-listed hardware catalog.

75% Door assembly fire rating is typically 75 percent or less of the wall's fire resistance rating

UL 10C Current positive pressure fire test standard for door assemblies (replaced UL 10B in late 1990s)

Prohibited Mechanical dogging on fire exit hardware: fire doors must positively latch on every closure

3 hinges NFPA 80 minimum for doors up to 90 inches in height: steel, bearing type, fire-listed

How Fire Door Ratings Are Determined

A fire door assembly's required rating is not an arbitrary design decision. It is determined by the fire resistance rating of the wall in which the door is installed, by the applicable building code (IBC or NFPA 101), and by the occupancy type and use of the space. The door cannot be rated the same as the wall because door assemblies are tested under different conditions than wall assemblies and cannot achieve equivalent protection durations.

Wall Rating to Door Rating Relationship

Door assemblies are rated at approximately 75 percent of the fire resistance rating of the surrounding wall. A 2-hour rated fire barrier wall requires a 90-minute (1.5-hour) door: 90 minutes is 75 percent of 2 hours. A 1-hour rated wall typically requires a 45-minute door. A 4-hour rated wall requires a 3-hour door. This relationship is established in NFPA 80 and the IBC Table of Opening Protectives and must be verified against the applicable code edition and local AHJ interpretation, since some jurisdictions require higher ratings than the code minimum.

Wall Fire Resistance Rating	Required Door Rating	Typical Applications
1-hour	45-minute (most corridor applications)	Corridor walls, apartment entry doors, occupancy separations
1.5-hour	60-minute	Exit stairwell enclosures in lower-rise buildings (4 stories or fewer)
2-hour	90-minute	Exit stairwells in mid-rise and high-rise buildings, major occupancy separations
3-hour	3-hour (180-minute)	Building separation walls, major fire area separations
4-hour	3-hour (180-minute)	Firewall separations between buildings or very large fire areas

The 20-minute corridor door that surprises most facility managers: A 20-minute fire door is required in corridor walls rated at 1 hour in many occupancy groups in sprinklered buildings. The IBC and NFPA 101 permit reduced corridor wall ratings (and therefore reduced door ratings) in sprinklered buildings. This means a large office building corridor can have 20-minute rated doors throughout even though the stairwell doors in the same building require 60 or 90 minutes. The confusion arises when a replacement door or hardware is specified without confirming the door schedule. Installing a 45-minute rated replacement for a 20-minute opening is compliant (the higher rating is permitted). Installing a 20-minute replacement for a 45-minute opening is a code violation.

UL 10C Positive Pressure Testing: The Current Standard

All current fire door hardware carries listings under UL 10C (Positive Pressure Fire Tests of Door Assemblies). Understanding why positive pressure matters explains why older hardware that was acceptable under the neutral pressure test (UL 10B) may not provide equivalent real-world protection.

In a building fire, combustion gases and fire-driven air create positive pressure on the fire side of a door assembly: the pressure pushes outward against the door and its seals. Under the old neutral pressure test (UL 10B), the test chamber maintained atmospheric pressure conditions, which did not simulate this fire-driven outward pressure. Hardware and seals that passed the neutral pressure test could fail under the actual positive pressure conditions of a real fire because they were not tested against the outward force the fire itself creates.

UL 10C tests door assemblies under positive pressure from the fire side, simulating the actual conditions the assembly will face. Hardware listed under UL 10C has demonstrated its ability to keep the door closed and latched against fire-driven positive pressure. The transition to positive pressure testing occurred in the late 1990s. Hardware manufactured and installed before this transition carries UL 10B listings. Hardware manufactured since then carries UL 10C listings. Current NFPA 80 requirements reference UL 10C.

The Five Standard Fire Door Ratings: Hardware Requirements at Each Level

20 Min

Corridor Doors in Sprinklered Buildings and Apartment Entry Doors

Where 20-minute doors are required

Twenty-minute rated doors are required in corridor walls with 1-hour fire resistance ratings in most sprinklered commercial occupancies. They are also required for apartment entry doors in R-1 and R-2 occupancies (hotels, apartment buildings, dormitories) in many jurisdictions, and at openings in 1-hour fire-separation walls including some elevator lobby enclosures and low-hazard occupancy separations.

Door construction options at 20 minutes

Both hollow metal and wood doors can achieve the 20-minute rating. Wood 20-minute doors can use standard particleboard core or mineral core construction. This is the only rating where standard wood core doors are permitted. All higher ratings require mineral core wood or hollow metal construction.

Required hardware at 20 minutes

Self-closing device: surface closer, concealed closer, floor closer, or spring hinges. Spring hinges are permitted only at the 20-minute level and are not acceptable substitutes for closers at higher ratings.
Positive-latching lockset: cylindrical, mortise, or exit device that automatically latches on door closure. Passage function (non-latching) hardware is not permitted.
Fire-listed steel hinges: minimum three hinges for doors up to 90 inches in height.
If occupant load requires an exit device: fire exit hardware (UL 305 plus UL 10C). Standard panic hardware (UL 305 only) is not compliant on a fire-rated door.

45 Min

The Most Frequently Specified Rating in Commercial Construction

Where 45-minute doors are required

Forty-five minute doors are required in 1-hour rated corridor walls in non-sprinklered commercial occupancies and in many 1-hour rated occupancy separations. In New York City and many metropolitan jurisdictions, the 45-minute rating is the most common specification for apartment entry doors in R-1 and R-2 occupancies. Exit stairwell doors in buildings with 1.5-hour rated enclosures also typically require 45-minute doors.

Door construction at 45 minutes

Hollow metal doors can achieve the 45-minute rating. Wood doors at 45 minutes require mineral core construction. Drywall frames can support 45-minute assemblies; standard hollow metal drywall frames are suitable. Spring hinges are not permitted at this rating: a listed door closer is required.

Required hardware at 45 minutes

Listed door closer (not spring hinges). The closer must be sized to fully close and latch the door from any open position.
Positive-latching lockset with fire listing for 45-minute rating.
Fire-listed steel hinges, minimum three hinges.
Fire exit hardware (UL 305 plus UL 10C) if occupant load requires an exit device. Mechanical dogging is prohibited.

The 45-minute Schlage L Series mortise lock specification detail most locksmiths miss: The Schlage L Series mortise lock is available in both fire-rated and non-fire-rated versions. The fire-rated version carries a UL fire listing label on the lock case. When replacing an L Series mortise lock on a 45-minute or higher fire door, the replacement must be the fire-rated version of the same function, not the standard (non-fire-rated) version even though they appear physically identical. The UL label on the lock case is the only external indicator of fire-rated status on an installed L Series mortise lock. Browse fire-listed Schlage L Series mortise lock parts at Security Parts.

60 Min

Exit Stairwells in Lower-Rise Buildings and Certain Occupancy Separations

Where 60-minute doors are required

Sixty-minute doors are required in 1.5-hour rated wall assemblies, in exit stairwell enclosures serving buildings of approximately four stories or fewer, and in certain occupancy separations where the applicable code table specifies a 1-hour door (which maps to the 60-minute assembly rating). This rating is more common in commercial and institutional buildings than in residential construction.

Door construction at 60 minutes

Hollow metal doors achieve the 60-minute rating in 16-gauge or 18-gauge galvanneal steel with honeycomb or mineral core construction. Wood doors at 60 minutes require mineral core construction. Both drywall and masonry frames support 60-minute assemblies. Intumescent seals at the door perimeter may be required depending on the assembly listing and whether smoke control is also required.

Required hardware at 60 minutes

Listed door closer sized appropriately for door weight and width.
Fire-listed positive-latching lockset (cylindrical or mortise with fire listing at 60-minute level).
Fire-listed steel hinges, minimum three.
Fire exit hardware (UL 305 plus UL 10C) if occupant load requires an exit device.
Smoke seal gaskets if the assembly carries an S (smoke) designation.

90 Min

Exit Stairwells in Mid-Rise and High-Rise Buildings and 2-Hour Wall Openings

Where 90-minute doors are required

Ninety-minute doors are required in 2-hour rated wall assemblies, in exit stairwell enclosures in mid-rise and high-rise buildings, and in major occupancy separations where 2-hour wall ratings are specified. This is the most demanding rating achievable with drywall frames and wood door construction. Any opening requiring higher than 90 minutes must use masonry frames and hollow metal doors.

Door construction at 90 minutes

This is the maximum rating achievable with wood mineral core construction and drywall frames. Hollow metal doors achieve the 90-minute rating readily. Vision panels (glazing) in 90-minute doors are limited to 100 square inches maximum with a maximum dimension of 10 inches using fire-protective glazing under NFPA 80. Fire-resistive glazing may permit larger panels depending on the specific tested assembly listing.

Required hardware at 90 minutes

Listed door closer. Spring hinges are not permitted at any rating above 20 minutes.
Fire-listed positive-latching lockset with 90-minute listing.
Fire-listed steel hinges. Ball-bearing steel hinges with fire listing are standard.
Fire exit hardware (UL 305 plus UL 10C) if occupant load requires an exit device. Von Duprin 98 and 99 series with fire listing are the standard specification for 90-minute stairwell and fire corridor doors. Browse Von Duprin fire exit hardware parts.
Smoke seals if the assembly requires S designation.
Coordinator if this is a pair of doors requiring sequenced latching.

The coordinator requirement on pairs of 90-minute doors that most projects miss: When a fire-rated opening uses a pair of doors (double doors meeting in the center), the door that latches first must be the inactive leaf, and the active leaf (the one with the closer-side latch) must close against the already-latched inactive leaf to engage its latch. Without a coordinator device that controls the closing sequence, both leaves often reach the closed position simultaneously, preventing either from latching correctly. The coordinator connects the two door closers to ensure the inactive leaf always closes and latches before the active leaf. On 90-minute pair openings without coordinators, the NFPA 80 annual inspection will cite the pair as non-compliant because positive latching cannot be confirmed.

3 Hour / 180 Min

Building Separations, Major Fire Areas, and 4-Hour Wall Openings

Where 3-hour doors are required

Three-hour doors are required at openings in 4-hour rated firewalls separating buildings or large fire areas, in building separation walls, and in certain hazardous occupancy separations where the code requires the maximum available door protection. This is the highest rating available for swinging door assemblies. Three-hour rated doors are specified in applications where the fire scenario is an extended, severe fire with significant property and life safety consequences beyond what shorter-rated assemblies can contain.

Door construction at 3 hours

Three-hour ratings require hollow metal (steel) construction. Wood doors cannot achieve 3-hour ratings. Masonry frames are required: drywall frames cannot support the 3-hour rating. Vision panels (glazing) are generally not permitted in 3-hour doors. Where required by a specific tested assembly listing, only fire-resistive glazing in very limited dimensions is acceptable. This is the most restrictive rating for glazing.

Required hardware at 3 hours

Listed door closer with UL fire listing at 3-hour level. Not all closers carry 3-hour listings. Confirm the LCN closer model's specific fire listing duration before specifying.
Fire-listed positive-latching lockset at 3-hour rating level.
Fire-listed steel hinges rated to 3 hours.
Fire exit hardware (UL 305 plus UL 10C at 3-hour level) if occupant load requires an exit device.

Panic Hardware vs Fire Exit Hardware: The Critical Distinction

This is the most consequential specification error in commercial exit device selection. Installing panic-only hardware on a fire-rated door is a code violation that creates a non-compliant fire assembly. The visual difference between the two types is not obvious, but the compliance implications are significant.

Panic Hardware (UL 305 Only)

Listed under UL 305 (Panic Hardware)

Used on non-fire-rated doors only

Mechanical dogging permitted: latch can be held retracted with a hex key for push-pull operation

Carries one label: UL 305 panic label

Has NOT been tested under positive pressure fire conditions

Maximum unlatching force: 15 lbf (67 N)

Required where occupant load meets IBC/NFPA 101 threshold on non-fire openings

Fire Exit Hardware (UL 305 + UL 10C)

Listed under both UL 305 and UL 10C (positive pressure fire test)

Required on fire-rated doors where exit device is needed

Mechanical dogging PROHIBITED: fire door must positively latch on every closure

Carries two labels: UL 305 panic label AND UL 10C fire label

Has been tested under positive pressure fire conditions for rated duration

Maximum unlatching force: 15 lbf (67 N) (same as panic hardware)

Required where occupant load meets threshold AND door is fire-rated

How to Identify Fire Exit Hardware vs Panic Hardware in the Field

On installed exit devices, the UL label on the device mechanism case identifies the listing type. Fire exit hardware carries two separate UL labels on the mechanism case: one indicating the panic listing (UL 305) and one indicating the fire listing (UL 10C) with the specific fire rating in minutes. Panic-only hardware carries only the UL 305 label with no fire rating label. If the mechanism case label does not include a fire rating in minutes alongside the panic listing, the device is panic hardware only and is not compliant on a fire-rated door.

Von Duprin exit devices in the 98 and 99 series are available in both panic-only and fire-rated versions. The fire-rated version of the 98/99 does not have a mechanical dogging function (the dogging socket opening is plugged). Browse Von Duprin fire exit hardware parts by series at Security Parts.

Electric Dogging: The Compliant Push-Pull Solution for Fire Doors

Many buildings want push-pull operation during business hours on fire-rated corridor doors to reduce closer wear and improve traffic flow. Mechanical dogging (using a hex key to hold the latch retracted) is prohibited on fire exit hardware. The compliant solution is electric dogging.

Electric dogging holds the push bar in the actuated (latch-retracted) position through an electromagnetic mechanism powered by a low-voltage electrical connection. The building wiring connects the electric dogging mechanism to the fire alarm panel. During normal operations, the electric dogging mechanism holds the latch retracted. When the fire alarm activates, current interruption causes the electromagnetic mechanism to release the push bar, allowing the latch spring to drive the latch bolt to the extended (latched) position. The door then operates as full fire exit hardware.

Von Duprin electric latch retraction (EL) devices provide this function on 98/99, 22, 33A/35A, and related series. Von Duprin's QEL (Quiet Electric Latch retraction) provides the same function with reduced operating noise. These are the Von Duprin series covered in the electric strikes and electrified hardware catalog and the Von Duprin exit device parts catalog at Security Parts.

The S Label: Smoke Control Assembly Requirements

A fire door assembly rated for fire protection (20, 45, 60, 90, or 180 minutes) provides resistance to flames and heat for the rated duration. It does not necessarily provide resistance to smoke passage at ambient temperatures. In areas where smoke control is required (smoke barriers in healthcare, smoke compartments, pressurized exit stairwells), the door assembly must carry an S designation in addition to its fire rating.

The S label is applied to assemblies that have been tested for smoke leakage resistance at the elevated pressure differential created by smoke control systems. S-rated assemblies require smoke seal gaskets around the door perimeter (typically at the head and latch edge, and sometimes at the threshold). The gasket material may be intumescent (expanding under heat to seal the gap) or compression type (sealing through mechanical compression against the door and frame surfaces).

When replacing hardware or seals on an S-labeled fire door, the smoke seal gaskets must also be replaced and confirmed intact. A missing or damaged smoke seal gasket on an S-rated assembly creates a non-compliant smoke barrier, which NFPA 80 annual inspectors specifically check for in healthcare and high-rise occupancies.

Fire-Listed Hardware from SecurityParts.com by Component Type

Component	OEM Fire-Listed Option	Ratings Available	Browse
Exit devices (fire exit hardware)	Von Duprin 98/99 series (F suffix indicates fire listing)	Up to 3-hour UL 10C	Exit Device Parts
Rim exit devices (fire)	Von Duprin 22 series fire-listed version	20-minute through 90-minute	Von Duprin Parts
Door closers	LCN 4040XP series with UL fire listing	3-hour UL 10C rated	Door Closer Parts
Concealed closers	LCN 2010/5010 series fire-listed versions	Confirm listing by model	LCN Parts
Cylindrical locks	Schlage ND Series fire-listed functions	20 through 90 minute	Cylindrical Lock Parts
Mortise locks	Schlage L Series fire-listed functions	Up to 3-hour	Mortise Lock Parts
Interconnected locks	Schlage CS210 (UL-listed for 3-hour fire door)	3-hour UL listed	Interconnected Lock Parts
Deadbolts	Schlage B500 Series fire-rated versions	Fire-rated with dustbox	Deadbolt Parts

Pre-order fire-listing verification and compatibility support at 845-935-0301 or the contact page. For the full Allegion fire-listed hardware catalog, browse the all products and parts catalog.

Why Choose Security Parts for Fire Door Hardware Parts

UL 10C positive pressure explained, coordinator requirement documented, 45-minute L Series fire listing detail, smoke S label compliance, and same-day OEM shipping.

Positive Pressure Explanation

We document why UL 10C positive pressure testing replaced UL 10B and what the difference means for real fire performance. Hardware listed under UL 10B only may not resist fire-driven outward pressure that UL 10C-listed hardware has been proven to withstand.

Coordinator Pair Door Requirement

We document that 90-minute and higher rated pairs of doors require coordinators for correct latching sequence. This requirement is missed in most projects and cited in nearly every NFPA 80 annual inspection of paired fire doors without coordinators.

Fire Listing on L Series Locks

We document that Schlage L Series mortise locks are available in fire-rated and non-fire-rated versions that appear physically identical. The fire rating label on the lock case is the only field-visible indicator. Replacing with the non-fire-rated version voids the assembly listing.

Same-Day OEM Shipping

Fire-listed OEM parts from Von Duprin, LCN, Schlage, and Falcon ship same day from US warehouses. Call 845-935-0301 or use the contact page for fire listing verification support.

What Makes Security Parts Different for Fire Door Hardware

We document the UL 10C positive pressure vs UL 10B neutral pressure distinction and explain the real-world performance difference. Hardware tested under neutral pressure conditions may not resist fire-driven outward pressure that occurs in actual fires. This fact is absent from all competitor parts supplier content.
We document the paired door coordinator requirement for 90-minute and higher ratings. This is cited in NFPA 80 annual inspections on virtually every paired fire door opening without a coordinator, yet is never documented in standard hardware specification content at the parts ordering stage.
We document the Schlage L Series fire rating label identification issue: fire-rated and non-fire-rated L Series mortise locks are visually identical; only the lock case label distinguishes them. Ordering the wrong version voids the fire assembly listing with no visible indication at installation.
We document the wood door construction limitation at each rating level: 20-minute only with standard core, 45 to 90 minute require mineral core, and beyond 90 minutes require hollow metal. This prevents the specification error of ordering a wood door replacement for an opening that requires mineral core or hollow metal construction.
We carry UL fire-listed OEM parts for Von Duprin fire exit hardware, LCN fire-rated door closers, Schlage fire-listed cylindrical locks, and fire-listed mortise locks for complete fire door assembly compliance in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Frequently Asked Questions About Commercial Door Fire Ratings

What is the relationship between a wall's fire resistance rating and the required door fire rating?

Door assemblies are typically rated at approximately 75 percent or less of the wall's fire resistance rating. A 1-hour wall requires a 45-minute door, a 2-hour wall requires a 90-minute door, and a 4-hour wall requires a 3-hour door. The ratio exists because door assemblies are tested differently from wall assemblies under different test standards and cannot match wall rating durations. The IBC and NFPA 80 specify the exact required ratings by wall type and occupancy. The AHJ may require higher ratings than the code minimum.

What is the difference between panic hardware (UL 305) and fire exit hardware (UL 305 plus UL 10C)?

Panic hardware (UL 305) is for non-fire-rated doors. It allows mechanical dogging to hold the latch retracted for push-pull operation. Fire exit hardware carries both UL 305 and UL 10C listings and is required on fire-rated doors where an exit device is needed. Fire exit hardware prohibits mechanical dogging because fire-rated doors must positively latch on every closure. Electric dogging connected to the fire alarm panel is the compliant push-pull solution for fire-rated doors. Installing UL 305 panic-only hardware on a fire-rated door is a life-safety code violation.

What hardware is required on all fire-rated door assemblies regardless of rating?

Three hardware elements are required on all fire-rated doors regardless of rating: a self-closing device (surface closer, concealed closer, or floor closer at 45 minutes and above; spring hinges permitted only at 20 minutes), a positive-latching lock or latch that automatically engages the strike on every closure, and fire-listed steel hinges (minimum three for doors up to 90 inches in height). Passage function (non-latching) hardware is prohibited. Every component must carry a fire listing matching or exceeding the door's rating.

What is UL 10C positive pressure testing and why does it replace the older neutral pressure test?

UL 10C tests door assemblies under positive pressure from the fire side, simulating the outward air pressure generated by combustion gases in a real fire. The older UL 10B test used neutral (atmospheric) pressure, which did not simulate fire-driven outward pressure. Hardware that passed UL 10B may not resist the actual positive pressure of a fire event. UL 10C became the standard in the late 1990s and is the current NFPA 80 referenced standard. All current fire door hardware should carry UL 10C listings.

Can a wood door be used for a 90-minute fire rating?

Yes, with mineral core construction only. Wood doors with standard particleboard core are limited to 20-minute ratings. Wood doors with mineral core (mineral bonded crossband and matching edge) can achieve 20, 45, 60, and 90-minute ratings. Wood doors cannot exceed 90 minutes: 3-hour ratings require hollow metal (steel) construction. The 90-minute rating is also the maximum for drywall frames: 3-hour ratings require masonry frames.

What is the S label on a fire door and when is smoke control assembly required?

The S label indicates a fire door assembly that has been tested for smoke leakage resistance in addition to its fire rating. S-rated assemblies are required at smoke barriers in healthcare occupancies, smoke compartments, and pressurized stairwells where smoke control is specified in addition to fire separation. S-labeled assemblies require smoke seal gaskets at the door perimeter. A missing or damaged smoke seal on an S-rated door creates a non-compliant smoke barrier. NFPA 80 annual inspectors specifically verify smoke seal integrity on S-labeled assemblies in healthcare facilities during CMS surveys.

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Electric Strike Schematic Diagram: How to Wire a Commercial Electric Strike to Any Access Control System Tuesday, July 21, 2026

An electric strike schematic diagram shows the complete circuit path from the power supply through the access control panel to the strike solenoid at the door frame. Reading and understanding this diagram before touching a single terminal is the difference between a clean installation and a burned solenoid, a damaged access panel, or a door that fails at the worst possible moment. This guide covers the full electric strike schematic diagram for both fail safe and fail secure configurations, including REX switch placement, door position switch monitoring, back EMF protection, AC-to-DC rectifier conversion, and Von Duprin series-specific wiring for the 5100, 6100, 6200, and 6300 product lines.

Use this electric strike schematic diagram guide to wire any commercial electric strike installation correctly the first time. SecurityParts.com stocks Von Duprin electric strike parts and replacement components for the complete range of commercial electric strike configurations. Browse Von Duprin electric strike parts and diagrams by series, read the electric strike components and failure guide, or compare configurations in the Schlage L9580 vs electric strike comparison. Call 845-935-0301 or visit the SecurityParts.com contact page for pre-order wiring and specification support.

The Electric Strike Schematic Diagram: The Three-Element Circuit

Every electric strike schematic diagram, regardless of brand, voltage, or fail-mode configuration, is built on the same three-element series circuit. Understanding these three elements before looking at any specific diagram prevents the most common wiring mistakes.

The three elements are the power supply, the access control panel output relay (which acts as the switch in the circuit), and the electric strike solenoid. Current flows from the power supply, through the relay, to the strike solenoid, and back to the power supply. Nothing unlocks unless all three elements are correctly wired, powered, and functioning at the same time.

The Fail Secure Schematic Diagram (Normally Open Circuit)

In a fail secure configuration, the circuit between the power supply and the strike solenoid is normally open. No current flows to the solenoid under normal locked conditions. When an authorized credential is presented at the reader, the access panel closes its output relay for a programmed duration, typically 3 to 10 seconds, completing the circuit and energizing the solenoid to release the keeper. When the relay opens again, power stops, the solenoid de-energizes, and the keeper spring-returns to the locked position.

Fail Secure (Power-to-Unlock) Schematic

DC Power Supply
12VDC or 24VDC

Access Panel
Output Relay (NO)

Electric Strike
Solenoid

Suppression
Diode

Relay normally open. Power flows only during access grant. Strike locked on power loss. Required for fire-rated doors.

With REX Switch Added (Parallel to Relay)

DC Power Supply

Panel Relay (NO)
OR REX Switch (NO)

Electric Strike
Solenoid

REX wired in parallel with relay. Either device completes circuit independently. Most common commercial configuration.

The Fail Safe Schematic Diagram (Normally Closed Circuit)

In a fail safe configuration, the circuit is normally closed. Current flows to the solenoid continuously during normal operation, keeping the keeper engaged in the locked position. When an access grant occurs, the access panel opens its relay, breaking the circuit, de-energizing the solenoid, and allowing the keeper to release. The door can then be pushed open without retracting the latchbolt. When the door closes again and the relay closes, current resumes and the strike re-locks.

Fail Safe (Power-to-Lock) Schematic

DC Power Supply
DC Required (not AC)

Access Panel
Output Relay (NC)

Electric Strike
Solenoid (continuous)

Relay normally closed. Power flows continuously. Strike unlocks when relay opens. Non-fire-rated doors only per NFPA 80.

Fail safe strikes cannot be installed on fire-rated door assemblies. NFPA 80 and UL 10C certification both prohibit fail safe electric strikes on fire-rated openings. A power failure during a fire event would de-energize the solenoid, release the keeper, and allow the fire door to open. This is the exact opposite of what a fire door is required to do. If you are unsure whether a door is fire-rated, check the UL label on the hinge edge of the door before selecting strike configuration. Always confirm the fail mode with your building's authority having jurisdiction before installing.

Wire Gauge, Run Length, and Voltage Drop

Minimum Wire Gauge Requirements

Wiring methods for electric strikes must comply with ANSI/NFPA 70, the National Electrical Code. The minimum permissible wire size is 26 AWG based on published manufacturer installation guidelines, but this minimum is suitable only for very short runs in protected indoor locations. Commercial installations should use heavier gauge wire in nearly every case.

Minimum by code

26 AWG

Short runs under 25 feet, indoor only

Standard commercial

22 AWG

Up to 75 feet on 12VDC systems

Long runs

18 AWG

75 to 200 feet or where voltage drop is a concern

High-traffic or monitored

18 AWG shielded

Where monitoring contacts are included in the same run

How Voltage Drop Affects Strike Performance

Voltage drop occurs because resistance in the wire reduces the voltage delivered to the solenoid at the end of the run. The longer the wire run and the thinner the gauge, the more voltage is lost before it reaches the strike. A solenoid that receives more than 10 percent below its rated voltage will actuate sluggishly or fail to release the keeper entirely.

A practical example: a 12VDC solenoid rated at 10 percent tolerance requires a minimum of 10.8 volts at the terminals. On a 22 AWG wire with a 100-foot round-trip run (50 feet each way), voltage drop is approximately 1.5 volts, leaving 10.5 volts at the strike. This is within tolerance. On a 150-foot round-trip run with the same wire gauge, voltage drop reaches approximately 2.2 volts, leaving 9.8 volts, which is below the 10.8-volt minimum. Use 18 AWG for that run instead.

Always measure round-trip wire length, not one-way distance. Current travels to the solenoid through the positive wire and returns through the negative wire. Both legs contribute to the total resistance of the circuit. A 75-foot run from the power supply to the door has a 150-foot total round-trip wire length for voltage drop calculation purposes.

Back EMF Protection: The Diode That Protects Your Access Panel

What Back EMF Is and Why It Matters

When a solenoid coil is de-energized, either because the relay opens (fail secure) or because a power failure occurs, the magnetic field inside the coil collapses instantly. This collapse induces a reverse voltage spike in the wiring, sometimes called back EMF (electromotive force). This spike can exceed several times the normal operating voltage for a fraction of a second and travels back through the wiring toward the access control panel's output relay.

Modern access control panels have solid-state output transistors that are sensitive to reverse voltage spikes. A single large spike or repeated smaller spikes can degrade or destroy the transistor, causing the panel's lock output to stop functioning while everything else on the panel continues to work normally. The failure looks like a wiring problem or a failed relay when the actual cause is cumulative back EMF damage from months of normal solenoid cycling.

How to Wire the Suppression Diode

A standard 1N4001 diode (or equivalent rated for at least 50V and 1A) wired in parallel across the solenoid terminals provides back EMF suppression. The diode is installed with its cathode (the banded end) toward the positive terminal of the strike and its anode toward the negative terminal. Under normal operation the diode is reverse-biased and carries no current. When the solenoid de-energizes and the reverse voltage spike occurs, the diode becomes forward-biased, creating a low-resistance path that absorbs and dissipates the spike before it reaches the access panel.

Back EMF Diode Placement in Schematic

Power Supply (+)

Panel Relay

Strike Solenoid (+) to (-)

Diode across solenoid terminals
Cathode (banded) at + terminal
Anode at - terminal

Diode is wired in parallel with solenoid, not in series. Does not affect normal operation. Clamps reverse spike on de-energization.

Some access control panels include built-in back EMF suppression on their lock output terminals. Check your access panel's installation manual before adding an external diode. If the panel already includes a built-in TVS diode or snubber circuit on the lock output, adding an external diode is redundant but harmless. If the panel does not specify built-in suppression, always add the external diode at the strike terminals.

REX Switch and Door Position Switch Wiring

REX (Request to Exit) Switch Placement

A REX (Request to Exit) switch allows a person exiting the building through an access-controlled door to release the electric strike without credential verification. Pressing the REX button momentarily unlocks the strike from the inside, allowing egress without requiring a card, PIN, or key fob. This is required on most commercial access-controlled doors to prevent occupants from being trapped if the access control system fails.

In the schematic diagram, the REX switch connects in parallel with the access control panel's output relay. This wiring allows either the panel relay or the REX switch to independently complete the circuit and energize the solenoid. On fail secure systems the REX is a normally-open momentary contact switch. Pressing it closes the circuit, sends power to the solenoid, and releases the keeper for as long as the button is held or for a timed duration depending on the panel configuration.

Door Position Switch (DPS) Wiring

A door position switch monitors whether the door is physically open or closed and reports this status to the access control panel separately from the strike status. The DPS is a magnetic contact switch mounted in the door frame with a magnet on the door leaf. When the door is closed, the magnet keeps the switch in its resting state. When the door opens, the magnet moves away and the switch changes state, sending a signal back to the panel.

The DPS wiring runs on a completely separate circuit from the strike power wiring. It typically connects to a dedicated input terminal on the access control panel labeled "DI" (door input) or "DS" (door sensor). Mixing the DPS monitoring wiring with the strike power wiring is one of the most common installation errors and produces phantom door-open alarms that take significant time to diagnose.

Dual Switch (DS) Monitoring on Von Duprin Strikes

Von Duprin 6200 Series strikes with the DS (dual switch) option include two internal SPDT monitoring switches inside the strike body rather than requiring a separate external door position switch for basic strike status monitoring. One switch monitors the latchbolt tripper position (whether a latch bolt is seated in the strike pocket). The other switch monitors the keeper position (whether the keeper is fully returned to the locked position after a release cycle).

In the electric strike schematic diagram for a DS-equipped unit, the monitoring switch wires run back to the access panel's monitoring input terminals on a separate low-voltage circuit. The DS option produces two independent status signals that most modern access panels can display separately, allowing the panel to distinguish between a door that is closed-and-latched versus a door that is closed-but-not-fully-latched, a critical distinction on high-security openings. Browse Von Duprin electric strike parts including DS monitoring components at SecurityParts.com.

AC Power and the SO12/SO24 Rectifier Kit

Why Electric Strikes Require DC Power

Electric strike solenoids are designed for DC (direct current) power. The solenoid coil generates a sustained magnetic field that holds the plunger in position, and this requires the consistent unidirectional current flow that DC provides. AC (alternating current) reverses polarity 60 times per second in a standard US electrical circuit. This reversal causes the solenoid plunger to try to move in both directions 60 times per second, producing a buzzing vibration, generating significant heat, and causing accelerated solenoid wear or immediate failure.

If your electric strike buzzes after installation, AC power is almost always the cause. Check that your power supply output is labeled DC, not AC. Many low-cost power supplies output AC even though the label says "power supply." Measure the output with a multimeter set to DC volts. If you read voltage but the strike still buzzes, switch to the AC setting on the meter. A reading on AC confirms that AC power is reaching the strike. Do not continue operating the strike in this condition. Replace the power supply or add an inline rectifier.

The Von Duprin SO12 and SO24 Rectifier Kits

Von Duprin SO12 and SO24 rectifier kits are inline AC-to-DC conversion modules designed specifically for Von Duprin 6200 Series electric strike applications where only AC power is available from the building's low-voltage transformer. The SO12 converts AC input to 12VDC output. The SO24 converts AC input to 24VDC output. Both install inline between the AC power source and the strike terminals without any modification to the strike body or the frame.

In the schematic diagram, the rectifier kit appears between the AC power supply and the access control panel relay. The AC feeds into the rectifier, the rectifier outputs DC, and the DC then flows through the relay to the strike solenoid. The rectifier kit does not eliminate the need for a suppression diode if the access panel requires back EMF protection.

AC Source with SO12/SO24 Rectifier Kit

AC Power Source

SO12 or SO24
Rectifier Kit

Panel Relay

Electric Strike
Solenoid (DC)

Rectifier converts AC to DC before reaching relay and strike. Strike receives correct DC power. Buzzing eliminated.

Terminal Block Connections: Step-by-Step Wiring Sequence

Identifying the Terminal Block

The electric strike terminal block is the connection point between the building wiring and the strike solenoid. On most Von Duprin commercial strikes, the terminal block is a small plastic block with two to six screw terminals inside the strike housing, accessible through a cover plate or directly from the frame side of the installation. Terminal labels vary by series. Most units mark terminals as COM (common), NO (normally open), or NC (normally closed) for relay output configurations, and as plus (+) and minus (-) for direct solenoid power connections.

On Von Duprin 6200 Series strikes with the DS monitoring option, the terminal block also includes two pairs of monitoring switch terminals in addition to the solenoid power terminals. These are physically separate from the power terminals and must be wired to separate input terminals on the access panel. Connecting the monitoring switch terminals to the power terminals will damage both the switch and the panel input.

Step-by-Step Terminal Connection Sequence

Verify power supply output voltage and type before any connections Use a multimeter to confirm the power supply outputs DC at the rated voltage (12VDC or 24VDC). Verify the no-load voltage does not exceed the solenoid rating by more than 10 percent. Many unregulated power supplies output significantly higher voltage under no-load conditions. A 12VDC rated supply may measure 14 to 15 volts without a connected load. Install a regulated power supply on any installation where voltage accuracy matters.
Cut power before making any terminal connections All connections to the terminal block must be made with the power supply disconnected. Making live connections risks a short circuit across the solenoid terminals, an immediate solenoid burn, or panel output relay damage. Confirm power is off with the multimeter before inserting any wires into the terminal block.
Connect the positive wire from the power supply to the positive (+) terminal The positive lead from the power supply runs through the access panel output relay before reaching the strike. Confirm the relay output terminal on the access panel and connect the wire from the normally-open (NO) terminal of the relay to the positive terminal of the strike. The incoming positive lead from the power supply connects to the COM terminal of the relay.
Connect the negative wire directly from power supply to strike negative terminal The negative (return) wire runs directly from the power supply negative terminal to the strike's negative terminal, bypassing the relay. The relay switches only the positive side of the circuit in standard commercial wiring.
Wire the REX switch in parallel with the access panel relay output Connect one terminal of the REX switch to the same wire junction as the relay's NO terminal and positive supply line. Connect the other REX terminal to the positive terminal of the strike. Pressing the REX switch now completes the circuit to the strike independently of the panel relay.
Install the back EMF diode across the strike terminals With power still off, connect a 1N4001 diode across the positive and negative terminals of the strike. Cathode (banded end) connects to the positive terminal. Anode connects to the negative terminal. The diode goes in parallel with the solenoid, not in series.
Connect door position switch or DS monitoring wires to separate panel input terminals If the strike includes DS monitoring or a separate door position switch is installed, run the monitoring wires to the dedicated input terminals on the access control panel. Do not combine these low-current monitoring wires in the same terminal as the solenoid power wires.
Restore power and test each function independently Apply power and use the access panel's test function to send an access grant signal. Confirm the keeper releases and returns. Test the REX switch independently. Confirm the DS monitoring reads correctly on the panel status display. Test the door position switch by opening and closing the door while watching the panel status indicator.

Von Duprin Series Wiring Differences

Von Duprin electric strikes across the 5100, 6100, 6200, and 6300 product lines share the same basic schematic diagram but have series-specific differences in terminal configuration, voltage options, and monitoring capabilities that affect the wiring before the installation begins.

5100 Series

Voltage: 12VDC or 24VDC (specify at order)

Monitoring: No internal monitoring switch

Terminals: Two-terminal solenoid power only

Notes: Cylindrical and mortise compatible. Solenoid not field-replaceable.

6100 Series

Voltage: 12VDC or 24VDC (specify at order)

Monitoring: No internal DS switch

Terminals: Two-terminal solenoid power only

Notes: Heavy-duty rim exit device applications. Solenoid not field-replaceable.

6200 Series

Voltage: 24VDC standard (12VDC and AC with SO kits)

Monitoring: Optional DS dual switch (two SPDT contacts)

Terminals: Power terminals plus optional DS monitoring terminals

Notes: External solenoid canister replaces in under 5 minutes. SO12/SO24 rectifier kits available for AC sources. Most versatile series for commercial retrofit.

6300 Series

Voltage: 24VDC standard

Monitoring: DS dual switch standard

Terminals: Power terminals plus dual switch monitoring terminals

Notes: Heavy-duty stainless steel for high-security and exterior applications. Monitoring is standard, not optional. Same SO rectifier kit compatibility as 6200 for AC applications.

Browse Von Duprin electric strike series parts and diagrams at SecurityParts.com. For parts specific to each series, the interactive parts diagram on each model page shows every terminal, component, and part number specific to that product.

Common Wiring Mistakes and How to Avoid Them

Sharing the Access Panel Power Supply with the Electric Strike

Most access control panels include a low-current internal power supply designed for the panel board and credential verification components. This internal supply is not designed to also power the solenoid. An electric strike solenoid draws 300mA to 500mA on activation, which can cause the panel's internal supply to sag, resetting the panel firmware or causing erratic relay behavior. Always power the electric strike from a dedicated, appropriately rated power supply that is separate from the panel's internal supply.

Running AC Power to a DC-Rated Solenoid Without a Rectifier

This is the single most common installation error in commercial electric strike work. The buzzing sound it produces is unmistakable and the solenoid damage it causes is rapid. If AC is the only power source available, install an SO12 or SO24 rectifier kit in-line before the strike terminals. If a Von Duprin rectifier kit is not the right fit for the installation, a standard full-wave bridge rectifier module with appropriate voltage and current ratings performs the same function.

Reversing the Back EMF Diode Polarity

A diode installed with reversed polarity (anode at positive terminal, cathode at negative) becomes a short circuit when the solenoid energizes. This blows the access panel's output fuse or destroys the output transistor within the first access grant. Always orient the diode with the cathode banded end toward the positive terminal. If uncertain, test the installation with a multimeter set to diode mode before powering the circuit.

Connecting Monitoring Switch Wires to Power Terminals

DS monitoring switches inside the strike operate at the low-current levels used by the access panel's input circuit, typically milliampere-level signals. The solenoid power terminals carry hundreds of milliamperes. Connecting the monitoring wires to the power terminals sends full solenoid current through the monitoring switch, burning the switch immediately and potentially damaging the access panel's input circuit. Always identify monitoring terminals separately from power terminals before making any connections.

Using Undersized Wire on Long Runs

An installation that tests correctly at 50 feet of wire and then fails intermittently at 150 feet is almost always a voltage drop problem caused by undersized wire gauge. The solenoid actuates on the bench, actuates correctly during initial commissioning, and then begins to fail intermittently as the solenoid winding heats up and its resistance increases slightly. Calculate voltage drop before selecting wire gauge. Use 18 AWG for runs over 75 feet on 12VDC systems.

Why Choose SecurityParts.com for Von Duprin Electric Strike Parts

SecurityParts.com has supplied commercial door hardware parts since 2001. Our Von Duprin electric strike catalog covers the complete 5100, 6100, 6200, and 6300 Series with model-specific interactive parts diagrams on every product page. The interactive diagram lets you visually confirm the exact solenoid, keeper, monitoring switch, faceplate, or rectifier kit before placing the order, eliminating most wrong-part returns before they happen.

The Von Duprin 6200 Series solenoid canister is externally mounted and replaces in under five minutes without removing the strike from the frame. This is the repair that saves hours on high-traffic commercial openings where full unit removal and frame patching is the only alternative on many legacy installations. SecurityParts.com stocks solenoid canisters, SO12 and SO24 rectifier kits, DS monitoring switch components, keepers, and faceplates for the complete Von Duprin electric strike range.

Browse Von Duprin electric strike parts and diagrams by series, read the electric strike components and failure diagnosis guide, browse the complete Von Duprin parts catalog, or see all SecurityParts.com commercial door hardware parts. Call 845-935-0301 or visit the SecurityParts.com contact page for pre-order wiring and specification support.

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Schlage Deadbolt Diagram: Every Component Labeled and Explained Monday, July 20, 2026

When a Schlage deadbolt stops working correctly, the fastest path to the right replacement part is knowing what each component in the diagram is named, what it does, and where to find it. This guide walks through every labeled component in a Schlage deadbolt diagram, starting from the key cylinder on the outside and ending at the strike box in the frame. It applies to the full Schlage B Series including the B60N, B62N, B500, and B600 models.

SecurityParts.com stocks OEM Schlage deadbolt parts for the complete B Series range. Browse Schlage deadbolt replacement parts by model, the Schlage B Series deadbolt parts guide, and the Schlage strike plates and latch bolt parts guide. Call 845-935-0301 or visit the SecurityParts.com contact page for same-day parts identification support.

How to Read a Schlage Deadbolt Diagram

A Schlage deadbolt parts diagram shows the lock in an exploded view, with each component pulled apart from the others and numbered or labeled. The exploded view reveals how components nest together when assembled. The two sides of the diagram represent the outside of the door (the key cylinder side) and the inside of the door (the thumb turn side), connected through the door by the housing and the bolt assembly.

The strike assembly shown in the diagram is separate from the lock body and mounts into the door frame rather than the door itself. When ordering replacement parts, components from the door-side diagram are different products from the strike-side components, so identifying which side the failed part belongs to is always the first step.

The Outside Components: Key Cylinder Side

1. The Key Cylinder (Cylinder Plug and Shell)

The cylinder is the outermost component in the Schlage deadbolt diagram on the exterior side of the door. It consists of two main parts shown in the diagram: the cylinder plug (the rotating inner section that the key engages) and the cylinder shell (the outer housing that does not rotate). Inside the plug, the diagram shows a series of pin chambers running perpendicular to the plug face. Each chamber holds a key pin at the bottom and a driver pin above it, separated by the shear line when the correct key is inserted.

In a Schlage B Series single-cylinder deadbolt (B60N, B500, B600), there is one cylinder on the exterior side only. In a double-cylinder deadbolt (B62N, B502, B602), the diagram shows a cylinder on both the exterior and interior sides, replacing the thumb turn shown on single-cylinder models.

2. The Tailpiece (Cylinder Tailpiece)

The tailpiece is the rectangular or tab-shaped metal extension projecting from the back of the cylinder plug. It is the mechanical link between the rotating cylinder and the bolt mechanism inside the housing. When the key turns the cylinder plug, the plug rotates the tailpiece, and the tailpiece pushes against the cam inside the housing to extend or retract the bolt. This component is visible in the Schlage deadbolt diagram as the piece connecting the cylinder body to the housing assembly behind it.

Tailpiece failures produce a specific symptom: the key turns freely but the bolt does not move. This indicates the tailpiece has broken, deformed, or disengaged from the cam it drives. Browse Schlage deadbolt tailpiece replacement parts at SecurityParts.com.

3. The Outside Rose or Escutcheon

The rose (on standard B Series models) or escutcheon (on trim-specific variants) is the mounting plate visible on the outside face of the door surrounding the cylinder. On the Schlage B60N and B600 Series, this is a circular rose plate that covers the face bore and provides a finished appearance. The rose is held by mounting screws that pass through the door from the inside trim plate, so the rose itself has no external screws that can be removed from outside the door. This design prevents a simple external attack from defeating the trim mounting.

4. The Outside Mounting Plate and Through-Bolts

Behind the outside rose in the diagram are the mounting bolts that pass through the door from the inside trim to hold the entire outer trim assembly. On the B600 Series Grade 1 models, these are hardened machine screws. The diagram shows their path through the door edge and into the interior trim mounting holes. Loose or missing through-bolts produce a wobbling or spinning outer rose and are the most common reason the exterior trim feels loose even when the bolt mechanism is intact.

The Central Assembly: Bolt, Housing, and Faceplate

5. The Deadbolt (Bolt Throw)

The deadbolt itself is the horizontally moving steel bar shown in the center of the diagram, extending from the door edge into the strike box when the lock is in the locked position. On Grade 1 Schlage B Series models (B250, B500, B600 Series), the bolt has a 1-inch throw, meaning it extends one inch beyond the door edge when fully locked. On Grade 2 models (B350, B352), the throw is 5/8 inch.

The bolt face is square-cornered in the Schlage B Series, not beveled. A beveled latch is a spring latch that closes automatically; a square-cornered deadbolt requires deliberate key or thumb turn operation to extend or retract. This distinction is important when reading the diagram: the square face bolt shown is the deadbolt, not the spring latch used in cylindrical locks.

6. The Anti-Saw Pin (Hardened Steel Insert)

The Schlage deadbolt diagram for B600 Series Grade 1 models shows a small pin or cylinder of hardened steel embedded within the bolt body. This is the anti-saw pin. Its function is to defeat a forced entry technique where the attacker saws through the bolt by pressing a hacksaw blade between the door edge and the strike while the bolt is engaged. When the saw blade contacts the anti-saw pin, the pin spins freely inside the bolt body, preventing the blade from making sustained contact and cutting through. Grade 2 models (B350 Series) do not include the anti-saw pin, which is one of the key differences visible between Grade 1 and Grade 2 bolt assemblies in the diagram.

7. The Bolt Housing and Retainer

The bolt housing is the metal case inside the door body that encases the bolt mechanism, the cam assembly, and the tailpiece connection. In the exploded diagram, the housing appears as the central body of the lock into which the cylinder tailpiece enters from one side and the thumb turn cam enters from the other. The housing is secured to the door face by the faceplate screws.

A retainer clip or retaining ring shown in the diagram holds the bolt within the housing so it moves in a straight linear path without rotating. A failed retainer clip causes the bolt to rotate instead of traveling straight, which prevents it from seating correctly in the strike box.

8. The Faceplate and Mortise Pocket

The faceplate is the flat metal plate visible on the door edge when looking at the door from the side. It covers the opening of the mortise pocket cut into the door edge and has two countersunk screw holes that secure the housing to the door. On the B500 and B600 Series, the faceplate is square-corner 1-1/8 inch by 2-1/4 inch. The backset (the horizontal distance from the door edge to the center of the face bore) is adjustable on all Schlage B Series deadbolts between 2-3/8 inches and 2-3/4 inches.

How the adjustable backset works in the diagram: The Schlage B Series bolt housing includes a two-position adjustment for the backset. The faceplate screw holes in the housing align to either the 2-3/8 or 2-3/4 inch position depending on which notch the adjustment plate is set to during installation. No separate parts are required. The same bolt housing serves both backset dimensions. When reading the diagram for replacement purposes, the backset setting affects which strike plate centerline is correct but does not require a different housing or bolt.

The Inside Components: Thumb Turn Side

9. The Thumb Turn

The thumb turn is the knob or lever on the interior face of the door that operates the deadbolt from inside without a key. It connects to a cam inside the housing through a spindle or through-bolt arrangement. Turning the thumb turn 90 degrees rotates the cam, which drives the bolt to the extended or retracted position. In the Schlage B Series diagram, the thumb turn is shown with its cam engagement visible in the exploded view, separate from the thumb turn knob itself.

Thumb turn failures are usually one of two types: the thumb turn spins freely without moving the bolt (broken cam engagement or stripped spindle connection) or the thumb turn is difficult to operate (bent bolt from door-slam damage or misalignment between the bolt and the strike). Identifying which failure type is occurring points directly to which component in the diagram needs replacement.

10. The Inside Rose or Escutcheon

The inside rose mirrors the outside rose in appearance but mounts the interior thumb turn and holds the through-bolts that secure the entire assembly to the door. On B600 Series models, the inside trim includes a more substantial mounting plate behind the rose that anchors the lock body against forced entry attempts from the outside. Removing the inside rose gives access to the through-bolt heads, which allows the entire lock assembly to be removed from the door for service or replacement.

The Strike Assembly: Frame-Side Components

11. The Strike Plate and Strike Box

The strike plate and strike box are shown in the Schlage deadbolt diagram as a separate assembly that mounts into the door frame rather than the door itself. The strike plate is the visible metal plate on the door frame face with a rectangular opening through which the bolt passes. The strike box is the recessed metal box behind the strike plate that receives the full 1-inch bolt throw when the door is locked.

The strike box is a critical security component that most residential installations omit. Without a strike box, the bolt passes through the strike plate opening into wood only. A kick-in attack splits the wood and the bolt pulls through. With a strike box, the bolt enters a metal pocket that distributes the force of a kick-in attack across the full depth of the box, which is substantially more resistant to forced entry. Grade 1 B600 Series installations should always use the provided strike box, not the strike plate alone.

12. Strike Box Reinforcement Screws

The diagram for the B500 and B600 Series strike plate shows two types of screws: standard installation screws (which only penetrate the door jamb) and optional 2-inch reinforcement screws (Schlage part J250-028) that penetrate past the jamb and into the structural framing behind it. The standard screws provide adequate performance for normal use. The 2-inch reinforcement screws dramatically increase the resistance of the strike assembly to kick-in forced entry by anchoring the strike into structural wood rather than just the jamb material. Browse Schlage strike plate and reinforcement parts at SecurityParts.com.

Grade 1 vs Grade 2: What the Diagram Shows Is Different

Grade 1 Diagram (B250, B500, B600 Series)

ANSI/BHMA A156 Grade 1

Bolt throw: 1 inch hardened steel bolt

Anti-saw pin: Present inside bolt body (visible as embedded cylinder)

Strike box: Included, required for full Grade 1 installation

Cylinder: Everest 29 S or T keyway; SFIC/FSIC available on B500/B600

Through-bolt mounting: Hardened machine screws

Typical application: Commercial, institutional, and high-security residential

Grade 2 Diagram (B350 Series)

ANSI/BHMA A156 Grade 2

Bolt throw: 5/8 inch steel bolt

Anti-saw pin: Not present

Strike box: May not be included; strike plate alone

Cylinder: Standard residential keyway; no SFIC/FSIC

Through-bolt mounting: Standard screws

Typical application: Light commercial and residential where Grade 1 is not required

Using the Diagram to Identify the Failed Part

When something goes wrong with a Schlage deadbolt, the symptom usually points directly to a specific numbered component in the diagram. Use this symptom-to-component mapping to identify the right part before ordering.

Key turns, bolt does not moveTailpiece broken or disengaged from cam. Check tailpiece first before replacing cylinder.
Key stiff or hard to turnCylinder plug pins worn or corroded. Lubricate with dry graphite first; replace cylinder if stiffness persists.
Thumb turn spins freelyCam inside housing stripped or thumb turn spindle broken. Requires housing or cam replacement.
Bolt extends but will not retractBolt is bent from door-slam impact or misaligned with strike. Check alignment before replacing bolt assembly.
Bolt will not fully extendStrike box misaligned or door has shifted. Confirm the strike box centerline aligns with the bolt centerline before ordering any parts.
Outside rose spins or wobblesThrough-bolts loose or missing. Tighten through-bolts from inside trim before diagnosing further.
Door can be kicked in despite locked boltStrike box missing or strike screws too short. Install strike box and 2-inch reinforcement screws.

Single Cylinder vs Double Cylinder: Diagram Differences

The most common version of the Schlage B Series deadbolt diagram is the single-cylinder configuration (B60N, B500, B600) where the inside shows a thumb turn and the outside shows a key cylinder. The double-cylinder version (B62N, B502, B602) replaces the thumb turn with a second key cylinder on the interior side.

The diagram difference is significant for parts ordering. A single-cylinder deadbolt uses a thumb turn assembly, a cam, and one cylinder. A double-cylinder deadbolt uses two cylinders, two tailpieces, and no thumb turn or cam assembly. When ordering a replacement cylinder for a double-cylinder installation, both cylinders must be specified to maintain a keyed-alike configuration if both sides share the same key.

Double-cylinder deadbolts and egress compliance: The Schlage deadbolt diagram for double-cylinder models does not include a thumb turn on the inside. This means egress from inside the building always requires a key, which is prohibited on required egress doors in occupied commercial buildings under the IBC and NFPA 101. Double-cylinder deadbolts are appropriate for certain residential applications where a window adjacent to the door creates a security vulnerability, but they must never be installed on commercial egress doors. The Schlage B Series diagram for single-cylinder models is the correct specification for any commercial exit door.

The Adjustable Backset: What It Means for Replacement Parts

Every Schlage B Series deadbolt diagram shows a two-position backset adjustment. The standard backset positions are 2-3/8 inches and 2-3/4 inches, measured from the door edge to the center of the face bore hole. Most commercial door hardware installations use the 2-3/4 inch backset because it is compatible with the wider door stile dimensions common in commercial hollow metal frames. Residential entry doors often use the 2-3/8 inch position.

The backset setting does not change which bolt, housing, or cylinder you need. It changes where the strike plate is positioned on the door frame. A Schlage deadbolt moved from a 2-3/8 inch backset door to a 2-3/4 inch backset door needs the strike plate repositioned but uses the same lock body. Confirming the backset before ordering the strike plate prevents ordering a strike that puts the bolt pocket in the wrong position.

Model Number Reference: B Series Diagram Variants

The Schlage B Series includes several model lines, and the diagram varies slightly between them. Knowing which series is installed before consulting the diagram prevents confusion between models that look similar but use different parts.

The B60N is the most common single-cylinder deadbolt in the residential and light commercial B600 Series. The diagram shows Everest 29 S or T keyway cylinder, 1-inch bolt with anti-saw pin, and square-corner faceplate. The B62N is the double-cylinder version of the same series. The B500 Series and B600 Series are the commercial Grade 1 versions with SFIC and FSIC cylinder options visible in the diagram alongside the standard cylinder. The B250 Series (Grade 1) and B350 Series (Grade 2) are the commercial lines where the Grade difference is reflected in the bolt assembly shown in the diagram.

Browse all Schlage hardware and deadbolt parts at SecurityParts.com, or see the commercial deadbolt parts guide for model-specific identification. For cylindrical lock parts that use a spring latch rather than a deadbolt, see the Schlage cylindrical lock parts catalog. For mortise lock deadbolt assemblies used in L Series locks, see the Schlage mortise lock parts catalog.

Why Choose SecurityParts.com for Schlage Deadbolt Parts

SecurityParts.com has been supplying commercial door hardware parts for over 30 years. We stock OEM Schlage B Series deadbolt components for the complete range including cylinders in all keyway formats, tailpieces, bolt assemblies, strike plates, strike boxes, and reinforcement hardware for B250, B350, B500, and B600 Series deadbolts.

Browse Schlage deadbolt replacement parts by model, the Schlage B Series deadbolt parts guide, and the Schlage strike plate and reinforcement parts guide. Browse the complete SecurityParts.com OEM parts catalog or call 845-935-0301 for same-day parts identification and shipping support.

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OEM vs Aftermarket Commercial Door Hardware Parts: Fire Compliance, Warranties and Safety Monday, July 20, 2026

OEM (Original Equipment Manufacturer) replacement parts from Schlage, Von Duprin, LCN, and Falcon are the only parts that maintain fire door UL listing compliance, preserve Allegion warranty coverage, and guarantee the precise tolerances that safety-critical functions depend on. Aftermarket parts that claim equivalency have been tested to cycle counts under ANSI standards but have not undergone UL fire testing and cannot appear in a fire door Builders Hardware Template (BHT). Installing an unlisted part on a fire-rated door creates a code violation under NFPA 80, voids the assembly's UL listing, and exposes the building owner to liability. The March 2024 Allegion warranty enhancements cover OEM parts from authorized distributors only: Schlage commercial hardware carries 10-year mechanical and 3-year electro-mechanical coverage, and LCN 4040XP carries a 30-year limited warranty.

The price difference between an OEM Von Duprin latch return spring (090039) and a generic equivalent can be as little as a few dollars. The difference in what that purchase decision means for a building's fire door compliance, its NFPA 80 annual inspection record, and the building owner's liability in the event of a fire incident is not measurable in dollars at all. This guide explains what actually separates OEM from aftermarket in commercial door hardware, where aftermarket substitution creates the highest risk, and why SecurityParts.com sources exclusively from authorized channels for every part we carry.

Browse genuine OEM parts at SecurityParts.com: Von Duprin and Falcon exit device parts, LCN door closer parts, Schlage cylindrical lock parts, mortise lock parts, and the complete Allegion parts catalog.

Assembly UL fire ratings cover the complete assembly (door + frame + hardware), not individual components

BHT Builders Hardware Template: the only document that confirms hardware compatibility with a specific fire door model

Mar 2024 Allegion warranty enhancement effective date: 10-year Schlage mechanical, 30-year LCN 4040XP coverage

Separate ANSI grade and UL fire rating are completely independent qualifications: Grade 1 does not equal fire-rated

How UL Fire Door Assembly Listings Actually Work

The most consequential misunderstanding in commercial door hardware is treating the UL fire rating as a property of individual hardware components rather than a property of the complete assembly. A fire door assembly's UL listing covers the specific tested combination of door, frame, and hardware. When Underwriters Laboratories tests a fire door assembly, they test a specific door model from a specific manufacturer, in a specific frame, with specific hardware models installed in specific positions. The listing that results from that test applies to that specific configuration.

This means that a UL-listed Von Duprin 98 series exit device is not automatically compatible with every UL-listed fire door. It is compatible with the fire door models listed in the BHT published by the door manufacturer, because those are the combinations that have been tested together as an assembly. When you replace the Von Duprin 98 with an aftermarket "equivalent" exit device, you have installed an unlisted component. The assembly is no longer in the tested configuration. Whether or not the aftermarket device appears to function identically is irrelevant to the listing status.

The NFPA 80 field modification rule that building owners miss: NFPA 80 Section 5.2 (and its predecessor sections in earlier editions) requires that field modifications to fire door assemblies not affect the assembly's listing. Replacing a listed hardware component with an unlisted component is a field modification that affects the listing. The building owner is responsible for ensuring the assembly remains compliant. When the NFPA 80 annual inspector finds an unlisted part on a fire-rated door, the door is documented as a deficiency. The building owner must then correct the deficiency and document the correction. If the deficiency is not corrected and a fire incident occurs at that door, the non-compliant hardware creates a liability exposure beyond the normal property damage and life safety concerns.

The Builders Hardware Template: The Document Every Locksmith Needs

The BHT is published by each fire door manufacturer and is the authoritative compatibility matrix for hardware on that manufacturer's doors. It lists, by specific model number, which hinges, locks, closers, and exit devices are approved for each door model and fire rating. You can request a BHT from the door manufacturer using the door model number stamped on the door's UL label.

When replacing hardware on a fire door, the correct process is: identify the door's UL label, identify the door manufacturer and model, request the BHT for that door model, confirm the replacement hardware model number appears in the BHT. OEM replacement parts from the same manufacturer and series as the original listed component will appear in the BHT because they were tested with the door. Aftermarket parts cannot appear in the BHT because they were never submitted for testing with that door.

ANSI Grade vs UL Fire Rating: Two Different Qualifications

Hardware buyers frequently use these terms interchangeably. They address completely different performance criteria and are determined by different test standards administered by different bodies.

ANSI/BHMA grades are published by the American National Standards Institute and administered by the Builders Hardware Manufacturers Association. Grade 1 is the heaviest-duty commercial grade, requiring the highest cycle counts (for example, 1,000,000 cycles for cylindrical locks under ANSI/BHMA A156.2), the highest security performance, and the most durable finish. Grade 2 is moderate commercial, and Grade 3 is light residential. These grades say nothing about how the hardware performs in a fire.

UL fire ratings are determined by Underwriters Laboratories under standards such as UL 10C (Positive Pressure Fire Tests of Door Assemblies). Fire testing exposes the complete door assembly to the temperature and pressure conditions of a building fire for the rated duration (20 minutes, 45 minutes, 90 minutes, or 3 hours) and verifies that the assembly maintains its fire separation function throughout. Hardware that is fire-rated must maintain its function (closing, latching, not failing structurally) through the entire fire test duration.

ANSI/BHMA Grade 1 Certification

Tests cycle count durability (1,000,000+ cycles)

Tests security performance under operational load

Tests finish durability under corrosion exposure

Tests door impact resistance

Does NOT test fire performance

Administered by BHMA under ANSI standards

UL Fire Rating (UL 10C)

Tests assembly performance under fire temperature and pressure

Verifies hardware function at elevated temperatures

Tests rated duration: 20, 45, 90 min, or 3 hours

Tests positive pressure from fire-driven air movement

Does NOT test operational cycle count

Administered by Underwriters Laboratories

An aftermarket part that meets ANSI/BHMA Grade 1 cycle count standards has been tested for operational durability. It has not been tested for fire performance. An OEM part that carries both a Grade 1 certification and a UL fire listing has been tested for both. On a fire-rated door, only the part with the UL fire listing is compliant. The ANSI grade of an aftermarket part is irrelevant to its fire door compliance.

High-Risk Parts Where Aftermarket Substitution Is Most Common and Most Dangerous

Critical Risk Exit Device Latch Return Springs

Why this is the highest aftermarket substitution rate

The Von Duprin latch return spring (part 090039 on 98/99 and 22/33A/35A series) is a small, inexpensive component that is available from multiple aftermarket sources. The price difference between OEM and generic appears trivial. The part looks identical to the eye.

Why the substitution creates risk on fire-rated doors

The latch return spring is the component that drives the latch bolt back to the extended (latched) position after every push bar operation. On a fire-rated door, the exit device must latch positively after every single door closure. An aftermarket spring with a slightly lower spring rate (a difference invisible without measurement equipment) will produce a latch that extends more slowly or to a slightly shorter throw on each cycle. Under normal room-temperature conditions, this may be undetectable in operation. Under fire conditions where the mechanism is exposed to elevated temperatures that reduce spring tension further, the already-marginal aftermarket spring may fail to fully extend the latch bolt at the moment the fire door must be reliably latched. This is the exact scenario the fire door assembly is designed to prevent.

The OEM part: Von Duprin 090039

The OEM spring is manufactured to Von Duprin's specifications for spring constant, wire diameter, coil count, and free length. It is the component that was installed in the device during UL fire testing. Browse the Von Duprin exit device parts catalog at Security Parts for the 090039 and all related exit device springs.

Critical Risk Door Closer Hydraulic Cylinder Assemblies

Why aftermarket closer cylinders are common

Replacement hydraulic cylinder assemblies for LCN 4040XP and related series are ordered when the original cylinder develops a hydraulic oil leak. Aftermarket cylinder assemblies exist at significantly lower price points than OEM assemblies. The price difference is visible; the performance difference is not visible at the time of installation.

Why the substitution creates compliance and safety risk

The door closer cylinder is the component that determines closing speed through the hydraulic circuit's flow characteristics. An aftermarket cylinder with different internal orifice diameters, different hydraulic fluid viscosity, or different seal materials will produce different sweep and latch speeds than the OEM cylinder for the same valve settings. On an ADA-accessible door where the closer must produce no more than 5 pounds of opening force and must take at least 5 seconds from 90 degrees to 12 degrees from the latch, an aftermarket cylinder that alters the spring force delivery changes the actual opening force independent of the spring size dial setting. A closer that passed ADA compliance at installation with an OEM cylinder may not comply with the same spring size setting after an aftermarket cylinder is installed.

On fire-rated doors, a closer with an aftermarket cylinder whose different hydraulic characteristics produce insufficient closing force at the final latching phase may fail to latch the door against its seals, compromising the fire separation. Browse LCN OEM cylinder assemblies and closer parts at Security Parts.

High Risk Electric Strike Solenoid Assemblies

The voltage sensitivity that makes solenoid substitution dangerous

Von Duprin electric strike solenoids (in the 5100, 6100, 6200, and 6300 series) are specified for either 12V or 24V DC operation, and in some cases multi-voltage. The OEM solenoid is wound with a specific number of turns of wire at a specific gauge to produce the correct magnetic actuation force at the specified voltage. An aftermarket solenoid wound to a different specification may produce either insufficient actuation force (the strike fails to release on an access control signal) or excessive current draw (the solenoid overheats and fails prematurely).

This is not a theoretical risk. A 12V solenoid installed in a 24V system burns out immediately. A 24V solenoid installed in a 12V system will not actuate reliably under load. An aftermarket solenoid with the correct voltage label but different coil winding specifications will draw incorrect current and produce incorrect actuation force, without any visible indication at installation. Browse Von Duprin electric strike OEM parts at SecurityParts.

High Risk Deadlatch Assemblies for Mortise Locks

Deadlocking plunger tolerances are precision specifications

The deadlatch in a Schlage L Series or ND Series cylindrical lock incorporates a deadlocking plunger whose position relative to the main latch bolt determines whether the latch deadlocks when the door closes. The plunger must extend to a precise dimension alongside the latch bolt so that it contacts the strike plate face when the door is fully closed. When the plunger contacts the strike face, it locks the latch bolt in the extended position, preventing the latch from being pushed back without operating the lever or key.

Aftermarket deadlatch assemblies with plunger dimensions outside the OEM specification produce a deadlatch that either fails to contact the strike face (providing no deadlocking protection that is visually undetectable) or contacts the strike face prematurely (increasing latch resistance and generating false latching complaints). Either deviation from OEM specification creates a security vulnerability or a maintenance problem. Browse Schlage L Series OEM deadlatch parts and ND Series OEM latch parts at Security Parts.

Allegion Warranty Coverage for OEM Parts

Allegion (the parent company of Schlage, Von Duprin, LCN, Falcon, and related brands) enhanced its Limited Product Warranty effective March 1, 2024. These warranties apply exclusively to OEM parts purchased through authorized distribution channels and installed correctly per manufacturer specifications.

Schlage Commercial Mechanical

10 Years Mechanical warranty on commercial cylindrical and mortise lock hardware (ND Series, L Series, B Series). 3-year electro-mechanical warranty on electrified locks.

LCN 4040XP Door Closer

30 Years LCN 4040XP Series limited warranty covering manufacturing defects. One of the longest warranty terms in commercial door hardware.

Von Duprin Exit Devices

Limited Von Duprin covers manufacturing defects in materials and workmanship on exit devices purchased through authorized distribution. Mechanical warranty on most series.

Falcon Hardware

Limited Falcon mechanical hardware warranty covers manufacturing defects through authorized channels. Confirm warranty terms by product series with SecurityParts.com at time of order.

What happens to warranty coverage when aftermarket parts are installed: Allegion's warranty covers the OEM product against manufacturing defects. When an aftermarket part is installed alongside or in place of an OEM component, Allegion's warranty does not cover the aftermarket part. More importantly, if the aftermarket part causes damage to adjacent OEM components (for example, an aftermarket closer arm with incorrect geometry that accelerates spindle wear on an OEM closer cylinder), the resulting damage to the OEM components may not be covered under warranty either because the damage was caused by the non-warranted aftermarket component. The practical implication: an aftermarket part whose failure requires replacing the OEM closer cylinder alongside it means the building pays for both the failed aftermarket part and the OEM replacement, with no warranty recovery on either.

How to Identify Genuine OEM Parts vs Aftermarket Copies

Several indicators distinguish genuine OEM Allegion brand parts from aftermarket copies at the point of order or receipt.

Manufacturer Part Number Verification

Every OEM Allegion part carries a specific manufacturer part number that corresponds to the manufacturer's catalog. Von Duprin parts use numeric codes (090039, 050711, 090041). Schlage parts use alphanumeric codes (16-228, 10-094, ND10S). LCN parts use series-based codes (4040XP-RW, 4040XP-62PA). These part numbers appear in the manufacturer's official catalog and can be verified against the manufacturer's website or by calling SecurityParts.com. An aftermarket copy may claim the same part number for cross-reference purposes, but the actual part will not have the number printed or stamped on it by the manufacturer.

Manufacturer Packaging

Genuine OEM parts ship in manufacturer-branded packaging with the manufacturer's name, the part number, and typically a description of the component. Von Duprin parts ship in Allegion-branded packaging. Schlage parts ship in Schlage-branded packaging. A part that arrives in a plain white box or in packaging with only a cross-reference number and no manufacturer branding is very likely aftermarket regardless of what the seller claims.

Purchase from Authorized Distributors

The most reliable way to guarantee OEM authenticity is purchasing from an authorized Allegion distributor. Authorized distributors source directly from Allegion's distribution network and cannot substitute aftermarket parts under the authorized distributor agreement. SecurityParts.com is an authorized supplier of Allegion brand parts including Schlage, Von Duprin, LCN, and Falcon. All parts in the catalog are sourced from authorized channels. Browse the complete OEM parts catalog .

The Amazon and eBay aftermarket risk that facility managers underestimate: Search for "Von Duprin 090039" or "LCN 4040XP arm" on major online marketplaces and you will find listings that appear to be the genuine OEM part but are actually aftermarket copies. The sellers frequently use the OEM part number as the product title for search visibility, but the item shipped is manufactured by an unknown third party. On a non-fire-rated interior door, the consequence of an aftermarket spring with slightly lower spring rate is a latch that fails a year sooner than expected. On a fire-rated door, the consequence in a fire event can be the door failing to latch when it must. The risk differential is not reflected in the price differential. Always purchase fire door hardware parts from authorized distributors.

The Specific Parts Where OEM vs Aftermarket Matters Most at SecurityParts.com

Part Category	Risk Level	OEM Source	Browse
Von Duprin exit device latch springs	Critical (fire door latching)	Allegion / Von Duprin 090039, 090041	Exit Device Parts
LCN door closer cylinder assemblies	Critical (ADA and fire door closing)	Allegion / LCN OEM cylinders	LCN Parts
Von Duprin electric strike solenoids	High (access control reliability)	Allegion / Von Duprin OEM solenoids	Electric Strike Parts
Schlage deadlatch assemblies	High (deadlocking function)	Allegion / Schlage 16-228, 16-260	Mortise Lock Parts
Schlage cylindrical latch assemblies	High (THP-8201, THP-8219)	Allegion / Schlage OEM latches	Cylindrical Lock Parts
Von Duprin dogging components	Moderate (dogging reliability)	Allegion / Von Duprin 050711, 090041	Von Duprin Parts
Schlage B Series deadbolt strikes	Moderate (fire door strike compliance)	Allegion / Schlage 10-087, 10-094	Deadbolt Parts

Pre-order parts authenticity and compatibility support at 845-935-0301 or the contact page.

Why Security Parts for OEM Allegion Brand Parts

Authorized distribution, full Allegion warranty, OEM-only sourcing, same-day shipping, and the BHT compatibility guidance that protects fire door compliance.

Authorized OEM Source

Every part in the SecurityParts.com catalog is sourced from authorized Allegion distribution channels. No aftermarket substitutions. Full Allegion warranty coverage on all Schlage, Von Duprin, LCN, and Falcon parts.

BHT Compliance Support

We document the BHT compatibility requirement and can support verification that an OEM replacement part maintains fire door assembly compliance. Aftermarket suppliers cannot provide this documentation.

Fire Door Risk Clarity

We document specifically which parts carry the highest aftermarket substitution risk and why. No other parts supplier documents the mechanism by which an aftermarket spring creates fire door latching risk at elevated temperatures.

Same-Day Shipping

OEM Allegion parts ship same day from US warehouses. Call 845-935-0301 or contact us for part number confirmation and fire door compliance support.

What Makes SecurityParts.com Different for OEM Parts Supply

We document the BHT as the authoritative fire door hardware compatibility document and explain why aftermarket parts cannot appear in any BHT. This is absent from all competitor parts supplier content and is the core reason fire door compliance requires OEM parts.
We document the elevated-temperature failure mode for aftermarket latch return springs: a spring with a marginally lower spring rate may function normally at room temperature but fail to fully extend the latch bolt at the temperatures a fire door faces during a fire event. No competitor documents this specific failure mechanism.
We document the aftermarket cylinder ADA compliance risk: an aftermarket closer cylinder with different hydraulic characteristics changes actual opening force independent of the spring size dial, making ADA compliance verification unreliable after a non-OEM cylinder installation.
We document the March 2024 Allegion warranty enhancements: Schlage commercial 10-year mechanical, LCN 4040XP 30-year limited. These warranties apply to OEM parts from authorized sources only. Aftermarket parts carry no Allegion warranty and may invalidate adjacent OEM component coverage when their failure causes collateral damage.
We source exclusively from authorized Allegion distribution channels. All parts carry full manufacturer warranty. Browse exit devices, door closers, cylindrical locks, and all Allegion brand parts at SecurityParts.com.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Frequently Asked Questions About OEM vs Aftermarket Commercial Door Hardware Parts

Does installing an aftermarket part on a fire-rated door void the UL listing?

In most cases, yes. A fire door assembly's UL listing covers the specific tested combination of door, frame, and hardware. Replacing a listed component with an unlisted aftermarket part means the assembly is no longer configured as tested. NFPA 80 requires field modifications not to affect the assembly's listing. The BHT (Builders Hardware Template) from the door manufacturer is the authoritative document confirming which replacement parts maintain compliance. OEM parts from the same manufacturer and series appear in BHTs. Aftermarket parts cannot appear in any BHT because they were never tested with fire door assemblies.

What is the Builders Hardware Template and why does it matter for replacement parts?

The BHT is the compatibility matrix published by each fire door manufacturer listing exactly which hardware models (by specific manufacturer and model number) are approved for each door model and fire rating. It is the only document that confirms hardware compatibility with a specific fire door. OEM replacement parts from the same manufacturer and series as the original listed hardware appear in BHTs. Aftermarket parts have no BHT presence. When replacing hardware on a fire-rated door, request the BHT from the door manufacturer using the model number on the door's UL label and confirm the replacement part appears in it.

What is the difference between ANSI grade and UL fire rating on commercial door hardware?

ANSI/BHMA grades measure operational performance: cycle count, security, and finish durability. Grade 1 requires 1,000,000 cycles for cylindrical locks. UL fire ratings measure assembly performance under fire temperature and pressure conditions under standards like UL 10C. These are completely separate qualifications by different testing bodies. A Grade 1 lock is not fire-rated, and a fire-rated lock is not automatically Grade 1. Aftermarket parts that claim Grade 1 equivalency have been tested for cycle count only, not for fire performance. On fire-rated doors, only UL fire-listed OEM parts are compliant.

What Allegion warranty coverage applies to Schlage, Von Duprin, and LCN OEM parts?

Following the March 2024 Allegion warranty enhancements: Schlage commercial mechanical hardware carries 10-year mechanical and 3-year electro-mechanical warranty. LCN 4040XP carries a 30-year limited warranty. Von Duprin exit devices carry a limited mechanical warranty covering manufacturing defects. All warranties apply to OEM parts from authorized distributors installed correctly. Aftermarket parts carry no Allegion warranty and may affect warranty coverage on adjacent OEM components when their failure causes collateral damage.

Which specific commercial door hardware parts carry the highest risk from aftermarket substitution?

Four highest-risk categories: exit device latch return springs (fire door latching reliability at elevated temperatures depends on precise spring constants); door closer hydraulic cylinders (different orifice specifications alter ADA opening force and fire door closing characteristics); electric strike solenoids (voltage-sensitivity and coil winding differences cause premature failure or inconsistent actuation); and deadlatch assemblies (plunger tolerance deviations prevent correct deadlocking even when the latch appears to function). All four are available as genuine OEM parts at Security Parts.

How can I verify that a replacement part is genuine OEM and not an aftermarket copy?

Genuine OEM Allegion parts carry the manufacturer's part number printed, stamped, or labeled on the part or packaging. Part numbers follow the manufacturer's catalog system (Von Duprin five to six digit numeric codes, Schlage alphanumeric codes, LCN series-based codes). OEM parts ship in manufacturer-branded packaging. Purchase from authorized distributors like SecurityParts.com, which sources exclusively from authorized Allegion distribution channels. Avoid marketplace listings that use OEM part numbers as search titles while shipping generic parts in plain packaging. Call 845-935-0301 to verify a part number's OEM status before installing on a fire-rated door.

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Commercial Door Hardware Maintenance Schedule and NFPA 80 Inspection Guide Friday, July 17, 2026

Commercial door hardware requires four levels of maintenance: monthly (visual check for oil leaks, operating force test, latch return verification), quarterly (fastener tightening, lubrication, dogging verification on exit devices), semi-annual (closer valve adjustment, cylinder cleaning, ADA force re-test, rod guide inspection), and annual (NFPA 80 fire door assembly inspection, cycle assessment, full hardware evaluation). NFPA 80 requires annual fire door inspections by a qualified person with written records. Mechanical dogging of fire-rated exit devices is prohibited. WD-40 is never the correct lubricant for commercial door hardware. Replace latch return springs proactively on high-cycle devices during annual inspection. Door closer oil leaks require immediate replacement, not adjustment.

Preventive maintenance on commercial door hardware is not optional in any building with fire-rated doors. NFPA 80 mandates annual inspections by a qualified person, with written records kept available for the Authority Having Jurisdiction. Beyond the code minimum, a structured maintenance schedule prevents the three outcomes that cost facility managers the most: emergency service calls on doors that fail at the worst time, ADA non-compliance citations triggered by a closer that drifted out of adjustment between annual visits, and fire door deficiencies that expose the building owner to liability when an inspection finds conditions that have been building for months.

For OEM replacement parts on every component covered in this guide, browse Von Duprin and Falcon exit device parts, LCN door closer parts, Schlage cylindrical lock parts, mortise lock parts, and the complete all products catalog at Security Parts.

Annual Minimum NFPA 80 fire door inspection frequency (Section 5.2.4), with written records required

2025 ed. Current NFPA 80 edition; 2022 edition most widely enforced; CMS follows 2010 edition

Prohibited Mechanical dogging of fire-rated doors (only electromagnetic/EL hold-open is code-compliant)

Never WD-40 on commercial door hardware: it is a solvent, not a lubricant, and accelerates wear

Why Preventive Maintenance Intervals Matter More Than You Think

Hardware manufacturers specify cycle ratings based on controlled testing conditions. Real commercial buildings do not match controlled testing conditions. Temperature extremes, humidity, construction dust, vandalism, and simple improper use all accelerate wear beyond the rated cycle life. A Von Duprin 98/99 rated for 2,000,000 cycles in a school main corridor that takes 1,000 cycles per day has a theoretical 5-year mechanical life before its first expected component failure. A hospital ICU corridor door rated the same that operates at 800 cycles per day may see its first latch spring failure at 3 to 4 years.

Maintenance intervals exist to catch wear before it becomes failure. The cost difference is not trivial: a proactive latch spring replacement (Von Duprin 090039, under $20) costs a fraction of an emergency locksmith call after a fire door stops latching at 2 AM. A closer valve adjustment takes 5 minutes; an ADA complaint and remediation can take weeks.

Hardware Cycle Life Reference

2,000,000 Von Duprin 98/99 and 22/33A/55/75/88 series exit devices (ANSI A156.3 Grade 1)

10,000,000 LCN 4040XP door closer (ANSI/BHMA A156.4 Grade 1 rating)

1,000,000 Schlage ND Series cylindrical lock (ANSI/BHMA A156.2 Grade 1)

1,000,000 Schlage L Series mortise lock (ANSI/BHMA A156.13 Grade 1)

These cycle ratings are the total mechanical test cycles to specification, not recommended service intervals. A door that sees 500 cycles per day reaches 1,000,000 cycles in approximately 5.5 years. The practical maintenance implication is that high-cycle doors need more frequent component inspection even if the hardware appears functionally normal. Spring fatigue, bearing wear, and seal degradation begin well before total mechanical failure.

Monthly Maintenance Checks

Monthly Visual and Functional Verification

Monthly checks take 3 to 5 minutes per door and catch the conditions that develop quickly between quarterly visits. No tools are required for most of these checks.

Exit Devices: Monthly Checks

Depress and release the push bar: confirm the latch bolt snaps back to full extension immediately. Any hesitation or partial extension is a failed latch return spring.
Check the dogging indicator window on current Von Duprin devices. A red indicator means the device is mechanically dogged. Verify this is intentional and authorized. On fire-rated doors, mechanical dogging is prohibited under any circumstances.
Close the door from outside and push inward without operating the bar. The door must not open. If it does, the latch is not extending or not engaging the strike.
Verify all push bar mounting fasteners are tight. A loose push bar shifts the cam geometry and changes latch operation.

Door Closers: Monthly Checks

Inspect the closer body for any oil film or dripping. A leaking closer must be replaced at the next available service window. If the leak is severe or if the closer is no longer controlling the door, replace immediately.
Open the door 90 degrees and let go. Time the sweep from 90 degrees to 12 degrees from the latch. If it takes less than 5 seconds on an accessible route door, note it for quarterly valve adjustment.
Observe the closer arm during door operation for bounce, rattle, or audible clicking. These indicate loose fasteners at the spindle, knuckle, or shoe.

Locks and Latches: Monthly Checks

Operate the lever or knob on cylindrical and mortise locks. Confirm it returns to the horizontal position immediately after release. A drooping lever means a failed lever return spring.
Close the door slowly and observe the latch bolt entering the strike pocket. It should enter cleanly without contacting the strike face. Any contact mark on the strike face indicates misalignment.
Verify all visible exposed fasteners on the lock trim are tight. Loose trim shifts the lever geometry and accelerates chassis wear.

The monthly check that ADA compliance officers measure first: On every accessible route door, the monthly check should include measuring the opening force with a push-pull gauge at the door face, perpendicular to the door from a fully closed position. ADA Section 404.2.9 limits interior non-fire doors to 5 lbf. Most facility maintenance programs skip this measurement because the door "feels fine." A closer adjusted to 4.8 lbf in June will regularly exceed 5 lbf in December in cold climates due to hydraulic fluid thickening. Monthly opening force verification catches seasonal drift before an inspection finds it first.

Quarterly Maintenance Tasks

Quarterly Fastener, Lubrication, and Function Checks

Quarterly tasks require a screwdriver set, hex key set, torque wrench for closer arm fasteners, and dry lubricant (graphite or PTFE spray). On high-traffic doors, quarterly visits often catch emerging problems before they generate service calls.

Exit Devices: Quarterly Tasks

Tighten all mounting fasteners: the sex bolt assemblies through the door, the mechanism case mounting screws, and the push bar end cap screws.
Apply dry lubricant (PTFE or graphite) to the push bar pivot axle. Never use oil-based lubricant on the mechanism case interior: it collects dust from corridor traffic and gums the mechanism.
On vertical rod devices, inspect all rod guides for tightness and correct alignment. A single loose guide allows the rod to bow, absorbing push bar motion before it reaches the top or bottom latch.
Verify the top and bottom latches on SVR devices extend and retract smoothly by operating the push bar several times while watching each latch directly.
Check that no modifications have been made to the device that would affect its UL fire listing: no added brackets, no taped or painted-over latch mechanisms, no field-drilled holes in the mechanism case.

Door Closers: Quarterly Tasks

Tighten all three connection points: the arm-to-spindle fastener, the arm knuckle keeper or set screw, and the shoe-to-header fasteners. Use a torque wrench and the manufacturer's specified torque values where available.
Re-verify sweep timing (90 degrees to 12 degrees from latch, minimum 5 seconds for ADA) and measure opening force at the door handle. Adjust S and L valves if needed following the S-first, then L, then B sequence.
Confirm backcheck engages at the correct point (approximately 70 to 75 degrees of opening on exterior doors). A closer without backcheck on an exterior door is at risk of arm damage from wind or from people pushing the door against the wall.

Locks and Strikes: Quarterly Tasks

Clean the lock keyway with compressed air to remove accumulated lint, dust, and graphite buildup. Then apply a small amount of fresh graphite powder to the keyway.
Apply dry PTFE spray to the latch bolt face and the interior of the strike pocket. Wipe away any excess before it accumulates and attracts dust.
Check all strike mounting screws. Tighten any that have loosened. On wood frames, if the screw hole is stripped, use a longer screw to reach fresh wood before the next quarterly visit.

Semi-Annual Maintenance Tasks

Semi-Annual Calibration, Cleaning, and Condition Assessment

Semi-annual tasks go deeper than quarterly and require a calibrated push-pull force gauge for ADA verification and a straightedge for door warpage assessment. Schedule semi-annual visits in early summer and mid-winter to catch seasonal drift in both directions.

Exit Devices: Semi-Annual Tasks

With the door closed, verify the latch bolt extends fully into the strike pocket and the strike pocket walls provide positive engagement. The latch bolt should not be able to be pushed back from outside with finger pressure when the door is closed and the push bar is in the rest position.
On deadlatch cylindrical locks paired with exit device trim, confirm the deadlocking plunger contacts the strike plate face when the door closes. If the strike has drifted or the door has shifted, the plunger may hang in open air rather than contacting the face.
Lubricate the cylinder keyway on any keyed outside trim attached to the exit device with graphite powder. Cylinder lubrication on exit device outside trim is frequently missed in standard lock maintenance programs because the cylinder is on the outside of an exit device rather than a lock body.

Door Closers: Semi-Annual Tasks

Perform full ADA opening force measurement with a calibrated gauge. Do not rely on the valve position alone: actual opening force depends on the door weight, hinge friction, weather seal compression, and threshold resistance, all of which change with temperature and seasonal humidity. Record the measurement for comparison.
If the closer was adjusted in summer, re-verify opening force in winter. Hydraulic fluid thickens at lower temperatures and may push a compliant summer reading over the 5 lbf ADA limit by January.
Inspect the cover for any oil accumulation. If oil is inside the cover but not dripping from the body, the seal is beginning to fail. Plan for replacement at the next convenient window before the seal fails completely and oil appears on the door or floor.

Door and Frame: Semi-Annual Assessment

Check door warpage with a straightedge held against the lock edge of the door from top to bottom. Warpage exceeding 1/4 inch in a 7-foot door prevents consistent latching regardless of hardware condition. Document the warpage measurement.
Inspect hinge pins for wear grooves. A worn hinge pin allows the door to drop between adjustments. The door drop shifts the latch bolt position relative to the strike, requiring periodic strike adjustment that masks the real hinge pin failure.
On fire-rated door assemblies, inspect the intumescent seals at all four edges for damage, compression, or gaps. Damaged or missing intumescent seal requires immediate replacement to maintain the fire rating.

The semi-annual check that most maintenance programs miss on SVR devices: Surface vertical rod exit devices on doors that have seen heavy use for several years frequently develop a subtle rod guide problem: the guides remain physically attached but the guide bracket has rotated slightly so the rod is no longer centered in the guide channel. The rod still moves when the push bar is pressed but now rubs against the guide edge on every cycle, increasing push bar operating force and accelerating wear on both the rod and the guide. You can only detect this by pressing the push bar and watching the rod at every guide location along the door edge. If the rod touches the guide wall rather than moving through the center of the channel, the guide bracket needs realignment.

Annual Maintenance and NFPA 80 Fire Door Inspection

Annual NFPA 80 Compliance Inspection and Full Hardware Evaluation

The annual inspection covers all monthly, quarterly, and semi-annual tasks plus the NFPA 80 fire door assembly inspection requirements. Written records of the annual inspection must be maintained for each fire-rated door assembly and made available to the AHJ on request.

NFPA 80 Annual Fire Door Inspection Requirements

Verify the fire door label is visible, legible, and permanently attached to the door and to the frame. A door or frame without a legible label does not comply with NFPA 80 regardless of its condition.
Confirm the door closes and latches from the full open position without any secondary action: no propping, no manual latching, no pushing the door into the frame after it stops. The door must latch on its own from any open position.
Verify the exit device is not mechanically dogged. If the facility has been using dogging on fire-rated doors, this must be corrected immediately as a life-safety code violation.
Check all door frame clearances: the clearance at the top and latch edge must not exceed 1/8 inch, and the clearance at the bottom must be consistent with the fire rating of the assembly. Excessive clearance means smoke can pass through gaps even when the door is closed.
Confirm no field modifications have been made to the door or frame that affect the fire rating: no additional holes, no unauthorized vision panels, no non-listed hardware installed in place of listed hardware.
On exit devices, verify the UL listing label is present on the device mechanism case. An unlisted device on a fire-rated door creates a non-compliant assembly.
Document all findings with the door number, date of inspection, inspector name and qualification, conditions found, and any corrective actions required. The record must be retained and available for AHJ review.

Who Can Perform the NFPA 80 Annual Inspection?

NFPA 80 requires inspection by a "qualified person" who has knowledge and understanding of the operating components and the type of fire door being tested. NFPA 80 places the definition of "qualified" subject to the AHJ's interpretation. Some jurisdictions accept trained in-house maintenance personnel; others require DHI certification, NFPA 80 training certification, or a fire protection license. Check with the local AHJ and the building's insurance carrier before designating who performs the inspection. Healthcare facilities under CMS jurisdiction face additional credentialing requirements tied to the 2012 NFPA 101 adoption by CMS.

The CMS healthcare door inspection requirement that surprises many hospital facility managers: Healthcare facilities under CMS jurisdiction (Medicare and Medicaid certified hospitals, nursing facilities, and ambulatory surgery centers) follow NFPA 80 as adopted by the 2012 edition of NFPA 101, which is CMS's referenced standard. The 2012 NFPA 101 uses the 2010 edition of NFPA 80. This means that a healthcare facility that assumes it is following the current 2022 or 2025 edition of NFPA 80 may actually be subject to the 2010 edition's requirements. During CMS surveys, inspectors specifically check fire door compliance against the 2012 NFPA 101 framework. Confirm the applicable edition with the facility's compliance officer before the annual inspection.

Annual Hardware Replacement Assessment

The annual inspection is the right time to assess whether hardware has reached the end of its practical service life. The replacement indicators below are not cycle-count formulas: they are observable conditions that indicate the hardware will not perform reliably for another annual cycle.

Component	Replace When	Part at SecurityParts.com
Von Duprin latch return spring	Latch hesitates or does not fully extend after push bar release; on 5+ year high-cycle devices, replace proactively at annual	Exit Device Parts (090039)
LCN door closer	Any oil on the closer body; sweep or latch speed cannot be controlled with valve adjustment; arm bounces with all fasteners tight	Door Closer Parts
Schlage cylindrical latch assembly	Latch bolt does not return to full extension; latch rubs strike face despite correct strike alignment	Cylindrical Lock Parts
Schlage mortise deadlatch	Deadlocking plunger fails to contact strike face; bolt retracts under pressure without lever operation	Mortise Lock Parts (16-228, 16-260)
Strike plate	Strike pocket visibly worn, deformed, or corroded; bolt engagement is no longer positive with door fully closed	Deadbolt/Strike Parts
Von Duprin dogging components	Dogging won't hold after latching; dog key doesn't fully engage; dogging hook visibly worn	Von Duprin Parts (090041, 090044)

NFPA 80 Annual Inspection: What It Does Not Cover

NFPA 80 covers fire door assemblies specifically. It does not establish the maintenance requirements for non-fire-rated door hardware, and it does not address ADA opening force compliance, which is governed by ADA Standards Section 404.2.9 and the applicable state code. A door that passes NFPA 80 inspection may still violate ADA opening force requirements, and vice versa.

Many facilities treat the NFPA 80 annual inspection as their entire door hardware maintenance program. This misses the quarterly and semi-annual tasks that prevent the conditions the annual inspection finds. The annual inspection documents conditions; the quarterly and semi-annual visits prevent them from developing in the first place.

Lubricant Selection for Scheduled Maintenance

Component	Correct Lubricant	Application Method	Frequency
Lock cylinder keyway	Dry graphite powder or PTFE spray	Spray into keyway; insert and remove key several times	Quarterly
Latch bolt face	Dry PTFE spray	Spray on bolt face; wipe excess	Quarterly
Strike pocket interior	Dry PTFE spray	Light spray into pocket; wipe excess before accumulation	Quarterly
Hinge pin and knuckle	Lithium grease or PTFE lubricant	Apply to pin and knuckle; cycle door full swing several times	Semi-annual
Exit device push bar axle	Light machine oil at pivot point only	Drop or spray; cycle bar several times; wipe visible excess	Quarterly
Door closer body	None: sealed hydraulic unit	Do not lubricate. Oil on the body indicates seal failure.	N/A
Deadbolt throw faces	Dry PTFE or graphite spray	Spray bolt tip and face; cycle lock several times	Semi-annual

Browse all replacement parts for Von Duprin, LCN, Schlage, Falcon, and Detex at SecurityParts.com: exit devices, door closers, cylindrical locks, mortise locks, electric strikes, and all products. Pre-order parts support at 845-935-0301 or contact page.

Why Choose SecurityParts.com for Your Maintenance Parts Program

Cycle life data, NFPA 80 compliance guidance, CMS healthcare edition warning, proactive spring replacement program, and same-day shipping on all OEM parts.

Cycle Life Data

We document the rated cycle life for Von Duprin, LCN, and Schlage hardware and show how high-cycle applications reach theoretical replacement intervals much faster than most maintenance programs account for.

CMS Edition Warning

We document that healthcare facilities under CMS jurisdiction follow the 2010 edition of NFPA 80 via the 2012 NFPA 101 adoption, not the current 2022 or 2025 edition. This distinction surprises many hospital facility managers before CMS surveys.

SVR Rod Guide Diagnosis

We document the rotated rod guide failure mode on SVR exit devices where the guide remains attached but allows the rod to rub against the guide wall. This failure increases push bar force and accelerates wear without any visible indication from a standard visual inspection.

Same-Day Shipping

Most OEM replacement parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for part identification and compatibility support.

What Makes Security Parts Different for Maintenance Program Support

We document the CMS healthcare NFPA 80 edition discrepancy: CMS facilities follow the 2010 edition, not the current 2022 or 2025 edition. This creates a real risk of incorrect compliance assumptions before CMS surveys and is not documented in any general maintenance content.
We document the proactive latch return spring replacement recommendation for high-cycle Von Duprin devices during annual NFPA 80 inspection. No other parts supplier documents a proactive replacement strategy for this specific failure-prone component.
We document the SVR rod guide rotation failure mode where the guide bracket remains attached but the rod rubs the guide wall rather than moving through the channel center. This is detectable only by observing the rod at each guide during push bar operation.
We document the monthly ADA opening force measurement as a compliance practice, not just an annual task. Seasonal hydraulic fluid thickening causes drift between annual inspections that monthly measurements catch before an inspection finds a violation.
We carry Von Duprin exit device parts, LCN door closer parts, Schlage cylindrical lock parts, and all supporting components for a complete preventive maintenance parts program in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Frequently Asked Questions About Commercial Door Hardware Maintenance and NFPA 80

How often does NFPA 80 require fire door assemblies to be inspected?

NFPA 80 Section 5.2.4 requires annual inspection at minimum, immediately after initial installation and then yearly. Inspections must be performed by a qualified person with knowledge of the operating components and fire door type. Written records of each inspection must be maintained and available for AHJ review. The 2022 edition is the most widely enforced; the 2025 edition is the most current. Healthcare under CMS follows the 2010 edition via the CMS-adopted 2012 NFPA 101.

What does the NFPA 80 annual fire door inspection require for exit device hardware?

The inspection requires: positive latching on every closure without secondary action, no mechanical dogging on fire-rated doors (prohibited), push bar returns to rest freely, latch bolt engages strike fully, no unauthorized modifications affecting the UL listing, and visible legible UL listing label on both the device and the door and frame. Written documentation of all findings is required for each assembly inspected.

How often should exit device latch return springs be replaced as preventive maintenance?

Replace when the latch hesitates or does not snap back immediately after push bar release. On high-cycle doors (hospital corridors, school main entries, 500 to 1,000 cycles per day), proactive replacement of the Von Duprin 090039 spring during the annual NFPA 80 inspection is cost-effective on devices over 5 years old. The spring costs less than $20 and prevents a fire door latching failure between scheduled visits.

What is the cycle life of an LCN 4040XP door closer and when should it be replaced?

The LCN 4040XP carries a 10,000,000-cycle ANSI/BHMA A156.4 Grade 1 rating. In practice, replace when oil appears on the closer body (seal failure, cannot be repaired), when sweep or latch speed cannot be controlled after correct valve adjustment, or when the closer is more than 15 to 20 years old on an exterior high-traffic door regardless of visible condition. Seal degradation from temperature cycling typically begins before visible leaking appears.

How often should commercial cylindrical locks be rekeyed as a security practice?

Rekey based on events, not intervals: key not returned at end of employment, security incident at the door, or change of tenants. For master keys and perimeter keys, audit at every personnel change. Restricted keyways (Schlage Everest 29 R or T family) significantly extend effective security intervals by preventing unauthorized key duplication. Open keyway cylinders offer no key control between rekeying events.

What lubricant should be used during scheduled commercial door hardware maintenance?

Lock keyways: dry graphite powder or PTFE spray (quarterly). Latch bolts and strike pockets: dry PTFE spray (quarterly). Hinge pins: lithium grease or PTFE lubricant (semi-annual). Exit device push bar axle pivot: light machine oil at pivot only (quarterly). Door closer bodies: no lubricant ever. A closer that needs lubrication to function has a failed seal and requires replacement. Never use WD-40 on any commercial door hardware: it is a solvent that leaves residue attracting dust and accelerating wear.

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Commercial Door Hardware Troubleshooting Guide: Exit Devices, Closers, Locks and Strikes Thursday, July 16, 2026

This guide covers eight commercial door hardware failure scenarios with root cause diagnosis and specific OEM replacement parts. A leaking door closer must be replaced: no valve adjustment fixes a failed seal. An exit device that won't latch after the door closes is most likely dogged, has a failed latch return spring, or has a displaced rod guide on SVR devices. A latch not catching the strike is usually a strike alignment issue, a failed latch spring, or paint-filled strike pocket. A door closer not fully closing the door is typically a latch speed valve issue, undersized spring, door warpage over 1/4 inch, or HVAC stack pressure. All replacement parts for Von Duprin, LCN, Schlage, Falcon, and Detex hardware are available at SecurityParts.com with same-day shipping.

Most commercial door hardware failures are not random. Each component has a specific set of failure modes that occur in a predictable order based on the number of cycles, the operating environment, and the installation quality. A technician who knows these patterns can diagnose and resolve the correct issue on the first visit rather than replacing components until something works. This guide covers the eight failures that generate the most service calls across commercial buildings, with part-number-level solutions for each.

Browse replacement parts at SecurityParts.com: exit device parts, door closer parts, cylindrical lock parts, mortise lock parts, and all parts by brand and series.

1/4 inch Door warpage threshold beyond which no closer adjustment restores consistent latching

No fix A leaking hydraulic door closer: oil on the body means the seal has failed and only replacement helps

090039 Von Duprin latch return spring for 98/99, 22, 33A/35A series: most replaced single exit device part

S-L-B Correct closer hydraulic valve adjustment sequence every time

How to Use This Guide

Each scenario below identifies a symptom, the true root cause behind it, what to check in order, and which specific part resolves it. The scenarios are organized by component type: exit devices, door closers, and lock/strike hardware.

Before replacing any part, confirm the failure is in the hardware and not in the door or frame. Door warpage, shifted hinges, building settlement, and loose door frame anchors all produce hardware symptoms that no part replacement will correct. The diagnostic steps in each scenario include checks for door and frame condition before recommending part replacement.

Exit Device Troubleshooting

Exit Device Won't Latch After the Door Closes

DiagnosisPart Replacement

What it looks like

The door closes fully against the frame but the latch bolt or vertical rod latches do not extend to engage their strikes. The door can be pushed open from the outside with no resistance. This is both a security failure and a life-safety issue if the door is fire-rated.

Check 1: Is the device dogged?

The most common cause of this symptom in a building where the device was previously functional is accidental dogging. The hex dogging key for Von Duprin 98/99 and 22/33A series takes a 5/32-inch hex wrench or dog key inserted into the dogging socket behind the push bar. If someone left the dogging key in the locked (dogged) position, the latch is held retracted. Turn the key counterclockwise to the undogged position and remove it. Cylinder dogging versions use a small cylinder key at the device mechanism case.

The dogging indicator that most technicians miss on newer Von Duprin devices: Von Duprin introduced a dogging security indicator on current production devices that provides a visual red indicator window when the device is dogged. A fully green indicator window means undogged. If the indicator shows red, the device is mechanically dogged regardless of what the key position looks like from the outside. Check the indicator before assuming the device has a failed component.

Check 2: Has the latch return spring failed?

If the device is undogged and the latch still will not extend, the latch return spring has likely failed. The return spring is the component inside the mechanism case that drives the latch bolt back to the extended (latched) position after the push bar is released. When this spring breaks or fatigues, the push bar activates the latch correctly but the latch stays retracted after the bar is released.

To confirm: depress the push bar fully, then release it. If the latch bolt does not snap back to the extended position immediately, the return spring is the failed component. On Von Duprin 98/99 and 22/33A/35A series devices, the latch return spring is part 090039: a 2-1/4 inch long, 3/8-inch diameter spring. This is the single most commonly replaced part on high-cycle Von Duprin rim devices. Browse Von Duprin exit device parts at Security Parts.

Check 3: On SVR devices, inspect rod guides

On surface vertical rod (SVR) exit devices, the vertical rod transmits push bar motion to the top and bottom latches. The rod runs along the door edge in guides mounted at intervals. If a guide shifts, loosens, or breaks, the rod can bow outward when the push bar is pressed, absorbing the motion rather than transmitting it to the top latch. The top latch then doesn't extend even if the push bar operates normally. Inspect every rod guide on the door edge for tightness and correct alignment with the rod.

The fire door latching failure that must be reported immediately: On any fire-rated door assembly where the exit device fails to latch after the door closes, the fire separation provided by that door is compromised. The door must be placed in a continuously held-closed condition and the defect must be reported immediately to the facilities manager and fire safety coordinator. This is not a condition that can wait for a scheduled maintenance visit.

Exit Device Latched But Door Opens With One Push From Outside

DiagnosisPart Replacement

What it looks like

The exit device appears to latch: the latch bolt is extended. But the door opens easily from the outside with simple push pressure, without any key or credential. This symptom indicates the latch is extending but not engaging the strike correctly.

Check 1: Latch bolt projection vs strike pocket depth

The rim latch bolt must project far enough to seat in the strike pocket (the 299 strike on Von Duprin rim devices). If the door has shifted in the frame from hinge wear, building settlement, or frame distortion, the bolt now contacts the strike face rather than entering the pocket. Close the door slowly and observe where the latch bolt contacts the strike. If it hits the face, the strike needs repositioning outward or the door needs rehinging.

Check 2: Latch bolt tip wear

The latch bolt tip on high-cycle exit devices wears down over time. The beveled tip that guides the bolt into the strike pocket becomes flat, and the bolt may contact the edge of the strike pocket rather than engaging it smoothly. A worn latch bolt can appear to latch visually (the bolt is extended into the strike area) while actually resting on the edge of the pocket without engaging. If the latch bolt tip is visibly worn flat, replace the latch mechanism. Browse exit device latch parts by series at Security Parts.

Check 3: Strike plate loose or out of position

On wood door frames in older buildings, strike mounting screws that have been repeatedly removed and reinstalled may have stripped the wood. A loose strike rocks under load from the latch bolt, allowing the bolt to appear seated while actually being held against a moving strike face. Tighten the strike screws. If the screw holes are stripped, use longer screws to reach fresh wood or use wood filler before reinstalling.

Von Duprin Dogging Key Won't Turn or Dogging Won't Hold

DiagnosisPart Replacement

Dogging key won't turn

If the hex dogging key won't turn in the dogging socket, the most common cause on older Von Duprin 98/99 and 22/33A series devices is using a key designed for pre-1997 devices on a post-1997 device, or vice versa. Post-1997 devices use the 5/32-inch hex dog key for the current dogging shaft (part 050711). Pre-1997 devices used a different dogging shaft (part 050709). The shafts are not cross-compatible. Using the wrong key type in the socket will not engage it correctly, and forcing it can damage the socket.

Also check that the push bar is fully forward (not depressed) before inserting the dogging key. The dogging hook must be in the at-rest position to engage. If the push bar has been jammed or the return spring has weakened enough that the bar rests in a partially depressed position, the dogging mechanism will not engage regardless of which key is used.

Dogging won't hold (latch extends when door closes)

If the device is dogged but the latch re-extends when the door closes, the dogging hook spring (part 090041 on 98/99 series) has failed. The dogging hook spring maintains tension on the dogging hook that holds the latch in the retracted position. A failed or fatigued spring allows the hook to release under the latch spring pressure when the door is vibrated by closing. Replace the dogging spring and the dogging hook (090044) together, as these components wear together on high-cycle devices.

The dogging restriction on fire doors that generates the most specification violations: Mechanical dogging (using the hex or cylinder key to hold the latch retracted) is specifically prohibited on fire-rated doors. A fire door must latch every single time it closes, without exception. Dogging a fire door defeats the fire separation it provides. On fire-rated openings where a hold-open or push-through function is required, electric latch retraction (EL) with a connection to the fire alarm panel is the only code-compliant method. Many building managers who dog fire corridor doors for convenience are creating a life-safety code violation that is also a liability exposure.

Door Closer Troubleshooting

Door Closer Is Dripping or Has Oil on the Body

DiagnosisReplace Unit

No valve adjustment will fix a seal failure

This is the most important troubleshooting fact for door closers: a closer dripping hydraulic oil or showing oil film on the body surface has a failed internal seal and must be replaced. The hydraulic circuit in a commercial door closer is a sealed system. Oil travels through microscopic channels inside the cylinder to regulate closing speed. When a seal fails, the circuit pressure drops and the oil eventually drains out. Turning the adjustment valves on a leaking closer changes the orifice sizes in a partially drained hydraulic circuit, which cannot restore correct operation.

Do not attempt to add oil to a commercial door closer. They are not serviceable hydraulic units in the field. The correct action is replacement with the same series and size closer. Browse LCN door closer replacement parts and cylinder assemblies at Security Parts.

How to confirm a seal failure vs surface contamination

Remove the closer cover (the plastic or metal cover over the body). Inspect the closer body surface directly. If the body surface has a wet oil film or if oil pools inside the cover, the seal has failed. If the body surface is dry and any oil is only on the cover interior without a body-surface source, check for condensation or oil from another source (such as a lubricated hinge above the closer). Condensation does not produce the characteristic oily residue of hydraulic fluid. Hydraulic fluid is typically amber to brown in color and has a distinctive petroleum smell.

The mounting screw contact that accelerates seal failure on high-traffic doors: A door closer used as a doorstop (where the door is regularly pushed or kicked open to its full stop against the closer arm rather than against a door stop) pulls the mounting screws against the closer body and creates lateral force on the spindle seal with every over-extension event. This is the most common cause of premature spindle seal failure on LCN 4040XP closers in schools, hospitals, and correctional facilities. Always install a door stop at the correct hold-open point so the arm reaches its stop position before the door does.

Door Closer Won't Close the Door All the Way

DiagnosisAdjust or Replace

Step 1: Adjust the latch speed valve (L valve)

The most common cause of a door that sweeps closed to within a few inches of the frame and then stops or drifts is latch speed set too low. The latch speed valve controls the final closing phase from approximately 15 degrees to fully closed. If this valve is too open (counterclockwise), the door loses closing force in the final phase and does not have enough momentum to compress the latch bolt against the strike. Turn the L valve clockwise in 1/4-turn increments, cycling the door two to three times after each adjustment.

Step 2: Check spring size vs door width

If latch speed adjustment doesn't resolve the failure, the spring size may be insufficient for the door. A size 3 spring on a 3-foot-6-inch door or on a parallel arm mounting (where the efficiency reduction requires one higher size) will consistently fail to close the door against even moderate HVAC or wind pressure. Increase the spring size setting by one increment and retest. On the LCN 4040XP, rotate the spring size dial clockwise to increase.

Step 3: Check for door warpage

Hold a straightedge or long level against the lock edge of the door from top to bottom. If the straightedge doesn't make continuous contact along the full height, the door is warped. Warpage exceeding 1/4 inch in a standard 7-foot door creates increasing frame resistance as the door approaches the frame, eventually exhausting the closer spring force before the latch can engage. A warped door requires attention to the door itself, not the closer. No closer adjustment compensates for significant door warpage.

Step 4: Check for HVAC stack pressure on upper floors

In multi-story buildings, HVAC pressure differentials create air pressure against fire stairwell and corridor doors, particularly on upper floors in cold weather. This pressure acts against the closer spring. If the door closes fine in summer but not in winter, stack pressure is likely the cause. Increasing the spring size by one increment typically resolves this, but verify the increased spring size does not exceed the ADA opening force limit for accessible route doors.

Door Closer Arm Bounces, Rattles or Makes Noise During Operation

DiagnosisTighten or Replace

Three connection points to check in sequence

A bouncing or rattling closer arm has loose fasteners at one of three locations. Check them in this order, tightening each before moving to the next.

1. Arm-to-spindle connection: The arm mounts to the closer body spindle (the rotating shaft that extends from the cylinder). The nut or screw securing the arm to the spindle must be tight enough to prevent rotational slip without binding arm movement. If the arm slips on the spindle during fast door motion, the arm will appear to bounce as the slip and re-engagement cycle repeats. Tighten the spindle nut to the manufacturer's specified torque.

2. Arm knuckle: The two-piece arm pivots at a center knuckle. The keeper clip or set screw at this joint must be secure. A loose knuckle allows the arm to flex at the pivot point, producing the characteristic bouncing motion particularly visible when the door is opening quickly. Secure the keeper clip or tighten the knuckle set screw.

3. Shoe-to-header fasteners: The shoe (the bracket connecting the arm to the door frame header) must be firmly fastened to the frame. On hollow metal frames, the shoe fasteners thread into the frame metal. If the frame metal has been stripped by repeated tightening, the shoe rocks under arm load. On wood frames, the shoe screw hole may be stripped. In either case, use longer or larger-diameter fasteners to reach fresh material.

If all three connection points are tight but the arm still bounces, the spindle itself may be worn, allowing lateral arm play during operation. In this case, the cylinder assembly requires replacement. Browse LCN door closer parts including cylinder assemblies at Security Parts.

Lock and Strike Troubleshooting

Commercial Door Latch Not Catching the Strike Plate

DiagnosisAdjust or Replace

Step 1: Identify where the bolt contacts the strike

Close the door slowly and watch where the latch bolt contacts the strike. The bolt should enter the strike pocket cleanly. If it contacts the strike face above or below the pocket, the strike is vertically misaligned. If it contacts the strike face to the hinge or latch side of the pocket, the strike is horizontally misaligned. Mark the contact point with lipstick or pencil chalk on the latch bolt face, close the door, and open it to see the transfer mark on the strike face. This gives you exact misalignment direction and distance.

Step 2: Adjust or move the strike

For minor vertical misalignment on wood frames, filing the strike pocket edge is sometimes sufficient. For horizontal misalignment or significant vertical shift, the strike must be repositioned. Use the Schlage 40-029 or 40-030 strike marking chisel (available at SecurityParts.com) to cut the new mortise position. Always use a template from the lock manufacturer's installation documentation when repositioning strikes to ensure the new position matches the lock's bolt projection geometry.

Step 3: Check for a failed latch spring

If the strike alignment is correct but the latch still doesn't catch, push the latch bolt manually into the door and release it. If it does not snap back firmly to full extension, the latch spring has failed. A spring latch with a fatigued spring may extend slowly or incompletely, contacting the strike face at partial extension and failing to engage the pocket. Replace the latch assembly. For Schlage ND and ALX cylindrical locks, browse the cylindrical lock parts catalog. For L Series mortise locks, browse the mortise lock parts catalog.

Step 4: Check for paint-filled strike pocket

On interior doors in commercial buildings that have been repainted multiple times, paint accumulates in the strike pocket and reduces the effective pocket depth. The latch bolt enters a partially filled pocket and cannot fully engage. This is a maintenance issue rather than a hardware failure. Clean the pocket with a chisel or pick to restore full depth. If the paint buildup is severe enough that the pocket cannot be cleaned without damaging the frame, a new strike with a deeper or larger pocket may be required.

The deadlocking plunger alignment check that most technicians skip: On locks with deadlatch function (including Schlage ND Series cylindrical locks and 16-228/16-260 deadlatches), the latch bolt alone engaging the strike pocket is not sufficient for deadlocking. The deadlocking plunger (the small secondary plunger alongside the main bolt) must contact the strike face as the door closes. If the strike is positioned too far from the door edge, the bolt enters the pocket but the plunger hangs in open air, and the door is not deadlocked even though it appears to have latched. Always verify plunger contact when adjusting or replacing strikes on deadlatch applications.

Deadbolt Not Aligning with Strike After Door Settles or Shifts

DiagnosisAdjust or Replace

What causes deadbolt misalignment after initial installation

Deadbolt strikes are positioned at installation when the door and frame are correctly aligned. Over time, three events shift the bolt position relative to the strike: hinge wear (hinge leaf wear allows the door to drop, shifting the bolt down), building settlement (frame movement shifts the strike position horizontally or vertically relative to the door), and seasonal wood movement (wood frame doors change dimension with humidity, shifting the bolt position seasonally).

How to diagnose the shift direction

Apply chalk or lipstick to the deadbolt face. Throw the bolt while the door is slightly open, then close the door carefully and release the bolt against the frame. Open the door and observe the chalk transfer mark on the door frame. The mark shows where the bolt would enter the frame if the strike were not present. Compare this to the strike pocket center. The difference in position (up, down, in, or out) is the adjustment direction needed.

For a dropped door: check and replace worn hinges first

A door that has dropped significantly has worn hinge components. Adjusting the strike to match a dropped door position provides a temporary fix that becomes incorrect again as the hinges continue to wear. Inspect the hinges first. Tight hinge leaf screws with worn hinge pins allow the door to drop without any visible screw looseness. If the hinge pin is visibly worn (showing a groove where the leaves rub), replace the hinge or the pin before adjusting the strike.

Strike adjustment options

For small adjustments within the existing mortise, file the strike pocket edge in the direction needed. For adjustments greater than 1/8 inch, the strike must be physically repositioned with a new mortise cut. For Schlage B Series deadbolt strikes including the 10-094, 10-087, and 10-116, browse the deadbolts catalog. The Schlage 40-029 strike marking chisel (for full lip strikes) and the 40-030 (for 1-1/8 inch by 2-3/4 inch strikes) allow accurate mortise cutting for strike repositioning on wood frames.

Lubricant Guide for Commercial Door Hardware

The wrong lubricant causes more long-term damage than no lubricant at all. Commercial door hardware requires specific lubricant types matched to the component material and operating environment.

Component	Correct Lubricant	Wrong Lubricant	Why Wrong is Harmful
Lock keyway and cylinder	Graphite powder or dry PTFE spray	WD-40, petroleum oil	Oil attracts dust, forms gummy paste in pin stacks, increases key wear
Latch bolt and strike pocket	Dry silicone or PTFE spray	WD-40, petroleum grease	Oil collects dust and paint particles, fills the strike pocket
Door hinges	Lithium-based or PTFE lubricant on pin and knuckle	WD-40	WD-40 is a temporary solvent; leaves residue that gums under load
Exit device mechanism	Dry lubricant (graphite or PTFE)	Oil-based lubricant	Oil in high-traffic mechanism collects contamination from corridor dust
Door closer hydraulics	None: sealed system	Any added oil or lubricant	Cannot enter sealed circuit; masks seal failure; requires replacement
Exit device push bar pivot	Light machine oil on pivot axle	Heavy grease	Heavy grease collects dust and stiffens the bar operation over time

Browse all replacement parts for Von Duprin, LCN, Schlage, Falcon, and Detex hardware at SecurityParts.com: exit devices, door closers, cylindrical locks, mortise locks, deadbolts, and electric strikes. Pre-order parts support at 845-935-0301 or the contact page.

Why Choose SecurityParts.com for Commercial Door Hardware Repair

OEM replacement parts, parts diagrams for every series, same-day shipping, and specialist diagnosis support that covers the failure mode, not just the symptom.

Failure Mode Knowledge

We document root causes, not just symptoms. The dogging indicator, deadlocking plunger alignment, latch return spring part numbers, and seal failure diagnosis are practical specialist knowledge absent from all competitor content.

OEM Part Numbers

Every part in this guide is available with its exact OEM part number. The Von Duprin 090039 latch return spring, the 050711 dogging shaft, and the 090041 dogging spring ship same day when in stock.

All Brands in One Order

Von Duprin exit device parts, LCN closer parts, Schlage lock and deadlatch parts, and Falcon hardware parts in a single order with free shipping over $450.

Same-Day Shipping

Most stocked parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for part identification and compatibility support.

What Makes SecurityParts.com Different for Troubleshooting Support

We document the Von Duprin dogging security indicator (the red/green visual window) as the first check before any component diagnosis. Most technicians bypass this and incorrectly diagnose a device as mechanically failed when it is simply dogged.
We document the fire door dogging violation: mechanical dogging of fire-rated doors is a life-safety code violation and liability exposure that is routinely performed in buildings without facilities staff understanding the restriction.
We document the closer-as-doorstop spindle seal failure mechanism. The most common cause of premature 4040XP seal failure in schools and hospitals is using the closer arm as the door stop rather than installing a correct stop. This is documented nowhere in buyer-facing closer content.
We document the deadlocking plunger contact requirement as a strike alignment check, not just a latch bolt alignment check. A deadlatch that appears latched but has the plunger hanging in open air provides no deadlocking protection.
We carry Von Duprin exit device parts, LCN door closer parts, Schlage cylindrical lock parts, mortise lock parts, and all related components for complete facility repair in one order.
Free shipping on orders over $450. Same-day shipping on stocked parts. 30-plus years of commercial door hardware experience.

Parts Quick Reference for This Guide

Scenario	Part / Action	Browse At
Exit device won't latch: return spring	Von Duprin 090039 (98/99, 22, 33A series)	Exit Device Parts
Dogging won't hold: dogging spring	Von Duprin 090041 (dogging spring) + 090044 (hook)	Von Duprin Parts
Pre/post 1997 dogging shaft	050711 (post-1997), 050709 (pre-1997)	Von Duprin Parts
Door closer oil leak	Replace full cylinder or closer unit	LCN Closer Parts
Deadbolt or latch strike repositioning: wood frame	Schlage 40-029 (full lip chisel), 40-030 (1-1/8 chisel)	All Products
Cylindrical lock latch spring failed	THP-8201 (passage) or THP-8219 (privacy) per series	Cylindrical Locks
Mortise lock deadlatch replacement	Schlage 16-228 (square corner) or 16-260 (dual option)	Mortise Lock Parts
Deadbolt strike replacement	Schlage 10-094 or 10-087 per series and grade	Deadbolt Parts

Frequently Asked Questions About Commercial Door Hardware Troubleshooting

Why does my commercial door latch not catch the strike plate?

The most common causes are strike misalignment (vertical or horizontal), a failed latch return spring (latch extends partially or slowly), or paint accumulation in the strike pocket. Apply chalk to the latch bolt and close the door to transfer-mark exactly where the bolt contacts the strike face. This shows the misalignment direction. If alignment is correct but the latch still doesn't catch, manually push and release the bolt: if it doesn't snap back firmly, the spring has failed and needs replacement. For deadlatches, also verify the deadlocking plunger contacts the strike face on closure.

Can a door closer that is dripping hydraulic oil be adjusted or does it need to be replaced?

Replace it. A leaking commercial door closer has a failed seal and cannot be repaired in the field. Valve adjustments on a leaking closer have no corrective effect because the hydraulic circuit pressure is compromised. Remove the cover to confirm: if oil is on the closer body surface rather than from an external source, the seal has failed. Replace with the same series and spring size. Do not attempt to add oil to a door closer.

Why won't a Von Duprin exit device latch after the door closes?

Check three things in order: (1) Is the device dogged? Check the dogging indicator window (red means dogged; turn the dog key counterclockwise to undog). (2) Has the latch return spring failed? Press the push bar and release it; if the latch doesn't snap back immediately, the 090039 spring needs replacement. (3) On SVR devices, inspect every rod guide for looseness or displacement that allows the rod to bow rather than transmit push bar motion to the top latch.

What causes a door closer to not fully close or latch the door?

The four causes in order of frequency: latch speed valve (L valve) set too slow for the final closing phase; spring size too small for the door width or mounting type (parallel arm needs one size higher); door warpage exceeding 1/4 inch preventing consistent frame contact; or HVAC stack pressure on upper-floor fire doors in cold weather. Adjust the L valve clockwise first. If that fails, check door straightness with a level or straightedge. Only increase spring size after confirming alignment and adjustments are correct.

What lubricant should be used on commercial door hardware?

Use graphite powder or dry PTFE spray on lock keyways and cylinders, dry silicone on latch bolts and strike pockets, and lithium or PTFE lubricant on hinge pins. Never use WD-40 on commercial door hardware: it is a temporary solvent that leaves a residue attracting dust and contaminating precision mechanisms. Never add any lubricant to a door closer: they are sealed hydraulic units. If a closer requires lubrication to function, it has a failed seal and needs replacement.

Can a fire door be dogged open with a hex key for convenience?

No. Mechanical dogging of fire-rated doors is prohibited by building codes and NFPA 80. A fire door must close and latch completely every time it closes. Dogging prevents this and compromises the fire separation the door provides, creating both a life-safety hazard and a code violation with significant liability exposure. If a hold-open function is required on a fire door, only electromagnetic hold-open connected to the building fire alarm system (such as the LCN 4040SE Sentronic, or electric latch retraction with fire alarm panel integration) is code-compliant.

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LCN Commercial Door Closer Selection Guide: Size, Mounting, ADA Compliance and Series Comparison Wednesday, July 15, 2026

Selecting the right LCN closer requires three decisions: size (1 through 6 based on door width, weight, and ADA requirements), mounting type (regular arm pull-side, parallel arm push-side, or top jamb), and series (4040XP for high-traffic and exterior; 4030 or 1000 Series for moderate interior; 2010/5010 concealed for aesthetic applications; 4040SE Sentronic for fire and smoke barrier hold-open). Interior non-fire doors on accessible routes must not exceed 5 lbs opening force (ADA Section 404.2.9). Fire doors are exempt from the 5 lbf limit. Hydraulic valves adjust in this order: S (sweep speed) first, then L (latch speed), then B (backcheck). Parallel arm mounting requires one size higher than regular arm to compensate for reduced mechanical efficiency.

Door closers generate more misspecified orders, more callbacks, and more ADA complaints than almost any other commercial door hardware component. The core reason is that three separate decisions interact: the spring size, the arm mounting type, and the series. Getting one of these wrong produces a door that either slams shut too fast, fails to latch consistently, exceeds the ADA opening force limit, or requires a complete arm change to correct. Getting all three right means the door functions correctly for years without adjustment.

Browse the complete LCN door closer parts catalog at SecurityParts.com, including parts for the LCN 4040XP, 4000 Series, 1000 Series, and concealed closer series. For pre-order selection support, call 845-935-0301 or use the contact page.

5 lbf ADA maximum opening force for interior non-fire-rated hinged doors (Section 404.2.9)

5 seconds ADA minimum sweep time from 90 degrees open to 12 degrees from latch position

+1 size Size increase required when switching from regular arm to parallel arm mounting

S-L-B Correct hydraulic valve adjustment sequence: Sweep first, Latch second, Backcheck third

How to Choose the Right Closer Size: What Sizes 1 Through 6 Actually Mean

ANSI/BHMA A156.4 defines six closer sizes based on the spring force needed to reliably close and latch a specific door. The size number is not a product generation or a quality tier. It describes the spring tension: higher numbers mean more closing force, which is needed for wider, heavier, or more exposed doors.

Size	Interior Door Width	Exterior Door Width	Typical Application	ADA Note
1	Up to 2'6"	Not recommended	Small interior utility, closet	Typically meets 5 lbf
2	Up to 2'9"	Not recommended	Light interior corridor, residential	Typically meets 5 lbf
3	Up to 3'0"	Up to 2'6"	Standard commercial interior (most common)	Verify with gauge
4	Up to 3'6"	Up to 3'0"	Heavy commercial interior, light exterior	May exceed 5 lbf; verify
5	Up to 4'0"	Up to 3'6"	Exterior entry, wind-exposed, high traffic	Exterior only; not ADA interior
6	Up to 5'0"	Up to 4'0"	Heavy exterior, institutional, vestibule	Exterior only; not ADA interior

The LCN 4040XP ships pre-adjusted to size 3 and is field-adjustable from size 1 through 6 using the green dial indicator on the closer body. This adjustability means a single closer body can serve most standard door widths, but it does not eliminate the need to verify actual opening force after adjustment. The dial position is a starting point, not a guarantee of code compliance.

The parallel arm size mistake that fails ADA on the first inspection: When a closer is mounted in parallel arm configuration, the mechanical efficiency of the arm linkage is reduced compared to regular arm. The same spring size produces less closing force in parallel arm. The correct compensation is to increase the spring size by one level above the regular arm recommendation for the same door. A door correctly sized at size 3 for regular arm mounting needs a size 4 if parallel arm is used. If the installer forgets this and installs at size 3 in parallel arm on an exterior door, the door may fail to latch in wind. If the installer overcompensates and goes to size 5, the door exceeds the ADA opening force limit on an interior application.

ADA Door Closer Requirements: Opening Force and Sweep Timing

ADA Standards Section 404.2.9 sets two requirements for door closers on accessible routes.

The 5 lbf Opening Force Rule

Interior hinged, sliding, or folding doors that are not fire-rated must require no more than 5 pounds-force to open when measured at the door handle or push face. This force is measured perpendicular to the door from a fully closed and latched position. The measurement point matters: measuring from the hinge edge produces a lower force reading than the handle edge, but the ADA measurement is at the door face closest to the latch side. Peak force is what counts, not average force.

Exterior doors are not subject to the federal 5 lbf cap, but most state codes and ANSI A117.1 set a limit of 8.5 lbf for exterior accessible entrances. Check your state's specific code before assuming exterior doors have no opening force limit.

The spring size that complies on paper but fails in winter: A closer adjusted to produce 4.8 lbf in September will frequently produce 6 to 7 lbf in January in cold-climate buildings. Hydraulic closer fluid thickens as temperature drops, increasing the resistance of the sweep valve even without any adjustment change. A closer that barely meets the 5 lbf limit in warm conditions will violate it in winter. The correct practice is to measure opening force during the coldest typical weather for the building and set the spring size to meet ADA at that measurement point. A force gauge measurement in summer alone is insufficient for year-round compliance verification.

Fire Door Exception

Fire-rated doors are explicitly exempt from the 5 lbf opening force limit because fire doors must close and latch against their door seals with enough force to maintain the fire and smoke separation under elevated temperature conditions that cause door frame expansion. A fire door closer adjusted to 5 lbf may fail to latch against a swollen frame during a fire event. This is why fire stairwell doors and fire corridor doors feel harder to push open than standard commercial doors. That is not a defect and not a code violation. It is the required performance level for fire-rated assemblies.

The 5-Second Sweep Timing Requirement

ADA also requires that a door closer allow the door to travel from a 90-degree open position to within 12 degrees of the latch in at least 5 seconds. This minimum time allows a person using a wheelchair, walker, or crutches to clear the door opening before the door closes on them. The S valve (sweep speed valve) controls this motion. Setting the S valve too fast (closing the door quickly) violates this requirement even if the opening force is within limits. Both requirements must be met simultaneously.

Arm Mounting Types: Regular, Parallel, and Top Jamb

Regular Arm (Hinge Side Mount)

Regular arm mounting places the closer body on the pull side of the door at the hinge side of the door face. The arm connects the closer body to the door frame at the header. This is the default, most mechanically efficient mounting position. The arm alignment is optimized so the full spring force is applied to the door through a direct mechanical path. Regular arm is the correct first choice for any door where it is physically possible.

The LCN 4010 is specifically designed for regular arm pull-side mounting and uses a mounting hole pattern of 2-1/2 inches vertical by 6 inches horizontal (center to center). The 4040XP uses a staggered pattern of 2-1/4 inches vertical by 5 inches horizontal. These patterns are not interchangeable: a 4010 arm will not bolt to a 4040XP body or vice versa.

Parallel Arm (Push Side Mount)

Parallel arm mounting places the closer body on the push side of the door with the arm running parallel to the door frame when the door is closed. The closer mounts at the top rail of the door, and the shoe (the bracket at the end of the arm) mounts to the door frame head. The arm swings out as the door opens, positioning parallel to the frame at full close.

Parallel arm is used when the closer must be on the push side (where the hinge side of the door is inaccessible or when the specification requires the closer not to be visible from the pull side corridor). It is also the preferred mounting for wide vestibule doors where the arm geometry works more cleanly in parallel configuration. The mechanical efficiency reduction in parallel arm requires one size larger spring than regular arm for the same door.

The LCN 4110 series is dedicated to parallel arm push-side mounting. The 4040XP includes a parallel arm shoe (4040XP-62PA) as part of its tri-pack to accommodate parallel arm mounting on the universal body.

Top Jamb (Frame Head Mount)

Top jamb mounting places the closer body on the door frame head (the top of the frame) rather than the door itself. The arm extends from the closer body down to the door face. This mounting is required on glass storefront applications where the door top rail is too narrow to mount a closer body, and on narrow-profile aluminum frame doors where the door rail depth does not accommodate a surface closer.

Top jamb has more geometric limitations than the other mounting types: the frame head reveal depth, the ceiling height above the frame, and the door swing angle all affect arm selection and mounting plate requirements. The LCN 4020 series is specifically designed for top jamb push-side mounting. The 4040XP requires the 4040XP-18TJ plate for top jamb mounting when the head frame reveal is less than 3-1/2 inches.

LCN Closer Series Comparison: Which Series for Which Door

LCN 4040XP

Heavy Duty | Size 1 to 6 | Tri-Pack Universal

The industry benchmark for high-traffic, exterior, institutional, and abuse-prone openings. Cast iron cylinder, forged steel arm, double heat-treated pinion, full complement low-friction bearings. Non-PRV (pressure relief valve) design. Size 1 to 6 adjustable via green dial. Tri-pack covers regular, parallel arm, and top jamb from one unit. Interior doors to 5 feet wide, exterior to 4 feet wide. 30-year warranty.

LCN 4010 / 4020 / 4110

Single-Mount Dedicated | 4000 Series Bodies

Dedicated-mount versions of the 4000 Series using the same heavy-duty body as the 4040XP but packaged for a single mounting position. 4010: regular arm pull side. 4020: top jamb push side. 4110: parallel arm push side. Different mounting hole patterns from the 4040XP. Specified when only one mounting type is needed and the project does not require tri-pack versatility.

LCN 4030

Universal Mid-Range | Regular, Parallel, Top Jamb

A mid-range universal closer for moderate traffic interior and exterior applications. Covers regular arm, parallel arm, and top jamb from one unit. Fully adjustable closing speeds and backcheck. Compact and cost-effective versus the 4040XP for office suites, moderate corridors, and standard commercial interior openings where full institutional-grade construction is not required.

LCN 1000 Series

Slim Profile | Light to Moderate Traffic | Interior

Slim profile closer for interior doors in lower-traffic environments including offices, classrooms, and hotel corridors. Same arm control options as the 4000 Series. Ships without cover as standard (optional plastic or metal covers available). Same finish options as 4000 Series. Specified when the door is interior, moderate traffic, and full 4040XP institutional grade is not required. Significant cost advantage on large interior-only projects.

LCN 4040SE Sentronic

Fire and Smoke Barrier | Electromagnetic Hold-Open

4040XP body with an integrated electromagnetic hold-open coil that connects to the building fire alarm system. Holds fire and smoke barrier corridor doors open during normal building operations and releases them automatically when the fire alarm panel activates, allowing the door to close under spring force. Required on fire-rated and smoke barrier doors where hold-open function is needed without a separate wall-mounted electromagnetic holder.

LCN 2010/5010 Concealed

Head Frame Concealed | Aesthetic Applications

Concealed overhead closers with the cylinder housed in the door frame head and the arm and track concealed in the door top rail. Provides a completely clean appearance with no visible hardware on either door face. Specified in lobbies, courtrooms, executive corridors, and high-end retail where visible surface closers are architecturally unacceptable. Higher installation cost and requires correct frame and door top rail dimensions. Parts covered in the SecurityParts.com LCN concealed closer catalog.

The Non-PRV Design: Why It Matters on the 4040XP

PRV stands for pressure relief valve, a safety valve found in some door closer hydraulic systems that releases pressure if the hydraulic circuit is overloaded. On closers with PRV design, an impact event (a door being kicked open or slammed by wind) can trigger the PRV, releasing hydraulic fluid and causing the closer to lose its adjustment. The closer then requires re-adjustment and can potentially develop a permanent hydraulic leak through the relief valve pathway.

The LCN 4040XP uses a non-PRV design. The hydraulic circuit is sealed without a pressure relief pathway, and the closer body is built with sufficient structural strength to absorb impact forces without requiring a pressure relief mechanism. The result is a closer that maintains its adjustment setting after abuse events and does not develop PRV-related hydraulic fluid loss. This is one of the most significant durability differences between the 4040XP and lower-cost commercial closers that use PRV design to reduce manufacturing costs.

How to tell if a hydraulic leak is from a failed seal versus a PRV bleed: A failed hydraulic seal on a door closer produces a slow, expanding oil stain on the closer body surface, typically appearing first around the arm spindle. A PRV bleed on a closer with PRV design produces a specific drip point at the relief valve location on the body. On a non-PRV closer like the 4040XP, hydraulic leaks are almost always seal failures rather than PRV events and indicate a specific failed seal rather than a systemic pressure control issue. Knowing which type of leak is present tells the service technician whether to order a seal kit or a cylinder assembly replacement.

How to Adjust LCN Door Closer Hydraulic Valves

LCN surface closers have three hydraulic adjustment valves, and the order of adjustment matters because each valve's setting affects the motion the next valve must control. Adjusting out of sequence wastes time and produces settings that interact with each other in ways that are difficult to diagnose.

S Valve: Sweep Speed First

The S valve controls the main door travel from fully open (90 degrees) to approximately 10 to 15 degrees before the latch position. Set this so the door closes in 5 to 7 seconds from 90 degrees for interior doors, and 4 to 6 seconds for exterior doors. Clockwise rotation slows the sweep. Counterclockwise speeds it up. The ADA minimum of 5 seconds applies from 90 degrees to 12 degrees from the latch on accessible routes. Set S first because latch speed and backcheck both interact with the position at which sweep ends.

L Valve: Latch Speed Second

The L valve controls the door movement from the point where sweep ends (approximately 15 degrees from latch) to the fully closed and latched position. This is the last phase of closing. Too fast produces an audible slam that annoys occupants and stresses the latch mechanism. Too slow causes the door to drift toward closed without positive latching, particularly against weatherstripping resistance. Adjust for a smooth, firm close that audibly latches without slamming. Clockwise slows latch speed.

B Valve: Backcheck Third

Backcheck controls the resistance the closer applies when the door is pushed past approximately 70 to 75 degrees of opening. It prevents the door from slamming fully open against a wall stop, which damages the door, frame, and closer arm. Clockwise increases backcheck resistance. Engage backcheck on all exterior doors exposed to wind and on any door where someone could push it hard enough to hit the wall. Interior low-traffic doors may not need backcheck engaged. Set B last because backcheck position only matters after sweep and latch speeds are established.

The seasonal re-adjustment that most facilities skip and then blame on a failed closer: LCN hydraulic closers use oil-based hydraulic fluid. Like all hydraulic fluids, it thickens at lower temperatures and thins at higher temperatures. A closer adjusted to correct sweep and latch speeds in October will be noticeably slower in January in a northern climate building, especially on doors with vestibule stack pressure. Facilities that record ADA complaints about heavy or slow doors in winter often have closers that were correctly adjusted in summer but were never re-verified in cold weather. The correct maintenance practice is to check and adjust sweep speed and opening force twice a year: once in early summer and once in mid-winter. This is a 5-minute adjustment per door, not a repair event.

Fire Door Closer Requirements

Closers on fire-rated door assemblies have requirements beyond standard commercial applications. Every fire door must return to a fully closed and latched position automatically after each use, without exception. This requirement eliminates all free-swing and permanent hold-open configurations on fire-rated openings unless the hold-open device is an electromagnetic unit connected to the fire alarm system that releases on alarm.

Spring Size on Fire Doors

Fire doors require sufficient spring force to close against their seals under conditions where the door frame may have expanded slightly from heat exposure. A fire closer set to minimum spring size to meet ADA may produce a door that closes perfectly under normal conditions but fails to latch against an expanded frame during a fire event. Fire door closers should be set to a spring size that provides positive latching against the full compression of the door seals, even if this exceeds the 5 lbf ADA limit. The ADA fire door exemption exists precisely for this reason.

LCN 4040SE Sentronic for Hold-Open

When fire door corridor doors must be held open during normal building operations (for air circulation, visual supervision, or traffic flow) but must close on alarm, the LCN 4040SE Sentronic integrates the closer and electromagnetic hold-open in a single unit. The electromagnetic coil holds the door open during normal operation. When the fire alarm panel activates, current interruption to the coil releases the door and the spring drives it to closed and latched position. No separate wall-mounted electromagnet is required. The Sentronic is the correct specification for fire door hold-open applications and is available with the full 4040XP heavy-duty closer body.

Browse the complete LCN door closer parts catalog at SecurityParts.com. For specific series part numbers and diagrams, browse the LCN parts catalog by series. For related commercial door hardware, browse Von Duprin exit device parts, Schlage L Series mortise lock parts, and the complete all products and parts catalog.

Why Choose SecurityParts.com for LCN Door Closer Parts

Non-PRV design explanation, seasonal re-adjustment warning, parallel arm size correction, winter compliance failure, and same-day shipping on stocked LCN parts.

Non-PRV Design Detail

We document the 4040XP non-PRV design and explain how to distinguish PRV bleed leaks from seal failures. No other parts supplier documents this at the product ordering stage.

Seasonal Compliance Warning

We document that closers adjusted to ADA compliance in summer frequently violate the 5 lbf limit in winter due to hydraulic fluid thickening. Winter-only ADA complaints are almost always a seasonal re-adjustment issue, not a failed closer.

Parallel Arm Size Correction

We document the one-size increase required for parallel arm mounting. Installers who skip this step produce doors that fail to latch in wind on exterior openings or exceed ADA limits on interior accessible routes.

Same-Day Shipping

LCN 4040XP, 4000 Series, 1000 Series, and concealed closer parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for series and size confirmation.

What Makes SecurityParts.com Different for LCN Door Closer Parts

We document the seasonal hydraulic fluid thickening issue that produces winter ADA compliance failures on closers correctly adjusted in summer. This is the most common cause of winter ADA door complaints in commercial buildings and is documented nowhere in standard specification content.
We document the non-PRV design of the 4040XP and explain how to diagnose PRV bleed leaks versus seal failures. This diagnostic detail prevents unnecessary cylinder replacements when the real issue is a specific seal failure.
We document the parallel arm size increase requirement and explain why parallel arm mounting reduces mechanical efficiency. Installers who miss this produce either latching failures or ADA violations depending on which direction they err.
We document the fire door spring size conflict with ADA: fire doors are exempt from the 5 lbf limit and should be set above this threshold for reliable latching against expanded frames during fire conditions.
We carry all LCN door closer replacement parts across the complete LCN parts catalog alongside Von Duprin exit device parts, electric strike parts, and cylindrical lock parts for full commercial door hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

LCN door closers appear on every commercial door alongside locks, exit devices, and access control hardware. Most service calls cover multiple components simultaneously.

For Von Duprin exit device parts on fire-rated corridor doors in the same building as LCN closers, browse the exit devices catalog. For Von Duprin electric strike parts on access-controlled openings that also carry LCN closers, browse the electric strikes catalog. For Schlage L Series mortise lock parts on main entries with LCN 4040XP or Sentronic closers, browse the mortise locks catalog. For ND Series cylindrical lock parts on corridor doors with LCN 4000 or 1000 Series closers, browse the cylindrical locks catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About LCN Commercial Door Closer Selection

What do the door closer size numbers 1 through 6 mean and how do I choose the right one?

Sizes 1 through 6 describe spring force: size 1 is lightest for small interior doors, size 6 is heaviest for wide exterior doors in high wind. Standard interior commercial doors (3 feet wide) typically need size 3 or 4. Exterior doors start at size 4 or 5. When using parallel arm mounting, increase by one size. The LCN 4040XP ships at size 3 and is field-adjustable via green dial. Always verify opening force with a calibrated gauge after adjustment to confirm ADA compliance.

What is the ADA opening force limit for door closers and which fire door exception applies?

ADA Section 404.2.9: interior non-fire-rated hinged doors must open with no more than 5 pounds-force. ADA also requires at least 5 seconds for door travel from 90 degrees to 12 degrees from the latch. Exterior doors are not subject to the federal 5 lbf limit but most states cap them at 8.5 lbf under ANSI A117.1. Fire-rated doors are explicitly exempt from the 5 lbf limit because fire doors need sufficient spring force to latch against seals under elevated temperature conditions.

What is the difference between regular arm, parallel arm, and top jamb door closer mounting?

Regular arm mounts the closer on the pull side at the hinge side of the door. Most mechanically efficient. Parallel arm mounts on the push side with the arm parallel to the frame when closed. Requires one size larger spring to compensate for reduced efficiency. Top jamb mounts the closer body on the frame head with the arm extending to the door face. Used on glass storefronts and narrow-rail aluminum doors where door-mounted closers will not fit.

What is the difference between the LCN 4040XP and the LCN 4010, 4020, and 4110 series?

The 4040XP is a universal tri-pack covering regular arm, top jamb, and parallel arm from one body, with a staggered hole pattern (2-1/4 inch by 5 inch center to center). The 4010 is regular arm pull-side only with a 2-1/2 inch by 6 inch hole pattern. The 4020 is top jamb push-side, same body as 4010. The 4110 is parallel arm push-side. Specify the 4040XP when a single universal body is needed across a project; specify the 4010/4020/4110 for dedicated single-mount installations where the different hole pattern is acceptable.

What is the correct order to adjust the hydraulic valves on an LCN door closer?

Always adjust S (sweep speed) first, then L (latch speed), then B (backcheck). Set S so the door closes from 90 degrees to near-latch in 5 to 7 seconds interior (5 seconds minimum for ADA). Then set L for smooth firm latching without slamming. Then set B for door opening resistance past 70 to 75 degrees. Cycle the door two to three times after each adjustment because hydraulic response lags before stabilizing. Re-check and re-adjust in winter as hydraulic fluid thickens in cold temperatures.

When should an LCN 1000 Series closer be specified instead of the 4040XP?

The LCN 1000 Series is appropriate for interior, moderate-traffic doors in offices, classrooms, and hotel corridors where the full institutional-grade construction of the 4040XP is not required. It ships without a cover as standard and has a slimmer profile. The 4040XP is the correct specification for high-traffic, exterior, institutional, abuse-prone, and fire-rated applications. On large interior-only projects, specifying 1000 Series for interior doors and 4040XP for perimeter and high-use openings is the cost-effective approach.

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Falcon M Series, Von Duprin 283, LCN 2610 Cylinder and Schlage Trim Accessories Parts: Complete Guide Tuesday, July 14, 2026

Security Parts carries specialty and accessory parts that keep complete commercial door hardware systems functioning: the Falcon 030057-002 M Series lever return spring for older Falcon MA mortise lock lever trim (Avalon, Dane, Quantum, Sutro designs), the Falcon 005099-000-30 ANSI dust box (1-inch deep) for hollow metal frame strike applications, the Von Duprin 283 vertical rod top strike for wood frame installations with 33A/35A/98/9947 series exit devices, the LCN 2613-3071 and 2614-3071 standard cylinder assemblies for the 2610 pneumatic Auto Equalizer multi-door operator, and Schlage trim accessories including privacy roses (09-459 C design, 09-486 B design), trim collar 36-031, trim ring and security insert 36-071, and diameter adapter ring 38-031.

The commercial door hardware parts that generate the most confused orders are not the major assemblies. They are the specialty components and accessories that service technicians need when a single part fails on an otherwise functional system. A lever that droops on an older Falcon mortise lock needs a specific return spring. A vertical rod exit device on a wood frame needs a specific top strike that does not ship with the device for metal frame applications. A door with a bore that does not match the lock requires an adapter ring rather than a new door bore. These parts exist precisely for field service situations, and every one of them is available at SecurityParts.com.

Browse the complete Schlage, Falcon, Von Duprin, and LCN parts catalog at Security Parts. For the lock series these accessories serve, browse Falcon hardware parts, Von Duprin exit device parts, and LCN door closer and operator parts.

Yellow Color of the 030057-002 replacement spring (replaces older green springs in M Series)

1" deep Falcon 005099 ANSI dust box depth for full ANSI deadbolt throw accommodation

Wood frame Von Duprin 283 top strike is specifically for wood frame (not hollow metal) SVR installations

Multi-door LCN 2610 Series is the pneumatic multi-door solution; 2613/2614 are its size 3/4 cylinders

Falcon M Series Lever Return Spring: Part 030057-002

The Falcon 030057-002 is the lever return spring for older Falcon M Series mortise lock lever trim. Understanding what "M Series" means in this context is important: the MA Series (currently produced Falcon Grade 1 mortise lock) replaced the earlier M Series, and the 030057-002 spring serves the older pre-MA lever trim designs rather than current production MA mortise locks.

What the Return Spring Does

The return spring is the torsion spring inside the lever trim assembly that returns the lever to its neutral horizontal position after a person rotates the lever to retract the latch bolt. Without a functional return spring, the lever drops to a downward angle after operation and stays there rather than returning to horizontal. This drooping lever is visible to anyone approaching the door and indicates that the spring has failed. It can also cause incomplete latch retraction if the lever position affects the latch cam alignment.

Spring Color: Yellow Replaces Green

The 030057-002 replacement spring is yellow in color. It replaces the older green spring that was used in earlier M Series production. When a technician disassembles an older Falcon M Series lever trim and finds a green spring, the replacement is the yellow 030057-002. The color change indicates a material or specification update in the spring while maintaining fit compatibility with the original lever trim designs.

Lever Designs This Spring Serves

The 030057-002 serves the Avalon, Dane, Quantum, and Sutro lever designs in the Falcon M Series product line. These are named lever style designations from the older Falcon catalog. When confirming the spring is the correct part for a specific installation, check the lever style name stamped or labeled on the trim escutcheon or the Falcon catalog page for the original installation. If the lever design name is one of these four, the 030057-002 is the correct replacement spring.

The limited availability warning on the 030057-002 spring: The Falcon M Series lever return spring is noted as a limited availability item because the M Series product line is older and no longer in active production. Parts are sourced from remaining stock. When a facility has multiple Falcon M Series mortise locks in the same building, ordering spare 030057-002 springs while they are available is the correct approach. When stock is exhausted, the only service option for a failed M Series lever trim is complete lever trim replacement with current MA Series trim, which may require chassis compatibility verification.

Falcon 005099-000-30 ANSI Dust Box

The Falcon 005099-000-30 is a separate ANSI dust box with 1-inch depth for Falcon lock strike applications on hollow metal frames. The product number suffix -30 indicates aluminum finish for the box housing.

Why a Separate Dust Box Is Sometimes Needed

Most commercial door hardware ships with strike plates that include an integrated box. However, there are field situations where a separate box is required. When a strike plate is damaged and replaced with a flat no-box strike on a hollow metal frame, a separate dust box must be added to provide the bolt cavity the metal frame cannot provide on its own. When the original box is damaged or corroded but the strike plate face is still serviceable, a replacement box can restore the installation without replacing the full strike. The Falcon 005099 is the separate box component that addresses these situations in Falcon cylindrical and mortise lock applications.

ANSI Dimensions and Depth

ANSI specification dust boxes follow the ANSI/BHMA A156.31 standard for strike dimensions. The 1-inch depth of the 005099 accommodates the full throw of an ANSI-specification deadbolt (typically 1-inch throw) without the bolt hitting the back of the box before fully extending. Using a box that is too shallow prevents the bolt from fully extending, which can be mistaken for a close-out or cylinder adjustment problem when the real issue is the box depth.

The too-shallow box that looks like a latch alignment problem: A dust box whose depth does not accommodate the full bolt throw prevents the latch or deadbolt from fully extending on door closure. The door appears to latch or deadlock but the bolt is not fully extended. This creates a door that can be opened with less force than a fully latched door because the bolt is only partially engaged in the strike pocket. On ANSI-specification Grade 1 applications, using the correct 1-inch deep box ensures the full 1-inch bolt throw is accommodated.

Von Duprin 283 Vertical Rod Top Strike

The Von Duprin 283 is a vertical rod top strike specifically for wood frame installations with the Von Duprin 33A, 35A, 98, and 9947 series surface vertical rod exit devices. Understanding what a vertical rod top strike does and why the frame material determines which strike is required is essential for correct ordering on any SVR exit device installation.

How Vertical Rod Exit Devices Work at the Top

A surface vertical rod exit device has two latch points: the main latch bolt that engages a strike in the door frame at the standard latch height, and a top latch that travels up a vertical rod to a strike mounted in the door frame header at the top of the door. When the push bar is pressed, both latch points release simultaneously. The door cannot be fully secured unless both strikes are correctly installed and aligned with their respective latches.

On hollow metal door frames in commercial construction, the top strike is typically embedded into the hollow metal frame construction during manufacturing, or is a separate component that mounts in the hollow metal header section. The 283 is specifically the wood frame version: it is the separate top strike component that mounts into the wooden header of a wood frame application where no integrated top strike exists.

Series Compatibility

The Von Duprin 283 serves the 33A, 35A, 98, and 9947 series SVR (surface vertical rod) exit devices in wood frame applications. The WDC (wood door construction) designation on these series indicates the wood frame version of the device, and the 283 is the standard top strike for WDC installations. The 283 is not the correct top strike for hollow metal frame applications, where a different strike component is used to match the frame construction.

The top latch that does not engage when the 283 is missing or misaligned: A Von Duprin SVR exit device on a wood frame where the 283 top strike is missing or mispositioned latches only at the bottom latch. The top latch rod has nowhere to engage and the device appears to function (push bar operates correctly) but the door is not secured at the top. This single-point latching creates a door that can be pushed open at the top even when the lower latch is engaged. On fire-rated door assemblies, single-point latching may not meet the latching requirement for the fire assembly. Always confirm the 283 top strike is installed and aligned with the top latch during any SVR device service call on wood frames.

Installation Notes for the Von Duprin 283

The 283 is installed in the door frame header during exit device installation. The top latch rod is cut to the correct length during installation (most SVR devices require rod cutting for doors shorter than 7 feet). The 283 strike must be positioned at the correct height to align with the fully extended top latch position. Incorrect height positioning of the 283 produces either a top latch that misses the strike pocket (too high or low) or a top latch that contacts the strike face before fully extending (too far out). Template-based positioning, using the manufacturer's installation instructions, prevents all three alignment errors.

LCN 2613-3071 and 2614-3071 Cylinder Assemblies

The LCN 2613-3071 and 2614-3071 are standard cylinder assemblies for the LCN 2610 Series pneumatic Auto Equalizer operator. The 2610 Series is the only pneumatic multi-door automatic operator in the LCN catalog, designed to provide low-energy automatic door opening assistance on multiple doors connected to a single compressed air supply.

Understanding the 2610 Pneumatic Auto Equalizer

The LCN 2610 is distinct from all other LCN automatic operators in one important way: it uses compressed air rather than electromechanical or electrohydraulic power to open doors. A single air supply unit and compressor can power multiple 2610 operator cylinders throughout a corridor or building section, making the 2610 the cost-effective choice for multi-door automatic opening projects where running individual electrical connections to each door would be prohibitively expensive.

The cylinder assembly is housed in the head frame (concealed in the frame) with the arm and track concealed in the door top rail. The 2610 provides manual opening up to 90 degrees of powered opening and up to 160 degrees of manual opening. The 10,000,000 cycle heavy-duty cylinder is sized to match the 2010 Series overhead concealed closer in durability.

Cylinder Assembly Size Numbers

The 2613-3071 is the size 3 cylinder assembly for exterior doors to 30-inch width and interior doors from 30 to 38 inches. The 2614-3071 is the size 4 cylinder assembly for larger door widths. The size number in the cylinder assembly part number corresponds to the spring force needed for the specific door width, following the same sizing convention used across the LCN closer catalog.

Handing must be specified when ordering. The -3071 suffix indicates the standard aluminum finish cylinder. Left hand (LH) and right hand (RH) versions are available. Handing on the 2610 is determined by the cylinder orientation in the head frame, which is set at installation for the specific door swing direction.

The pneumatic system diagnosis that most technicians miss on 2610 installations: When a 2610 operator begins providing inconsistent or weak opening force on one door in a multi-door system, most technicians first diagnose the cylinder assembly. The actual cause is frequently not the cylinder but the pneumatic supply pressure or a restriction in the air line serving that specific operator. The 2610 requires adequate air pressure from the compressor and control box. A clogged air line fitting, a kinked supply tube, or a failing control box valve produces the same symptom as a cylinder failure. Confirm air pressure at the cylinder supply port before ordering a cylinder assembly replacement.

When the Cylinder Assembly Requires Replacement

The 2613-3071 and 2614-3071 cylinder assemblies require replacement when the cylinder develops an internal hydraulic fluid leak (producing erratic or uncontrolled door movement despite correct air pressure), when the piston seal fails (causing loss of opening force that is not resolved by checking air supply pressure), or when the cylinder body is physically damaged from impact or severe weather exposure. The 2610 cylinder is rated for 10,000,000 cycles, which translates to a very long service life in typical commercial applications, so cylinder assembly failure is less common than air supply or control box failures.

Schlage Trim Accessories

Schlage produces a range of trim accessories that address specific field situations in cylindrical lock, tubular lock, and mortise lock installations. These are not the primary lock components but the supporting trim and interface components that make installations cleaner, more secure, or compatible with non-standard door preparations.

Schlage 09-459 and 09-486 Privacy Roses

The Schlage 09-459 is the C design privacy rose and the 09-486 is the B design privacy rose, both for Schlage LT Series and related tubular lock families. The rose is the decorative plate that covers the bore preparation area and the lock chassis mounting points on both sides of the door, providing a finished appearance and preventing debris accumulation around the bore edge.

Privacy roses are specifically designed for the privacy function (the push-button or thumbturn lock function used on bathroom and bedroom doors) where the rose design incorporates the visual language of privacy hardware in the building's overall hardware aesthetic. The C and B designations refer to the design family of the rose profile, which must match the lever style being used for visual consistency. Using the wrong rose design in a building with a consistent lever specification produces a mismatched appearance that is aesthetically unacceptable on completed projects.

Schlage 09-459 Privacy Rose, C Design

LT Series | C Design Profile

Privacy rose in C design profile for Schlage LT Series and related tubular lock families. Replaces damaged or finish-mismatched roses on existing installations. Confirm C design matches the lever style installed on the same door before ordering. Match finish to existing hardware.

Schlage 09-486 Privacy Rose, B Design

LT Series | B Design Profile

Privacy rose in B design profile for Schlage LT Series and related tubular lock families. The B design has a different edge and surface profile from the C design and is paired with specific lever styles. Always verify the design letter matches the lever design before ordering a replacement rose.

Schlage 36-031 Trim Collar

The Schlage 36-031 trim collar is used to cover oversized bore preparations or cosmetic damage around a bore hole that is larger than the standard rose footprint. In renovation projects or repair situations where the existing bore has been enlarged by previous hardware installation (particularly when a door has had multiple different lock installations over its lifetime), the bore edge may be chipped, worn, or oversized. The trim collar mounts over the bore and provides a clean finished edge that the rose can sit against, concealing the irregular bore condition.

The 36-031 is also used in CL Series cabinet lock and related applications where a trim collar provides the interface between the lock body and the door or cabinet face panel. For commercial cabinet and locker installations, the 36-031 provides a finished edge presentation that matches the hardware finish rather than exposing the raw bore edge.

Schlage 36-071 Trim Ring and Security Insert Pack

The Schlage 36-071 trim ring and security insert pack provides two components in one package. The trim ring is the decorative ring that mounts on the door face around the bore, providing a finished appearance. The security insert is a reinforcing component that fits inside the trim ring and prevents the lock chassis from being pulled through the door in a forcible entry attempt.

The security insert addresses a specific vulnerability in cylindrical lock installations: without a security insert, a determined forced entry attempt can apply sufficient force to pull the entire lock chassis body through the door bore from the outside, exposing the interior latch mechanism. The security insert creates a mechanical stop that prevents this pullthrough even when significant force is applied. On exterior doors in high-risk applications, specifying the 36-071 with security insert as part of every cylindrical lock installation adds meaningful resistance to this attack vector at minimal cost.

The pullthrough attack that the security insert prevents: Commercial cylindrical locks in standard trim are vulnerable to a forcible entry technique where high impact force is applied directly to the lock trim in an outward direction, attempting to pull the chassis body through the bore hole. Without a security insert, the chassis trim is held only by mounting screws and the natural friction of the bore fit. On hollow-core commercial doors with worn bore edges, this attack can succeed. The 36-071 security insert creates a larger bearing surface that cannot pass through the bore hole regardless of the impact force, effectively blocking this attack. The insert is an inexpensive addition that significantly increases forced entry resistance without requiring hardware replacement.

Schlage 38-031 Diameter Adapter Ring for 2-1/8-Inch Door Prep

The Schlage 38-031 is a diameter adapter ring for 2-1/8-inch door bore preparations. The standard commercial cylindrical lock bore is 2-1/8 inches in diameter. Some door configurations, particularly in certain residential-to-commercial conversions and renovation work, may have bore preparations that are slightly different from this standard. The adapter ring corrects the bore interface without requiring re-boring the door, which would require special tools and extend the service time significantly.

The 38-031 is also used in specific Schlage S Series and CS210 mounting configurations where the mounting geometry requires the adapter ring to correctly space the trim from the door face. When an installation produces visible gaps around the rose or trim plate that suggest a bore diameter mismatch, checking for the 38-031 as the correct correction component resolves the issue without door work.

Complete Parts Reference

Part Number	Description	Series	Key Ordering Note
Falcon 030057-002	M Series lever return spring (yellow replaces green)	Falcon MA/M Series mortise (older)	Limited availability. Fits Avalon, Dane, Quantum, Sutro levers only.
Falcon 005099-000-30	ANSI dust box, 1-inch deep	Falcon cylindrical and mortise lock strikes	For hollow metal frames. 1-inch depth required for full ANSI bolt throw.
Von Duprin 283	Vertical rod top strike for wood frames	Von Duprin 33A, 35A, 98, 9947 SVR	Wood frame only (WDC designation). Not for hollow metal frames.
LCN 2613-3071	Standard cylinder assembly, size 3	LCN 2610 pneumatic Auto Equalizer	Specify LH or RH handing. Exterior doors to 30 inch, interior 30 to 38 inch.
LCN 2614-3071	Standard cylinder assembly, size 4	LCN 2610 pneumatic Auto Equalizer	Specify LH or RH handing. Larger door widths than size 3.
Schlage 09-459	Privacy rose, C design	Schlage LT Series and related tubular	Must match lever design letter (C) for correct aesthetic pairing.
Schlage 09-486	Privacy rose, B design	Schlage LT Series and related tubular	Must match lever design letter (B). Not interchangeable with C design.
Schlage 36-031	Trim collar	Cylindrical locks, CL Series cabinet	Used for oversized or damaged bore edges; CL cabinet lock interface.
Schlage 36-071	Trim ring and security insert pack	Schlage cylindrical locks	Security insert prevents chassis pullthrough on exterior doors.
Schlage 38-031	Diameter adapter ring for 2-1/8-inch door prep	Cylindrical locks, CS210, S Series	Corrects bore size mismatch without re-boring door.

Why These Parts Matter More Than They Appear To

The parts in this guide are not the primary lock bodies or major assemblies. They are the components that determine whether a major assembly installation is complete, secure, and professional. A Von Duprin SVR device installed without the 283 top strike on a wood frame provides single-point latching that fails to secure the door at the top. A cylindrical lock installed without the 36-071 security insert on an exterior door has a vulnerability that the lock body's ANSI Grade 1 rating does not address. A Falcon M Series mortise lock with a failed return spring presents a lever that hangs at an angle and may not fully function, making the lock appear broken when only a small spring has failed.

Every one of these parts represents a service opportunity: diagnosing the correct accessory part rather than replacing a complete assembly saves significant cost for the facility while restoring full function. SecurityParts.com stocks all of these components for same-day shipping.

Browse the complete Falcon, Von Duprin, LCN, and Schlage parts catalog at SecurityParts.com. For the lock series these accessories serve, browse Schlage L Series and Falcon MA mortise lock parts, Von Duprin and Falcon exit device parts, LCN door closer and operator parts, and Schlage ND Series cylindrical lock parts. Pre-order support at 845-935-0301 or the contact page.

Why Choose Security Parts for These Specialty Parts

Spring color change documentation, 283 wood vs metal frame distinction, pneumatic air supply diagnosis first, security insert pullthrough prevention, and same-day shipping.

M Series Spring Detail

We document that the 030057-002 yellow spring replaces the older green spring, and specify the four lever designs it fits. Without this detail, technicians cannot confirm the part without disassembling the trim to check the spring color.

283 Frame Distinction

We document that the Von Duprin 283 is specifically for wood frame installations. Installing a hollow metal frame top strike on a wood application or omitting the 283 on wood frames produces single-point top latching that fails to secure the door header.

Security Insert Value

We document the pullthrough attack vulnerability that the Schlage 36-071 security insert prevents. This is a genuine forced entry technique on cylindrical locks without inserts, and it is never documented in standard hardware specification content.

Same-Day Shipping

Most specialty and accessory parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for compatibility and identification support.

What Makes Security Parts Different for These Specialty Parts

We document the Falcon M Series spring color change (yellow replaces green) and the four specific lever designs the 030057-002 fits. Without this, a technician cannot confirm the correct part without full disassembly. No other supplier documents this at the product ordering stage.
We document the Von Duprin 283 as wood frame specific and explain the top latch single-point latching failure that occurs when this strike is missing on wood frame SVR installations. Fire-rated SVR assemblies on wood frames require both strikes for code compliance.
We document the pneumatic air supply diagnosis as the first check on 2610 operator failures before ordering a cylinder assembly. A clogged supply line or failing control box valve produces the same symptom as cylinder failure but does not require cylinder replacement.
We document the 36-071 security insert as a pullthrough attack prevention component. The insert is inexpensive but provides genuine forced entry resistance that the ANSI Grade rating of the lock body itself does not address. This fact is absent from all competitor parts content.
We carry all these specialty parts alongside mortise lock parts, exit device parts, door closer parts, and complete Schlage hardware for full building hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

The specialty parts in this guide support every major hardware product line available at SecurityParts.com. They are the completing components that appear alongside locks, closers, and exit devices on every commercial service call.

For Falcon MA Series mortise lock parts including the complete chassis and lever assemblies that the 030057-002 spring serves, browse the Falcon hardware catalog. For Von Duprin complete exit device parts including the 33A/35A/98 series that the 283 top strike serves, browse the Von Duprin catalog. For commercial exit device parts from both Von Duprin and Falcon, browse the exit devices catalog. For LCN complete closer and operator parts including the 2610 Series pneumatic operator that the 2613/2614 cylinders serve, browse the LCN catalog. For commercial door closer parts across all LCN series, browse the door closers catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Falcon M Series, Von Duprin 283, LCN Cylinders and Schlage Trim Accessories

What is the Falcon 030057-002 M Series lever return spring and which locks does it fit?

The 030057-002 is a lever return spring (yellow color, replacing older green springs) for older Falcon M Series mortise lock lever trim. It fits the Avalon, Dane, Quantum, and Sutro lever designs. When this spring fails, the lever droops after operation rather than returning to horizontal, and may not fully retract the latch bolt. It is a limited availability part due to the age of the M Series product line. Contact SecurityParts.com at 845-935-0301 for current availability.

What is the Falcon 005099-000-30 ANSI dust box and when is it required?

The 005099 is a separate ANSI dust box with 1-inch depth for Falcon lock strike applications on hollow metal frames. It is required when a no-box strike plate is installed on a hollow metal frame that has no natural bolt pocket, or when an existing box is damaged and needs replacement separately from the strike plate face. The 1-inch depth accommodates the full ANSI deadbolt throw without the bolt hitting the back of the box before fully extending.

What is the Von Duprin 283 vertical rod top strike and which exit device series does it serve?

The 283 is the vertical rod top strike for wood frame installations with the Von Duprin 33A, 35A, 98, and 9947 SVR exit devices. It mounts in the wood frame header to receive the top latch bolt. Without the 283 on a wood frame installation, the exit device has only single-point latching at the bottom latch. On fire-rated assemblies, this produces a non-compliant installation. The 283 is not for hollow metal frame applications.

What are the LCN 2613-3071 and 2614-3071 cylinder assemblies used for?

These are the size 3 and size 4 standard cylinder assemblies for the LCN 2610 Series pneumatic Auto Equalizer multi-door operator. The 2610 uses compressed air from a single supply to power multiple door operators. Cylinder assemblies require handing specification (LH or RH). Before ordering, confirm air supply pressure at the cylinder supply port, as supply line restrictions and control box valve failures produce the same symptom as cylinder failure but do not require cylinder replacement.

What are Schlage privacy roses 09-459 and 09-486 and when are they replaced?

The 09-459 is the C design privacy rose and 09-486 is the B design privacy rose for Schlage LT Series and related tubular locks. The rose covers the bore preparation area. They are replaced when damaged, scratched, or when finish no longer matches the lever. The design letter (C or B) must match the installed lever design for correct aesthetic pairing. The two designs are not interchangeable.

What are the Schlage 36-031 trim collar, 36-071 trim ring, and 38-031 adapter ring used for?

The 36-031 trim collar covers oversized or damaged bore edges on renovations. The 36-071 trim ring and security insert pack includes a reinforcing insert that prevents the cylindrical lock chassis from being pulled through the door bore in a forced entry attempt. The 38-031 diameter adapter ring corrects bore size mismatches in 2-1/8-inch door prep applications without re-boring. The security insert in the 36-071 addresses a genuine forced entry vulnerability not covered by the lock's ANSI grade rating.

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How to Adjust a Fire Door Closer: NFPA 80 Compliance, Spring Size, and LCN Parts Tuesday, July 14, 2026

Adjusting a fire door closer is not the same as adjusting a standard interior door closer. Standard adjustment focuses on comfort and ADA timing. Fire door adjustment must satisfy NFPA 80 closing speed limits, self-latching requirements, and intumescent seal compression standards that do not apply to non-rated doors. A fire door closer tuned only for gentleness will often fail the NFPA 80 inspection test. This guide covers the full process from spring sizing through valve adjustment, with the specific performance numbers the code requires.

SecurityParts.com stocks LCN fire-rated door closer parts for the full range of LCN closers used on fire door assemblies, including the 4040XP, 4011, 1461, and Sentronic series. Browse LCN fire-rated door closer replacement parts and the complete LCN door closer catalog. Call 845-935-0301 or visit the SecurityParts.com contact page for parts identification support.

What Makes a Fire Door Closer Different from a Standard Closer

A door closer on a fire-rated assembly carries requirements that a standard closer does not. The three most important are the UL 10C listing, the NFPA 80 self-closing and self-latching standard, and the closing speed limits that many facility teams have never seen written as specific numbers.

Every LCN closer carries a UL 10C listing, meaning it has been tested to the Positive Pressure Fire Tests of Door Assemblies standard. The UL label on the closer body is part of the fire door assembly listing. If that label is missing, painted over, or illegible, the door fails inspection even if the closer performs correctly. The label on the closer must match the fire rating of the door and frame assembly.

NFPA 80 also divides fire door operation into three categories: self-closing (equipped with a closing device that closes and latches the door each time it is opened), automatic-closing (equipped with a listed hold-open device that releases on fire alarm activation), and power-operated (equipped with an automatic operator that disconnects on alarm). Most commercial fire doors use surface-mounted door closers and fall into the self-closing category.

Mechanical hold-open arms are an automatic NFPA 80 inspection failure on fire doors. A friction hold-open arm or cush arm in the hold-open position locks the door open mechanically. The fire alarm cannot release it. The door stays open during a fire event. NFPA 80 does not permit this configuration on any fire-rated door. Any hold-open function on a fire door must use a listed electromagnetic device connected to the building fire alarm system, so the door closes automatically when the alarm activates.

NFPA 80 Closing Speed Limits: The Numbers Most Guides Skip

NFPA 80 specifies closing speed limits for fire doors that most adjustment guides never reference. These limits exist because a door closing too fast creates a safety hazard for occupants passing through, and a door closing too slowly may not reliably latch against air pressure differentials and intumescent seal compression during a fire event.

NFPA 80 Closing Speed Limits

Maximum average closing speed24 inches per second

Minimum average closing speed6 inches per second

Measurement zone90 degrees to 12 degrees (not to the frame face)

Test methodStopwatch and digital inclinometer or protractor

ADA minimum closing time (for accessible doors)5 seconds from 90 degrees to 12 degrees

The measurement zone is 90 degrees to 12 degrees of opening, not to the door frame face. A standard interior door measurement that uses "3 inches from the frame" as the endpoint is measuring a different zone than the NFPA 80 sweep zone. When timing a fire door closer for code compliance, the stopwatch runs from the point the door reaches 90 degrees until it reaches the 12-degree position, which is roughly where the latch valve takes over. Record ambient temperature at the time of measurement because hydraulic fluid thickens below 50 degrees Fahrenheit, which slows the closing speed and changes your valve baseline.

NFPA 80 Annex A spring size recommendation: Annex A recommends a size 3 closer for a standard 3-foot interior fire door. An increase to size 4 is recommended for wider doors, doors with intumescent seals or heavy weatherstripping, or doors that must close against corridor air pressure differentials. These are starting-point recommendations, not mandatory minimum specifications. Field verification with a force gauge after adjustment is the final determinant.

Spring Size Selection by Door Width: The Correct Starting Point

Door width is the primary driver of spring size selection, not door weight alone. A spring sized too small will not reliably close and latch the door from full open against intumescent seal compression and air pressure. A spring sized too large creates excessive opening force, which wears the hinges prematurely and may create an ADA compliance problem on accessible route fire doors.

Size 2Doors up to 30 inches wide, interior non-traffic applications. Generally undersized for most fire door assemblies with intumescent seals.
Size 3Standard interior fire doors up to 36 inches wide. NFPA 80 Annex A recommended starting point for 3-foot fire doors. Most common specification for corridor fire doors.
Size 4Interior fire doors 36 to 42 inches wide, or any door with heavy intumescent seals, smoke gaskets, or that operates against corridor air pressure differentials. Also specified when a size 3 cannot reliably latch from full open after valve adjustment is maximized.
Size 5Wide interior fire doors 42 to 48 inches, heavier assemblies, or exterior fire doors with wind exposure. Verify ADA opening force after setting spring power.
Size 6Heavy doors, large assemblies, or exterior fire doors in high-wind locations. Opening force must be verified with a gauge. Low-energy automatic operator may be the more appropriate specification when size 6 closing force creates accessibility problems.

An over-powered spring causes two problems, not one. An oversized spring pushes the opening force above the ADA 5-pound limit on accessible route doors. It also accelerates hinge wear. Every time the door closes, the full spring force transfers through the hinge knuckles. A spring running at size 5 or 6 on a door that only needs size 3 creates progressive hinge damage that eventually leads to door sag, misalignment, and latching failure. The correct spring size is the smallest size that reliably closes and latches the door from full open. Confirm with a force gauge after setting power.

Spring Power vs Valve Adjustment: Which Controls What

What the Valves Control

The sweep valve (S), latch valve (L), and backcheck valve (BC) control the speed at which the door moves through different phases of the closing cycle. They regulate how fast the spring force translates into door movement by restricting or releasing hydraulic fluid flow. They do not control closing force. A closer with inadequate spring power cannot be fixed by opening the valves. All that does is allow the spring to move the door faster toward a latch it still cannot engage reliably.

What the Spring Controls

The spring determines how much closing force the closer delivers. On the LCN 4040XP, spring power is adjusted externally using the green power adjustment dial on the spring tube, without opening the body or replacing parts. Turn the dial clockwise to increase power in one-position increments. On fixed-power closer models, spring power cannot be adjusted in the field. If the door does not reliably latch and the spring size is too small, the closer must be replaced with a correctly sized unit.

Why Intumescent Seals Change the Latch Speed Calculation

This is the detail that makes fire door latch valve adjustment different from standard door adjustment. Fire doors equipped with intumescent seals have an additional resistance load at the end of the closing arc. The intumescent seal material compresses against the frame as the door enters the final degrees before latching. This compression requires more force and speed through the latch zone than a standard door without seals.

The latch valve on a fire door must be set fast enough not just to engage the strike, but to drive the door through the intumescent seal compression and seat it fully against the frame. A latch valve setting that works perfectly on a non-sealed door will often produce the bounce-back failure on a fire door with intumescent seals. The door appears to close, contacts the frame, and bounces back one to two inches without fully latching. Browse LCN door closer replacement parts including spring assemblies and complete bodies at SecurityParts.com.

The adjustment order that prevents chasing your tail. Always follow this sequence: spring power first, then sweep valve, then latch valve, then backcheck. If you adjust the sweep valve before confirming adequate spring power, you may open the sweep all the way to generate closing momentum and end up with a door that slams rather than closes smoothly. Spring power is the foundation. Every valve setting after that assumes the spring is correct for the door.

Before You Touch Any Valve: Three Pre-Checks

Check Hinge Binding First

Hinge binding is the most common non-closer cause of fire door closing failures, and it mimics a closer that is set too slow or too weak. If a hinge is binding, the door will stall at the same point in the closing arc every time, regardless of how the closer is adjusted. Before adjusting any valve, open the door slowly by hand through its full arc and feel for resistance points. Any point where the door requires noticeably more effort to push through indicates a binding condition at that arc position. Re-torque all hinge fasteners, check for hinge misalignment, and confirm the door is hanging square in the frame before proceeding to closer adjustment.

Check the Closer Label

The UL 10C label must be present, legible, and unobscured before any adjustment. A closer that passes every functional test but has a missing or painted-over label fails the NFPA 80 inspection regardless of how well it performs. If the label is damaged, a field relabeling service can restore the listing on a sound unit. No label means no compliant fire door assembly, and adjustment does not fix that.

Confirm No Mechanical Hold-Open Arm Is Present

If a cush arm or friction hold-open arm is installed, remove it before any adjustment. A fire door closer adjusted with a hold-open arm in place produces compliant results during the adjustment session that immediately become non-compliant the moment someone engages the hold-open. The hold-open must be removed entirely before the adjustment baseline is established.

Tools Required

3/32-inch hex key for sweep, latch, and backcheck valve adjustment on most LCN closers
5/32-inch hex key for spring power adjustment dial on LCN 4040XP
Stopwatch for timing the sweep arc from 90 degrees to 12 degrees
Digital inclinometer or door angle gauge for accurately identifying the 90-degree and 12-degree measurement points
Door force gauge for measuring opening force on accessible route fire doors where ADA compliance must be verified alongside NFPA 80 compliance
Small flathead screwdriver as backup for older LCN models where valves take a flathead rather than hex

Step-by-Step Fire Door Closer Adjustment

Confirm UL 10C label is present and legible Locate the label on the closer body. It must be clearly visible, unobscured, and not painted over. If missing or illegible, stop and address the label issue before proceeding. Adjustment of an unlabeled closer does not restore the assembly's fire rating.
Remove any mechanical hold-open arm A cush arm, friction holder, or any mechanical hold-open device must be removed from the door before adjustment begins. Fire doors cannot use mechanical hold-open configurations under NFPA 80.
Check for hinge binding Open the door manually through its full arc. Identify any resistance points. Re-torque hinge fasteners, correct any misalignment, and confirm the door swings freely before touching the closer. Hinge binding produces the same symptoms as a under-powered closer and wastes adjustment time if not addressed first.
Test spring power from full open with existing valve settings Open the door fully and release it. Watch the full closing cycle without touching the door. If the door closes and latches cleanly, spring power is adequate. If it stalls, slows dramatically, or fails to latch, increase the spring power before adjusting any valves.
Adjust spring power if needed (LCN 4040XP) Locate the green power adjustment dial on the spring tube. Turn clockwise one position to increase spring power. Re-test from full open. Repeat until the door closes and latches reliably from full open at moderate valve settings. Do not over-power. Verify opening force with a door force gauge on any door on an accessible egress route.
Set all valves to baseline Turn all valves gently clockwise to the closed position. Do not overtighten. Open each valve 1.5 turns counterclockwise. This is the approximate factory starting position for LCN closers.
Set the sweep valve (S) within NFPA 80 speed limits Open the door to 90 degrees. Release and time the sweep arc from 90 degrees to 12 degrees. The result must be between 6 and 24 inches per second on average. For a 36-inch door, 6 inches per second over that arc produces approximately a 5-second sweep, which also satisfies the ADA 5-second minimum on accessible route doors. If the sweep is outside the NFPA 80 limits, adjust the S valve in 1/8-turn increments and re-test. Record ambient temperature alongside the measurement.
Set the latch valve (L) for intumescent seal compression Watch the door through the final 12 degrees before the frame. The door must carry sufficient speed through this zone to compress the intumescent seals and fully engage the strike. If the door produces a "bounce-back" where it contacts the frame and rebounds one to two inches without latching, the latch valve is set too slow. Open the L valve counterclockwise in 1/8-turn increments until the bounce-back stops and the door seats cleanly on every cycle. A clean latch produces a distinct single-click engagement, not a thud or a bounce.
Set the backcheck valve (BC) Open the door aggressively to simulate a hard push or a wind gust. The backcheck should engage at approximately 70 to 75 degrees to cushion the opening and prevent the door from slamming against the stop. If backcheck engages too early and restricts normal opening, open the BC valve slightly counterclockwise. If there is no resistance at full open, close the BC valve clockwise until resistance is felt in the 70 to 75 degree range.
Run three consecutive full-open release tests Open the door fully to its stop position and release. All three releases must produce complete latching without manual assistance. This is the NFPA 80 field verification test. A single failure in three cycles means the adjustment is not complete. Investigate strike alignment, intumescent seal resistance, and latch valve setting before re-testing.
Document settings, ambient temperature, and date Record the valve positions, spring power setting, measured sweep time, opening force measurement (if applicable), and ambient temperature. This record links directly to the annual NFPA 80 inspection requirement and provides the baseline for restoring calibration after seasonal temperature drift.

Fire Doors That Need to Be Held Open: The Compliant Configuration

Many fire doors serve high-traffic corridors where holding the door open during business hours is operationally necessary. The mechanical hold-open arm is not a compliant solution on a fire door. The correct configuration is a listed electromagnetic hold-open device connected to the building fire alarm system.

LCN Sentronic closers integrate the electromagnetic hold-open function directly into the closer body. When power is normal and no fire alarm is active, the Sentronic magnet holds the door open at the desired position. When the fire alarm activates, the panel interrupts power to the Sentronic, the electromagnetic hold releases, and the mechanical closer spring closes and latches the door automatically.

The LCN SEM 7800 Series electromagnetic holders are a wall-mounted or floor-mounted alternative that pairs with any standard mechanical LCN closer. They are specified when an existing non-Sentronic closer is in place and the facility wants to add compliant hold-open function without replacing the closer body. Both configurations automatically release on fire alarm and allow the closer to perform its self-closing function.

When a delayed action setting is used in conjunction with a Sentronic or SEM configuration, the maximum permissible delay on a fire door is 25 seconds from release to full close and latch. Delayed action beyond 25 seconds on a fire door does not provide enough confidence that the door will achieve positive latching before a fire event progresses through the corridor. Browse LCN Sentronic and SEM 7800 Series hold-open parts at SecurityParts.com.

Fire door closers are not required to meet the ADA 5-pound opening force limit. NFPA 80 specifically excludes fire doors from the accessibility standard opening force requirements. A fire door that must close against corridor air pressure and compress intumescent seals may require spring power that exceeds the 5-pound opening force. On accessible route fire doors where both requirements apply, the correct solution is a low-energy automatic door operator rather than a weaker spring. LCN low-energy operators are UL 10C listed and disconnect from power on fire alarm activation, allowing the closer to close the door mechanically during a fire event.

Annual NFPA 80 Closer Inspection Checklist

NFPA 80 requires annual inspection of every fire door assembly, and the door closer is one of the specific components inspected. During each annual inspection, the closer must pass a visual check and a functional test. Use this checklist as part of the annual inspection record for each fire door in the facility.

Closer body is securely mounted to the door with no loose fasteners at the mounting plate or cover
Arm is securely mounted at both the closer spindle and the shoe bracket with no loose fasteners or play at either connection point
Closer body shows no cracks in the casting, no deformation of the body, and no physical damage
No hydraulic fluid visible on the closer body, the door, the frame, or the floor below the closer
Cover plate is intact with no cracks and all cover screws present (missing cover screws on exterior fire doors allow debris into the valve area)
UL 10C label is present on the closer body, legible, unobscured, and not painted over
No mechanical hold-open arm or friction hold-open device is attached to the arm or the door
If electromagnetic hold-open is installed, the hold-open releases when simulated fire alarm signal is applied and the door closes and latches within 25 seconds
Door closes completely and positively latches when released from the full open position without manual assistance
Closing speed falls between 6 and 24 inches per second averaged over the 90-degree to 12-degree sweep zone
No field modifications visible on the closer body, arm, or mounting: no drilled holes, no welded attachments, no bent arm sections
Inspection result, closer model, valve settings, spring power position, and inspector name documented and retained

When Adjustment Cannot Fix the Problem

Hydraulic Fluid Leak

A closer with oil on the body, arm, or floor cannot hold valve settings because the hydraulic pressure the valves regulate is draining out. Adjustment provides temporary results at best. A leaking closer on a fire door is a direct NFPA 80 deficiency. The unit must be replaced. Browse LCN door closer parts diagrams to identify the correct replacement body for your model.

Worn or Broken Spring

A closer past its rated cycle life loses spring tension. On LCN 4040XP models, the green power dial reaches its maximum position and the door still does not close reliably from full open. The spring assembly or the complete closer body must be replaced. Field spring replacement in a sealed hydraulic closer is not recommended without factory tooling.

Bounce-Back That Does Not Resolve with Latch Valve Adjustment

If the bounce-back failure persists after fully opening the latch valve, the problem is not the valve setting. Investigate in this order: strike alignment (latch bolt centerline must align with the strike pocket centerline), intumescent seal condition (a damaged or compressed-beyond-recovery seal creates permanent resistance the closer cannot overcome), and spring size (the spring may be undersized for the door assembly with its seals). A bounce-back that cannot be resolved with latch valve and spring adjustments points to a strike or seal issue, not a closer issue.

Bent or Damaged Arm

A bent closer arm changes the geometry of the closer-to-door connection, producing inconsistent closing speed through different arc positions. Visual inspection at full open and at closed position confirms whether the arm is straight and whether all pivot points are intact. A cracked casting at any pivot requires arm replacement before any adjustment is meaningful. The arm is a model-specific component available as a separate replacement part.

Why Choose SecurityParts.com for LCN Fire Door Closer Parts

SecurityParts.com stocks LCN door closer components for the complete range of LCN fire-rated closers with over 30 years in commercial door hardware. We stock the 4040XP, 4011, 1461, Sentronic, and SEM 7800 Series parts needed for fire door assembly compliance. All LCN closers carry UL 10C listings for fire-rated assemblies.

Browse LCN fire door closer replacement parts, LCN door closer parts diagrams by model, and the complete LCN door closer catalog. For general door closer adjustment on non-fire doors, see the commercial door closer adjustment guide. For closer type selection across all applications, see the commercial door closers types guide. Browse the full SecurityParts.com parts catalog or call 845-935-0301 for same-day shipping support.

Frequently Asked Questions About Fire Door Closer Adjustment

What is the NFPA 80 closing speed requirement for a fire door closer?

NFPA 80 specifies that the average closing speed must not exceed 24 inches per second and must be at least 6 inches per second. This is measured from 90 degrees to 12 degrees of opening, not to the door frame face. A door closing faster than 24 inches per second creates a safety hazard for occupants. A door closing slower than 6 inches per second may not reliably latch against air pressure and intumescent seal resistance.

What spring size does NFPA 80 recommend for a fire door closer?

NFPA 80 Annex A recommends a size 3 closer for a standard 3-foot interior fire door. An increase to size 4 is recommended for wider doors, doors with heavy intumescent seals, or doors that must close against corridor air pressure differentials. Door width is the primary driver of spring size selection. Always verify opening force with a door force gauge after setting spring power, especially on doors located on accessible egress routes.

Can a mechanical hold-open arm be used on a fire door?

No. Mechanical hold-open arms and friction hold-open devices are prohibited on fire-rated doors under NFPA 80. A mechanical hold-open cannot be released by the fire alarm system. The correct configuration for a fire door that needs to stay open during business hours is a listed electromagnetic hold-open device connected to the building fire alarm system. LCN Sentronic closers and SEM 7800 Series electromagnetic holders are both compliant solutions that release automatically when the fire alarm activates.

Why does my fire door closer latch on standard doors but bounce back on fire doors?

Fire doors equipped with intumescent seals create additional resistance in the final degrees of the closing arc. The intumescent seal material compresses against the frame as the door approaches the closed position. This compression requires more speed and force through the latch zone than a non-sealed standard door. If the latch valve is set at the same position used for a standard door, the door will contact the frame and bounce back without fully latching. Open the latch valve counterclockwise in small increments until the door carries through the intumescent seal resistance and seats cleanly on every cycle.

What is the correct order to adjust a fire door closer?

Always follow this sequence: spring power first, then sweep valve, then latch valve, then backcheck. Adjusting valves before confirming adequate spring power produces misleading results because you may fully open the sweep valve to generate momentum for a door that simply lacks enough spring force to latch reliably. Spring power is the foundation. Valve settings only make sense once the spring is confirmed correct for the door width and seal resistance.

When should a fire door closer be replaced instead of adjusted?

Three conditions require replacement rather than adjustment. First, if hydraulic fluid is visible on the closer body, door, or floor, the seals have failed and the unit cannot hold valve settings. Second, if the spring power dial on an LCN 4040XP is at its maximum position and the door still does not close reliably from full open, the spring is worn beyond adjustment range. Third, if the closer body casting is cracked or physically damaged. A bent arm is a separate replacement component and does not require replacing the full closer body. Browse LCN door closer replacement parts at SecurityParts.com for model-specific components.

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Schlage and Falcon Strike Plates, Deadlatches and Latch Bolt Combinations: Complete Parts Guide Monday, July 13, 2026

Security Parts carries the complete range of Schlage and Falcon strike plates, deadlatches, and latch bolt combinations. Strike plates in the 10-series include the 10-094 flat square-corner strike (B Series standard), the 10-087 ANSI strike with dust box (B600/700 Grade 1 applications), the 10-092 full lip round corner (Falcon B700 standard), the 10-095 full lip square corner, and the Falcon 10-064 circular thimble drive-in. Deadlatches include the 16-228 (square corner, L Series and cylindrical) and 16-260 (dual option). Latch bolt combinations include the 12-339 dual option combination (CS210 and B Series), the 16-483 fixed square corner combination, and the 16-484 large combination with 5-inch backset option. The 12-340 is the adjustable bolt for L Series and CS210 applications.

Strike plates and latch bolts are the most frequently ordered individual parts on any commercial door hardware service call. They are also the most frequently mis-ordered. A strike that is the wrong corner style leaves visible gaps in the frame. A latch bolt with the wrong backset will not engage the strike. A deadlatch specified where a spring latch was installed fails to provide the deadlocking protection the facility expects. Getting these parts right requires knowing which lock series they serve, what the existing frame mortise requires, and whether a box, thimble, or standard flat plate is appropriate for the door frame material.

Browse the complete Schlage and Falcon parts catalog at SecurityParts.com. For the lock series these components serve, browse Schlage B Series deadbolt parts, Schlage L Series mortise lock parts, cylindrical lock parts, and Falcon hardware parts.

1-1/8" x 2-3/4" 10-094 standard deadbolt strike dimensions for B Series applications

1-1/4" x 4-7/8" 10-087 ANSI strike dimensions for Grade 1 B600/700 applications

Dual option 16-260 and 12-339 include both square and round corner faceplates in one package

J-templates Every Schlage strike has a corresponding J-series jamb template for correct positioning

Strike Plates: The Most Misunderstood Door Hardware Component

A strike plate is the metal fitting mounted in the door frame that receives the lock's latch bolt or deadbolt when the door closes. It sounds simple, and it is mechanically. But the number of variables in strike plate selection produces more wrong orders and more callbacks than almost any other single door hardware part. Understanding these variables before ordering eliminates most strike plate service calls.

The four variables that determine the correct strike plate are: the lock series (which determines the bolt dimensions), the corner style of the existing frame mortise (square corner or round corner), the frame material (hollow metal requiring a dust box or wood accepting either), and whether a full lip, flat, or thimble profile is needed for the specific application.

Square Corner vs Round Corner: The First Decision

The corner style describes the shape of the strike plate faceplate corners where the plate sits flush in the door frame. This is not a preference or aesthetic choice. It is determined by the shape of the existing mortise pocket in the door frame, which was cut at the time of original installation and cannot be changed without additional frame work.

Square corner (90-degree straight corners) is standard for hollow metal door frames in commercial construction and for most modern wood frame installations that used a chiseled or milled square mortise. The vast majority of commercial and institutional door installations use square corner strikes.

Round corner (typically 1/4-inch radius) is found on older wood frame installations where the mortise pocket was routed with a router bit that leaves curved corners, and on installations that specifically called for round corner strikes in the original specification. Round corner strikes are less common in commercial construction but remain in widespread use in renovation and repair work on older buildings.

The corner mismatch that produces the most strike plate re-orders: Ordering a square corner strike for a round corner mortise pocket requires the installer to chisel the pocket corners to accept the new strike. If this is not done, the strike plate face sits above the frame surface at the corners, creating a visible gap and a strike that rattles. Ordering a round corner strike for a square corner pocket leaves the strike plate recessed at the corners with visible frame material visible beside the plate. Before ordering any strike plate on a repair or replacement job, look at the existing mortise pocket corners. The shape of the existing pocket determines which corner style to order, not the corner style of the existing strike.

Dust Box vs No-Box Strikes: Frame Material Determines the Choice

A dust box is the metal enclosure that mounts behind the strike plate face and extends into the door frame, creating a protected cavity that receives the latch or deadbolt. The name comes from the box's original purpose of protecting the bolt pocket from paint, debris, and moisture that would otherwise accumulate in an open frame mortise pocket.

For hollow metal door frames in commercial applications, a dust box is required on every strike plate. The metal frame provides no natural wood pocket for the bolt: without a box, the bolt would enter an empty void in the metal frame with nothing to contain or guide it. The dust box creates the pocket the bolt needs to engage reliably on every door closure.

For solid wood door frames, a dust box is not strictly required because the wood provides its own pocket around the mortise. However, box strikes are preferred on wood frames for two reasons: the box prevents wood shrinkage from closing the pocket over time (especially in climates with significant seasonal humidity variation), and the box prevents moisture and paint from accumulating in the pocket on painted frames. The no-box strike is acceptable on interior wood frame applications with low moisture exposure.

The paint-filled strike pocket that generates the most residential latch complaints: Interior wood door frames in apartment buildings and older commercial construction that have been painted multiple times over the years frequently develop strike pockets so filled with paint that the latch bolt cannot fully extend into the pocket. The door appears to latch but does not engage the strike bolt pocket correctly, causing the door to pop open from vibration or air pressure. The fix is cleaning the paint from the pocket, not adjusting the latch. If a box strike is installed during the next strike replacement, the enclosed pocket prevents future paint accumulation without requiring cleaning.

Full Lip vs Flat Strikes: When the Frame Dimension Matters

A full lip strike has an extended plate section (the "lip") that projects beyond the strike face onto the door stop surface of the frame. The lip covers the gap between the door face and the frame face, providing additional protection against latch shimming attacks (using a card or thin tool to push the latch back through the gap between door and frame).

A flat strike (no-lip or short-lip) sits flush in the frame face mortise without the extended projection. Flat strikes are used where the door stop geometry does not permit a full lip or where the specification does not require the additional shimming protection.

For commercial security applications, full lip strikes provide better resistance to shimming attacks and are preferred on exterior and secured interior doors. Flat or short-lip strikes are appropriate for interior doors where latch shimming is not a security concern.

Schlage Strike Plate Products at Security Parts

Schlage 10-094

Flat Square Corner | No Box | 1-1/8" x 2-3/4"

Standard flat square corner deadbolt strike for B Series B500 and B600 applications and Falcon cylindrical applications. 1-1/8 inch by 2-3/4 inch. No dust box. Used on wood frames and in repair applications where the original pocket accommodates a no-box strike. Template J884 (wood jamb). Current production does not include a box; prior versions did. Confirm frame material before ordering.

Schlage 10-087

ANSI | Square Corner | With Dust Box | 1-1/4" x 4-7/8"

ANSI-specification strike plate with dust box for B600 and B700 Grade 1 deadbolts and high-security applications. 1-1/4 inch by 4-7/8 inch provides larger frame coverage and a deeper bolt pocket than the standard 10-094. The larger ANSI footprint increases kick-in resistance by spreading the bolt load across more frame material. Template J918 (wood jamb), J919 (metal jamb). Standard for Grade 1 commercial entries.

Schlage 10-116

Round Corner | No Lip | No Box | 1-1/8" x 2-3/4"

Round corner deadbolt strike, 1-1/8 inch by 2-3/4 inch, no lip, no box. Used when the frame mortise has 1/4-inch radius corners. Most commonly found on older residential and light commercial wood frame installations. Also specified as the round-corner option for CS210 deadbolt strike when the frame mortise was originally cut with a round-corner template.

Falcon Strike Plates at Security Parts

Falcon 10-064

Circular Drive-In Thimble | B600/B700 Series

Circular (thimble) drive-in strike for Falcon and Schlage B600/700 Series deadbolts on narrow frame or aluminum frame applications. Installed by driving into a pre-bored hole in the frame edge rather than mortising a flat pocket in the frame face. The thimble format is the correct choice for aluminum storefront frames where the frame stile is too narrow for a standard flat strike plate. Template J563. Also used where a flush, hidden strike is preferred for aesthetic reasons.

Falcon 10-087

ANSI Square Corner | With Plastic Dust Box | 4-7/8" x 1-1/4"

ANSI strike with plastic dust box for Falcon B600/700 and Schlage applications. 4-7/8 inch by 1-1/4 inch, 1-3/16 inch lip to center. Plastic box version as noted in part number 10-087. Identical footprint to the Schlage 10-087 ANSI specification. Used on Grade 1 applications requiring ANSI strike dimensions with box protection. Template J918 wood jamb, J919 metal jamb.

Falcon 10-092

Full Lip Round Corner | No Box | 2-1/4" x 1-5/8"

Full lip round corner strike, 2-1/4 inch by 1-5/8 inch, 1-1/8 inch lip, 1/4-inch radius corners. No box. Used on Falcon cylindrical locks and Schlage cylindrical applications where a full lip provides shimming protection and the frame has round-corner mortise pockets. Template J786. The full lip covers the gap between door and frame, eliminating the shimming attack vector on spring latch cylindrical locks.

Falcon 10-095

Full Lip Square Corner | No Box | 2-1/4" x 1-5/8"

Full lip square corner strike, 2-1/4 inch by 1-5/8 inch, 1-1/8 inch lip. No box. Same dimensions as the 10-092 but with square corners. Used on square-corner frame mortises that require full lip coverage. Template J787. The square corner version covers the majority of commercial cylindrical lock applications where full lip shimming protection is required on hollow metal frames.

Strike Selection by Lock Series: Quick Reference

Lock Series	Standard Strike	Wood Jamb Template	Metal Jamb Template	Notes
B500 (Grade 2 deadbolt)	10-094 flat sq corner	J884	J477	No box. Add 10-087 for ANSI upgrade
B600 (Grade 1 deadbolt)	10-087 ANSI w/box	J918	J919	ANSI footprint standard on Grade 1
B600 (thimble option)	Falcon 10-064 thimble	J563	J563	For narrow/aluminum frames only
Falcon cylindrical (round corner frame)	Falcon 10-092 full lip	J786	N/A	Full lip, round corner, no box
Falcon cylindrical (sq corner frame)	Falcon 10-095 full lip	J787	N/A	Full lip, square corner, no box
CS210 (deadbolt strike)	10-116 round corner or 10-094	Varies	Varies	Two-strike set required; see CS210 catalog

Schlage Deadlatches: 16-228 and 16-260

A deadlatch is a spring-operated latch bolt that incorporates an automatic deadlocking mechanism. Standard spring latches can be manipulated back into the door with a thin card or tool inserted between the door edge and the frame. A deadlatch prevents this: a small plunger (the deadlocking plunger) extends alongside the main latch bolt when the door closes. When this plunger contacts the strike plate face, it locks the latch bolt in the extended position, preventing the bolt from being pushed back without operating the lever from inside or the key from outside.

Schlage 16-228: Standard Deadlatch

The Schlage 16-228 is a square corner deadlatch with a 1-1/8 inch by 2-1/4 inch faceplate. It is the standard deadlatch replacement for Schlage L Series mortise locks and cylindrical lock applications where square corner frame prep exists. The 16-228 is a fixed square-corner configuration, suitable for hollow metal frame installations and wood frame installations with square-corner mortise pockets.

Schlage 16-260: Dual Option Deadlatch

The Schlage 16-260 is the dual option deadlatch: it includes both square and round corner faceplates in the same package, along with a 1-inch by 2-1/4-inch faceplate dimension. The dual option design means one part number covers more installation scenarios, reducing the need to correctly identify corner style before ordering. On a renovation project where the existing frame corner style is uncertain or inconsistent across multiple doors, the 16-260 eliminates the risk of ordering the wrong corner style.

The deadlocking plunger fact that generates most "door pops open" complaints: A deadlatch only deadlocks correctly when the deadlocking plunger contacts the strike plate face as the door closes. If the strike plate is positioned too far from the door edge (a misaligned strike), the latch bolt enters the strike pocket but the deadlocking plunger hangs in open air rather than contacting the strike face. The door appears latched but is not deadlocked: the latch can be pushed back from outside. This is the most common cause of interior office doors that appear latched but pop open when pushed firmly. The fix is adjusting the strike position so the deadlocking plunger contacts the strike face, not replacing the latch bolt.

Schlage Latch Bolt Combinations: 12-339, 16-483, 16-484

Latch bolt combinations package both a deadbolt and a deadlatch in a single assembly for applications where both are required and pre-matched components are preferred over sourcing separately.

Schlage 12-339: Dual Option Deadbolt/Deadlatch Combination

The Schlage 12-339 is a 1-inch by 2-1/4-inch dual option combination containing both a deadbolt and a deadlatch. Dual option means both square and round corner faceplates are included. The 12-339 fits standard 2-3/8-inch or 2-3/4-inch backsets. It is used in the Schlage CS210 interconnected lock as the complete latch assembly replacement and in B Series and related applications where a matched combination ensures the deadbolt and latch have identical faceplate dimensions and compatible backsets.

The 12-340 is the adjustable bolt variant: a 1-inch by 2-1/4-inch square corner deadbolt only (not a combination) that adjusts for both 2-3/8-inch and 2-3/4-inch backsets. It is used in Schlage L Series mortise locks and CS210 applications where only the deadbolt requires replacement rather than the full combination.

Schlage 16-483: Fixed Square Corner Combination

The Schlage 16-483 is a square corner deadbolt/deadlatch combination with 1-1/8 inch by 2-1/4 inch faceplates. Where the 12-339 is dual option (both corner styles included), the 16-483 provides fixed square corner configuration. It is used when the frame prep is confirmed as square corner and the larger 1-1/8-inch faceplate width is preferred over the 1-inch width of the 12-339.

Schlage 16-484: Large Combination with 5-Inch Backset Option

The Schlage 16-484 is a square corner deadbolt/deadlatch combination with 1-inch by 2-1/4 inch faceplates and an optional 5-inch backset configuration. The 5-inch backset option is used on doors where the bore preparation is set further back from the door edge than the standard 2-3/8-inch or 2-3/4-inch backsets. This is most common on glass door applications where the bore must clear the glass panel edge, and on wide-stile commercial doors where hardware aesthetics require a further setback from the door edge.

Schlage 16-132: 5-Inch Backset Deadlatch

The Schlage 16-132 is a square corner deadlatch with a 1-1/8 inch by 2-1/4 inch faceplate specifically for the 5-inch backset configuration. It is used on the same applications as the 16-484's 5-inch backset option but when only the deadlatch (not the combination) requires replacement. The 16-228 and 16-260 cover standard 2-3/8-inch and 2-3/4-inch backsets; the 16-132 specifically addresses the 5-inch backset requirement.

What is a Deadlatch vs a Deadbolt vs a Spring Latch?

These three terms are frequently confused and the confusion generates mis-ordered parts. Understanding the distinction prevents returning the wrong part.

Bolt Type	How It Works	Auto-Locks?	Requires Key to Open?	Example Parts
Spring latch	Spring-loaded bolt that retracts when lever is turned; can be shimmed back	No	No (lever only)	THP-8201, standard cylindrical latch
Deadlatch	Spring-loaded bolt with deadlocking plunger; cannot be shimmed when plunger contacts strike	Yes (auto)	No (lever only from inside)	16-228, 16-260, THP-8219
Deadbolt	Manually thrown bolt with full 1-inch throw; not spring loaded	No (manual)	Yes (key or thumbturn)	B500, B600, 12-340 bolt
Combination	Both deadbolt and deadlatch in matched set	Partial (deadlatch auto)	Partially (deadbolt requires key)	12-339, 16-483, 16-484

The spring latch replacement that eliminated deadlocking protection without anyone noticing: A common scenario in commercial buildings: a deadlatch (16-228 or 16-260) on an office or suite entry door is replaced during a service call with a standard spring latch because the service technician only matched the bolt dimensions and backset without noting the deadlocking plunger. The door latches and the lever functions correctly. But the deadlocking protection is gone: the latch can now be shimmed back from outside. This happens on probably 10 to 15 percent of cylindrical lock latch replacements in buildings where the original specification included deadlatches but the replacement was sourced by bolt dimensions alone. Always confirm the deadlatch function when replacing any latch on a secured door, not just the dimensions.

How to Identify the Correct Strike or Latch Before Ordering

Three measurements and two observations determine the correct part for any strike or latch replacement.

1. Bolt or latch body dimensions (width x length of faceplate). Remove the existing strike or latch and measure the faceplate. The most common commercial dimensions are 1-1/8 inch by 2-1/4 inch (latch bolts and combination faceplates) and 1-1/8 inch by 2-3/4 inch (deadbolt strikes).

2. Backset (for latches). Measure from the door edge to the center of the bolt bore, with the bolt removed. Standard backsets are 2-3/8 inch and 2-3/4 inch. The 5-inch backset is a specialty configuration.

3. Corner style (for strikes). Observe the existing frame mortise pocket corners. Square equals 90-degree straight corners. Round equals 1/4-inch radius curved corners.

4. Frame material (for strikes). Hollow metal frame requires a dust box strike. Wood frame accepts either box or no-box.

5. Bolt type (for latches). Does the existing latch have a small secondary plunger alongside the main bolt? If yes, it is a deadlatch and requires a deadlatch replacement. If the bolt is a single simple spring bolt, it is a standard spring latch.

Browse the complete strike plates and latch bolts catalog at SecurityParts.com. For the full range of Schlage lock parts, browse the B Series deadbolt parts, L Series mortise lock parts, ND Series cylindrical lock parts, and CS210 interconnected lock parts. For Falcon lock hardware parts, browse the Falcon hardware catalog. Pre-order support at 845-935-0301 or the contact page.

Why Choose Security Parts for Strike Plates and Latch Bolt Parts

Frame material guidance, deadlatch replacement warning, paint-filled pocket diagnosis, corner mismatch prevention, and same-day shipping on stocked parts.

Deadlatch Replacement Warning

We document that replacing a deadlatch with a spring latch eliminates deadlocking protection without any visible change in door operation. This is the most common undetected security downgrade in commercial buildings.

Corner Mismatch Prevention

We document that the existing mortise pocket shape determines the corner style, not the existing strike. Ordering by the existing strike's corner style when the pocket has been re-cut produces a gap-fitting replacement.

Deadlocking Plunger Fact

We document the deadlocking plunger contact requirement: a deadlatch only deadlocks when the plunger contacts the strike face. A misaligned strike that allows the latch to enter the pocket without plunger contact leaves the door unlocked.

Same-Day Shipping

Most strike plates and latch bolts ship same day from US warehouses. Call 845-935-0301 or use the contact page for corner style and bolt type confirmation support.

What Makes SecurityParts.com Different for Strike Plates and Latch Bolts

We document the spring latch to deadlatch downgrade: replacing a 16-228 or 16-260 deadlatch with a standard spring latch removes deadlocking protection invisibly. This security vulnerability is never documented at the parts ordering stage by any competitor.
We document the deadlocking plunger contact requirement. A perfectly functioning deadlatch that does not contact the strike face does not deadlock. Strike alignment is a prerequisite for deadlatch function that is never explained in competitor parts content.
We document that the 10-094 current production no longer includes a box, while prior versions did. Ordering the 10-094 for a hollow metal frame application where the previous version included a box will produce a no-box replacement that requires additional frame work.
We document that the ANSI strike (10-087) is not just a larger version of the 10-094: it addresses a different security level (Grade 1 B600/700 vs Grade 2 B500) with a larger force-distribution footprint for improved kick-in resistance.
We carry strike plates and latch bolts alongside B Series deadbolt parts, L Series mortise lock parts, cylindrical lock parts, LCN door closer parts, and exit device parts for complete door hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

Strike plates and deadlatches are components of every complete commercial door hardware assembly. They appear on every door alongside the lock body, closer, and exit device.

For Schlage B Series B500 and B600 deadbolt parts including the deadbolts these strikes serve, browse the deadbolts catalog. For Schlage L Series mortise lock parts including the mortise case, lever, and cylinder components that pair with these latch bolts, browse the mortise locks catalog. For Schlage ND and ALX Series cylindrical lock parts including the chassis and lever that these strikes serve, browse the cylindrical locks catalog. For Schlage CS210 interconnected lock parts including the complete strike combination set, browse the interconnected locks catalog. For Schlage CL Series cabinet lock parts including bar strikes and slotted strikes for cabinet applications, browse the cabinet locks catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Schlage and Falcon Strike Plates and Deadlatches

What is the difference between a square corner and round corner strike plate?

Square corner means the faceplate has 90-degree straight corners. Round corner means the corners have a 1/4-inch radius curve. The frame mortise pocket shape determines which is needed: the strike must match the pocket. Square corner is standard for commercial hollow metal frames. Round corner is found on older wood frame installations with routed mortise pockets. Using the wrong corner style leaves visible gaps between the strike face and the frame.

What is the difference between a strike plate with a dust box and one without?

A dust box creates a protected metal pocket behind the strike face that receives the bolt. It is required for hollow metal frames that have no natural wood pocket for the bolt. No-box strikes rely on the frame material's own mortise pocket and are used on wood frames. On commercial hollow metal frame applications, always specify a box strike. The 10-087 ANSI strike with box is the correct Grade 1 commercial standard; the 10-094 (no box) is used for Grade 2 wood frame applications.

What is a Schlage 16-228 deadlatch and when is it used?

The 16-228 is a square corner deadlatch with a 1-1/8 inch by 2-1/4 inch faceplate for Schlage L Series mortise locks and cylindrical lock applications. A deadlatch adds a secondary plunger that prevents the bolt from being shimmed back when the plunger contacts the strike face. It provides security beyond a spring latch without requiring a deadbolt. The 16-260 is the dual option version with both square and round corner faceplates included.

What is the Schlage 12-339 deadbolt/deadlatch combination and what lock series does it fit?

The 12-339 is a dual option combination assembly containing both a deadbolt and a deadlatch. It fits 2-3/8-inch and 2-3/4-inch backsets and is used in the CS210 interconnected lock and B Series applications where a pre-matched combination simplifies replacement. The 16-483 is the fixed square corner version; the 16-484 includes a 5-inch backset option. The 12-340 is the adjustable deadbolt only (no latch) for L Series and CS210 deadbolt-only replacement.

What is the Falcon 10-064 circular drive-in thimble strike?

The 10-064 is a circular thimble strike driven into a pre-bored hole in the door frame edge rather than mortised in the frame face. It is used for narrow aluminum and steel frames where standard flat strike plates do not fit, and for applications where a hidden strike appearance is preferred. Template J563. Specified on aluminum storefront frame applications where the frame stile is too narrow for the 10-094 or 10-087.

What is an ANSI strike and when is the Schlage 10-087 used instead of the 10-094?

The 10-087 is the ANSI-specification strike (1-1/4 inch by 4-7/8 inch with dust box) for Grade 1 B600/700 deadbolts. The larger footprint distributes bolt load across more frame material, increasing kick-in resistance. The 10-094 (1-1/8 inch by 2-3/4 inch, no box) is the standard for Grade 2 B500 applications. Use the 10-087 when the specification requires ANSI/BHMA A156.31 strike dimensions or when Grade 1 security level is required. Templates J918 (wood) and J919 (metal).

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Schlage Key Systems Guide: Master Keying, Everest 29, Primus XP, SFIC, FSIC and SL Cylinders Friday, July 10, 2026

A Schlage key system is not just a set of keys and locks. It is an access management architecture that determines who can open which doors, how easily keys can be duplicated or controlled, whether a building can be rekeyed without disassembling every lock, and what happens when a key is lost. Understanding the options before specifying cylinders prevents the two most common and most expensive mistakes: ordering SFIC cores when Grade 1 Security is required, and specifying open keyways when restricted key control is the actual need.

SecurityParts.com carries Schlage cylinders and cylinder-related parts for the full range of Schlage commercial hardware including ND Series and ALX Series cylindrical lock cylinders, L Series mortise lock cylinders, B Series deadbolt cylinders, rim cylinders for Von Duprin exit devices, and all related SFIC and FSIC tailpiece components. Contact the team at 845-935-0301 or the SecurityParts.com contact page for cylinder format and keyway identification support.

How Master Keying Works

The Key Hierarchy: Change Key Through Grand Master Key

A Schlage master key system assigns each cylinder at least two levels of operation. The change key opens only that specific cylinder and no other. The master key opens every cylinder within a defined group. In a building with multiple groups, a grand master key opens all cylinders across all groups. Buildings with multiple buildings or campuses may add a great grand master key above the grand master level.

The pinning of each cylinder accommodates both the change key and the master key by using master pins between the driver pins and the plug pins. The master pin creates a second shear line inside the cylinder at a different position than the standard shear line created by the change key cuts. When the master key is inserted, the master pins align the second shear line with the shear point, allowing the plug to rotate. Each cylinder has a unique change key but shares the master pin arrangement with every other cylinder in its group.

Security Trade-Off: Master Keying Reduces Key Change Combinations

Every level of master keying added to a key system reduces the total number of available key combinations. This is because master pins occupy space in the pin chamber that would otherwise be used for change key pins. The more levels of master keying in the system, the fewer unique change key combinations are available. On a large campus with many master key levels, the number of usable change key combinations can be significantly reduced compared to a non-master-keyed system.

Schlage's Maximum Adjacent Cut Specification (MACS) limits how different adjacent cuts on a key can be, preventing keys that are mechanically difficult to cut or that would allow picking by progressive picking. A properly designed master key system stays within MACS across all key levels. On large systems, a qualified locksmith or key system consultant should design the key system to ensure enough unique combinations are available for the number of openings and key levels needed.

Construction master keying: what it is and why it matters at project completion. Construction keying is a temporary arrangement where all cylinders share a common construction master key during the building phase, allowing contractors, inspectors, and trades to access the building with a single key. At project completion, the construction cylinders are removed and replaced with the permanent key system. Schlage offers disposable plastic construction cores (discarded at turnover) and refundable construction cores (returned for credit). Construction keying is not available for Primus XP cylinders because the factory-milled Primus side bitting is a unique permanent feature that cannot be used as a shared construction key.

The Everest 29 Keyway Family: Open vs Restricted

What Everest 29 Is and Why It Replaced Classic Keyways

Everest 29 is Schlage's current standard keyway family for commercial mechanical cylinders, introduced in August 2012 and patent-protected until 2029. It uses an undercut key design and includes a check pin in the cylinder plug that must align with a notch in the key undercut during key insertion. This check pin provides a level of physical security above the classic Schlage C keyway by making it harder to pick and impossible to use an unmodified legacy key blank in an Everest 29 cylinder.

The Everest 29 family has three sub-families: S, T, and R. All three are backward compatible with the legacy Everest B, C, and D families respectively, meaning a newer Everest 29 key will operate an older legacy cylinder, but an older legacy key will not operate an Everest 29 cylinder.

S Family: Open Keyways for Standard Commercial Applications

Everest 29 S family keyways are open, meaning no authorization is required to purchase key blanks or cylinders. They are available through all Schlage commercial distributors. Key blanks can be cut at any locksmith counter that stocks them. The S family provides the standard Everest 29 security level with the check pin, and all Everest 29 cylinders ship with S123 as the default keyway for stocked products.

Open S keyways are appropriate for building interiors where key control is managed through administrative procedures rather than blank restriction, and for large systems where the volume of keys required makes restricted blanks impractical for daily operations. S family cylinders can be upgraded to Primus XP security at any time by replacing cylinders without replacing keys on the remaining conventional locks.

T Family: Restricted Keyways for Enhanced Key Control

Everest 29 T family keyways are restricted. The end user must sign a letter of authorization, and key blanks and cylinders are drop-shipped directly to the authorized user or an authorized location. T keyways are not stocked at locksmith counters or distribution points. This makes unauthorized key duplication significantly harder than with S keyways, because a person who obtains a T keyway key cannot walk into a locksmith and have it duplicated. T family cylinders provide the same Everest 29 check pin security as S family and can also be upgraded to Primus XP.

R Family: Restricted Keyways for SFIC and SL Systems

Everest 29 R family keyways are used exclusively with SFIC cores and SL cylinders. The R keyway is restricted and is the foundation of a unified three-format key system when SL cylinders are used alongside SFIC cores. The R keyway has the same restriction requirements as the T family but is specifically designed for the A2 pinning style used in 7-pin SFIC cylinders and in the SL conventional and FSIC cylinders that unify the system.

Primus XP: High Security Cylinders and Geographic Exclusivity

How Primus XP Works

Primus XP adds a secondary, independent sidebar mechanism to the standard Everest 29 cylinder. The sidebar requires a factory-milled side bitting on the Primus key to engage a set of finger pins inside the cylinder. The plug can only rotate when both the standard pin tumbler mechanism (operated by the key cuts) and the sidebar mechanism (operated by the side bitting) are satisfied simultaneously. A pick set that defeats the pin tumbler mechanism does not defeat the sidebar, making Primus XP cylinders highly resistant to standard picking and bumping attacks.

Primus keys are factory-milled at the Schlage factory. They are never cut in the field. This means unauthorized key duplication through field cutting is not possible: a locksmith cannot cut a Primus key from a code or from a key impression without the factory authorization for that specific side bitting.

The Five Geographic Exclusivity Levels

The administrative security of the Primus XP system is the geographic exclusivity of the side bitting. Each Primus XP milling is assigned to a user at one of five exclusivity levels:

Zip code exclusivity: The user owns the only Primus XP milling in their zip code. No other institution or locksmith in that zip code can legally obtain that milling.
Area code exclusivity: The milling is exclusive within the user's telephone area code region.
Time zone exclusivity: The milling is exclusive across the user's time zone.
State exclusivity: The milling is exclusive across the entire state.
National exclusivity: The milling is owned exclusively at the national level by a single organization. No other user in the country can obtain this milling.

Higher exclusivity levels require a larger investment and are typically specified by healthcare systems, university campuses, government agencies, and financial institutions where key system integrity is a regulatory or liability requirement.

Primus keys are downward compatible with conventional cylinders. A Primus key will operate a conventional Everest 29 cylinder of the same keyway family. This means a building can be upgraded incrementally: install Primus XP cylinders at the highest-security openings while leaving conventional cylinders elsewhere, and the Primus key opens all of them. This eliminates the need for key system staff to carry separate keys during a phased upgrade, and it means the Primus investment protects the most critical openings without requiring a complete re-keying of the entire facility.

UL 437 Listed Primus XP Cylinders

The highest-security Primus XP cylinders carry a UL 437 listing, meaning they have been independently tested and certified as both pick-resistant and drill-resistant. UL 437 cylinders include hardened steel anti-drill pins in the pin chambers and are specifically tested to resist attack with common picking tools and power drill intrusion. UL 437 is specified by government agencies and high-security facilities where mechanical cylinder resistance to attack is a requirement rather than a preference. Browse Schlage Primus XP cylinder parts at SecurityParts.com.

Cylinder Formats: Conventional, FSIC, SFIC, and SL

Conventional Cylinders

A conventional cylinder is installed permanently in the lock body and can only be rekeyed by removing it from the lock and repinning the plug. This requires disassembling the lock or at least removing the cylinder from the lock case, which takes a few minutes per opening. Conventional cylinders maintain the full ANSI security grade of the lock, including Grade 1 Security when used with Schlage ND Series or L Series hardware. They are available in Everest 29 S and T open and restricted keyways and can be upgraded to Primus XP at any time.

FSIC: Full Size Interchangeable Core

FSIC (Full Size Interchangeable Core) cylinders use a control key to remove the entire cylinder core from the lock body in seconds without any disassembly. A new core with a different key combination can be inserted in the same motion. This makes rekeying an FSIC system dramatically faster than a conventional system on large facilities. The Schlage FSIC format is Schlage-proprietary: it is not cross-manufacturer interchangeable. With FSIC cylinders, the Schlage ND or L Series lock is ANSI Grade 1 Operational and Grade 2 Security. Browse Schlage FSIC tailpiece and cylinder parts at SecurityParts.com.

SFIC: Small Format Interchangeable Core

SFIC (Small Format Interchangeable Core) uses the Best/Arrow standard plug format that originated in the mid-twentieth century as an industry-standard format adopted across many manufacturers. A control key removes the SFIC core from the lock in seconds, the same as FSIC, but the SFIC core is interchangeable across brands. This means an SFIC-based facility can change lock brands without replacing cylinders, and service shops with SFIC tooling can service any brand's SFIC hardware with the same equipment.

The SFIC security grade reduction that most specifiers miss. When SFIC cylinders are installed in a Schlage ND Series or L Series lock, the complete assembly is ANSI Grade 1 Operational but only Grade 3 Security. The SFIC format's cross-manufacturer interchangeability comes at a security cost that is published in Schlage's ANSI/BHMA certification data but is almost never explained at the point of sale. A facility that specifies SFIC for rekeying convenience on a Grade 1 specified project may be delivering a Grade 3 Security installation without knowing it. Specifiers who need Grade 1 Security across the complete assembly must use conventional, FSIC, or SL cylinders, not SFIC.

SL: The Three-Format Unifier

The Schlage SL cylinder is the solution to the most common key system problem on large campuses: a mix of lock brands and cylinder formats that cannot share a single key system. SL cylinders are available in conventional and FSIC formats but are keyed with the 7-pin A2 pinning style used in Schlage SFIC cylinders. This means SL conventional and FSIC cylinders share the same Everest 29 R keyway family as SFIC cores.

The practical result: an SFIC-based campus can add SL conventional cylinders in locks that require a non-SFIC format (mortise locks, certain hardware configurations, rim applications) without creating a second separate key system. Every opening on the campus operates on the same key. SL cylinders also support Primus XP geographic exclusivity and maintain Grade 1 Security, resolving the SFIC security grade problem for mixed-format campuses. This is the specification detail that makes the difference between a unified campus key system and a fragmented one with multiple key sets.

SL cylinder backward compatibility note: Everest 29 R restricted keyway SL cylinders in both conventional and FSIC formats are upgradeable to Primus XP. Legacy Everest B keyways can also be upgraded to Primus XP through SL cylinders in 7-pin conventional and FSIC formats. The upgrade path preserves key system continuity without requiring a complete facility re-key.

Choosing the Right Key System for Your Building

Small Building or Single Tenant: Conventional Open Keyway

A single-tenant office building, small retail location, or single-floor facility typically does not need restricted keyways or interchangeable cores. A conventional Everest 29 S family cylinder provides the check pin security of the Everest 29 family and the full Grade 1 Security of the Schlage ND or L Series lock. Rekeying requires removing cylinders, which is infrequent in a stable single-tenant environment. This is the lowest-cost configuration with the highest ANSI security grade.

Medium Building with Tenant Turnover: FSIC or Restricted Conventional

A mid-size office building with multiple tenants, a multifamily residential property with regular unit turnover, or a healthcare clinic with staff changes benefits from either FSIC cylinders (for fast rekeying without disassembly) or restricted conventional cylinders in T family keyways (for key control without the investment in interchangeable core infrastructure). FSIC allows a facilities manager to rekey an entire floor in an afternoon without a locksmith. Restricted T family keyways prevent former tenants or staff from duplicating their keys.

Large Campus or High Security: Primus XP with FSIC or SL

A university campus, hospital system, government building, or any facility where key system integrity is a regulatory or liability requirement should specify Primus XP cylinders at critical openings with FSIC or SL cylinders at standard openings. The Primus side bitting provides factory-controlled key duplication and geographic exclusivity at critical points. The FSIC or SL format allows fast rekeying across the standard openings. SL cylinders unify the key system if the campus has a mix of SFIC and non-SFIC hardware.

SFIC Campus with Mixed Hardware: SL as the Unifier

An SFIC-based campus that adds locks requiring conventional or FSIC format cylinders should specify SL cylinders for those openings rather than creating a second key system. SL cylinders share the Everest 29 R restricted keyway with SFIC cores, maintain Grade 1 Security, and support Primus XP upgrade paths. The entire campus operates on a single key, which simplifies key management, reduces key ring size, and eliminates the access issues that arise when staff carry multiple keys for different areas of the same facility.

Why Choose SecurityParts.com for Schlage Cylinder Parts

SecurityParts.com documents the SFIC security grade reduction from Grade 1 to Grade 3 that most parts suppliers never explain, the SL cylinder as the three-format unifier for mixed campuses, the Primus XP five geographic exclusivity levels, and the construction keying options available for each cylinder format. This level of cylinder specification knowledge means you can call 845-935-0301 and get the right cylinder format and keyway confirmed before the order is placed, not after a wrong-part return.

Browse Schlage ND Series cylindrical lock cylinder and tailpiece parts, Schlage L Series mortise lock cylinder parts, Schlage rim cylinders for Von Duprin exit devices, and Schlage B Series deadbolt cylinder parts. Contact the team at 845-935-0301 or the SecurityParts.com contact page for key system and cylinder specification support.

Frequently Asked Questions About Schlage Key Systems

How does a Schlage master key system work?

Each cylinder is pinned with master pins that create a second shear line in addition to the standard shear line. The change key aligns the standard shear line and opens only that cylinder. The master key aligns the second shear line created by the master pins and opens every cylinder in the group. A grand master key adds a third level that opens all cylinders across all groups. Each additional master key level reduces the total number of available unique change key combinations because master pins occupy space in the pin chambers.

What is the difference between Everest 29 S, T, and R keyways?

S family: open keyways, no authorization required, available at all distributors. T family: restricted keyways, authorization required, key blanks drop-shipped directly to the authorized user, not available at locksmith counters. R family: restricted keyways used exclusively with SFIC cores and SL cylinders, sharing the Everest 29 R keyway across all three cylinder formats when SL unification is used. All three are backward compatible with the corresponding legacy Everest B, C, and D families respectively.

What is the Schlage Primus XP cylinder and what does geographic exclusivity mean?

Primus XP adds a secondary independent sidebar mechanism that requires a factory-milled side bitting on the key in addition to the standard key cuts. Both mechanisms must be satisfied simultaneously for the plug to rotate. Geographic exclusivity means each Primus milling is assigned to one user at one of five levels (zip code, area code, time zone, state, or national). At zip code exclusivity, no other institution or locksmith in that zip code can obtain the same milling. Primus keys are factory-milled only, never cut in the field.

What is the difference between SFIC and FSIC cylinders and which should I specify?

SFIC uses the cross-manufacturer Best/Arrow standard plug format. FSIC uses the Schlage-proprietary larger plug format. Both remove with a control key in seconds for fast rekeying. The critical difference: SFIC reduces the complete assembly to ANSI Grade 3 Security even though the lock body is Grade 1. FSIC reduces to Grade 2 Security. Conventional and SL cylinders maintain Grade 1 Security. Specify SFIC only where fast rekeying speed across multiple brands is required and Grade 3 Security is acceptable. Specify FSIC or SL where fast rekeying is needed and Grade 1 or Grade 2 Security must be maintained.

What is the Schlage SL cylinder and how does it unify a mixed key system?

The SL cylinder is available in conventional and FSIC formats but uses the 7-pin A2 pinning style of SFIC cylinders, sharing the Everest 29 R keyway family across all three formats. An SFIC-based campus can add SL conventional or FSIC cylinders where non-SFIC format is required without creating a second key system. All openings operate on the same key. SL maintains Grade 1 Security and supports Primus XP geographic exclusivity, resolving both the mixed-format and the SFIC security grade problems simultaneously.

What is construction keying and how does it work on a Schlage system?

Construction keying assigns all cylinders a temporary common construction master key during the building phase so contractors can access all openings with one key. At project completion the construction cylinders are replaced with the permanent key system. Schlage offers disposable plastic construction cores and refundable construction cores. Construction keying is not available for Primus XP cylinders because the factory-milled Primus side bitting is a unique permanent feature that cannot serve as a shared construction key.

Are Everest 29 keyways backward compatible with older Everest keyways?

Yes, but only in one direction. Everest 29 S, T, and R keys operate the corresponding legacy Everest C, D, and B cylinders respectively. However, legacy Everest C, D, and B keys will not operate Everest 29 cylinders. The check pin in the Everest 29 cylinder plug prevents legacy keys from rotating the plug. This one-directional compatibility means an upgrade from legacy to Everest 29 requires replacing cylinders, but existing keys for the remaining legacy cylinders continue to work until those cylinders are also upgraded.

What cylinders does SecurityParts.com carry for Schlage locks?

SecurityParts.com carries Schlage cylinders and cylinder-related parts for ND Series cylindrical locks, L Series mortise locks, B Series deadbolts, AD Series and CO Series electronic locks, padlocks, and cabinet locks. This includes conventional Everest 29 S and T cylinders, SFIC cores, FSIC cores, and tailpieces for interchangeable core configurations. Rim cylinders for Von Duprin exit devices in straight cam applications are also available. Contact SecurityParts.com at 845-935-0301 for cylinder format and keyway specification support.

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Schlage CS210 Interconnected Lock, HL6 Hospital Latch and THP Tubular Lock Parts: Complete Guide Friday, July 10, 2026

Security Parts carries parts for the Schlage CS210 Series interconnected lock (lever kit 06-242, Plymouth rose 08-029-PLY, Saturn rose 08-029-SAT, strike combinations 10-109 and 10-121, deadbolt strike 10-116), the Schlage HL6 Series hospital push-pull latch (mortise and tubular paddle assemblies, engraved and non-engraved, bent tab mortise strike kit), and the Schlage THP/LT Series tubular lock latches (THP-8201 spring latch, THP-8219 privacy latch, fire-rated versions with -F suffix). The CS210 B500 supports SFIC; the B60 does not. The HL6 key override anti-barricade function is available on three functions and is the critical safety feature for behavioral health environments.

Three Schlage product lines cover the doors that standard cylindrical and mortise locks do not. The CS210 interconnected lock addresses the NFPA 101 single-motion egress requirement on multifamily apartment entries where both a deadbolt and latch are required. The HL6 hospital latch addresses healthcare corridor doors where staff need hands-free operation and 50 percent quieter paddle action. The THP and PT Series tubular latches provide the latch assemblies that keep interior residential and light commercial doors functioning correctly. Each line has specific parts requirements and ordering decisions that differ from standard cylindrical lock parts.

Browse the complete CS210 interconnected lock parts catalog, HL6 hospital latch lock parts catalog, and tubular lock parts catalog at SecurityParts.com. For the full Schlage commercial hardware range, browse the Schlage commercial hardware catalog.

Grade 2 ANSI/BHMA certification on CS210, exceeding Grade 2 for cycle, security, and finish

50% quieter HL6 redesigned paddle operation vs previous HL Series hospital latch

3-hour UL fire door rating on CS210 and HL6 mortise versions

SFIC CS210 B500 only supports SFIC cylinders: B60 residential housing does not

Schlage CS210 Interconnected Lock: What It Is and Why It Exists

The Schlage CS210 is a Grade 2 interconnected lock designed exclusively in the CS210 entrance function (B500 commercial or B60 residential deadbolt housing with single-cylinder entry). The interconnected design solves a specific code problem on multifamily residential doors: building codes and NFPA 101 require that doors on means of egress can be opened in a single motion from the inside. When a door has both a separate deadbolt and a separate latch lock, the occupant must turn the deadbolt and then the latch lever separately to exit. That is two motions, which does not comply with single-motion egress requirements.

The CS210's mechanical link between the deadbolt and latch bolt resolves this: turning the inside lever once retracts both simultaneously. The exterior side maintains normal security: the deadbolt requires a key, the latch requires a lever. But from the inside, one motion provides immediate egress regardless of whether the deadbolt is locked.

Why interconnected locks are required in some jurisdictions and optional in others: NFPA 101 Section 7.2.1.5 requires that locks on doors on egress paths not require more than one releasing operation. Some local jurisdictions apply this requirement specifically to apartment and dwelling unit entry doors in addition to primary egress stairwells and corridors. This is why some municipalities require interconnected locks on apartment entry doors while neighboring municipalities allow separate deadbolts and latches. When interconnected locks are required by local code or AHJ interpretation on a multifamily project, the CS210 is the correct Schlage specification. Substituting separate deadbolt and latch hardware on these applications creates a code-non-compliant installation regardless of the hardware quality.

CS210 Specifications and Key Technical Details

Deadbolt and Latch Dimensions

The CS210 deadbolt is a 1-inch throw with a 1-inch diameter housing. The faceplate is dual option (square corner standard, round corner included in the package), 1 inch by 2-1/4 inches. The deadbolt requires a 1-inch edge bore.

The latch bolt is 1-5/8 inch by 2-1/4 inch with a dual option faceplate. The backset is adjustable and fits both 2-3/8-inch and 2-3/4-inch door preparations, eliminating the need to specify backset at order time for most standard door configurations.

Adjustable Escutcheon for 4-Inch and 5-1/2-Inch Door Preps

The CS210 includes an adjustable escutcheon that supports either 4-inch or 5-1/2-inch center-to-center door preparations from the same unit. This is an underappreciated practical specification advantage on multifamily renovation projects where existing doors may have been prepared for different center-to-center dimensions by different manufacturers over decades of construction. The single adjustable escutcheon eliminates the need to specify the exact existing door prep at the time of order, reducing re-order rates on renovation projects where the existing door prep has not been documented.

Door Thickness Range

The CS210 accommodates standard door thicknesses of 1-3/4 inches to 2 inches. The 1-3/8-inch door thickness version is available but must be specifically noted at the time of ordering. Most commercial and multifamily doors are 1-3/4 inches, so the standard version covers the majority of applications. When the CS210 is specified for older wood-frame residential construction where 1-3/8-inch doors remain common, the thinner door specification must be confirmed before ordering.

Cylinder Options and the SFIC Limitation

The CS210 is available with conventional 6-pin cylinders (standard S123 keyway, keyed different), Full Size Interchangeable Core (FSIC) cylinders, and Small Format Interchangeable Core (SFIC) cylinders. The choice matters for key system management.

SFIC cylinders allow the core (the inner cylinder with the keyway and pins) to be exchanged in the field in seconds without any tools or disassembly of the lock. This rapid core exchange makes SFIC the preferred choice for high-security institutional applications where rekeying must be completed quickly after a key loss event.

The SFIC limitation on the CS210 B60 that creates a key system conflict: SFIC cylinders are not available with the B60 residential cylinder housing assembly on the CS210. Only the B500 commercial cylinder housing supports SFIC. This creates a specification conflict when a multifamily project uses Schlage SFIC throughout the building (common in healthcare, student housing, and government multifamily projects) and the specifier orders the B60 version of the CS210 to save cost. The B60 doors cannot be incorporated into the SFIC key schedule, producing a two-key-system building where the same facility master key cannot open apartment doors. Confirm the cylinder type requirement before specifying B60 versus B500 on any SFIC key system project.

CS210 Parts Reference

06-242 CS210 Series Lever Kit

Lever Replacement | All CS210 Levers

Replacement lever kit for the CS210 interconnected lock. Used when replacing or updating lever trim on an existing CS210 installation. Required when lever is damaged, finish is mismatched, or lever style is being changed on a renovation project. Compatible with all CS210 chassis assemblies manufactured after December 2010.

08-029-PLY | 08-029-SAT Rose

Plymouth and Saturn Rose Designs

Decorative rose plate for the CS210 interconnected lock in PLY (Plymouth) and SAT (Saturn) designs. Mounts between the lever and door face. When rose is damaged or finish does not match the lever, the 08-029 in the correct style and finish is the replacement. Confirm the outside chassis assembly compatibility before ordering rose only.

10-109 CS210 Strike Combination

Deadbolt + Deadlatch Strike Set

Strike combination set for the CS210 including both the deadbolt strike and the deadlatch strike required for a complete CS210 installation. The CS210 uses two strikes (one for the deadbolt, one for the latch) at specific center-to-center dimensions. Never substitute with a single strike for either bolt: the interconnected mechanism requires both strikes to be correctly positioned for reliable deadbolt and latch engagement on every door closure.

10-121 CS210 Strike Combination

Alternate Strike Combination

Alternate CS210 strike combination for door preps that use the 5-inch backset configuration. Not all CS210 installations use the standard strike combination. When ordering a CS210 strike replacement, confirm which door prep configuration is installed before selecting between 10-109 and 10-121.

10-116 Deadbolt Strike

1-1/8" x 2-3/4" Round Corner | No Lip

Round corner deadbolt strike, 1-1/8 inch by 2-3/4 inch, no lip. Individual deadbolt strike for CS210 installations where only the deadbolt strike requires replacement. Used when the deadbolt strike is damaged or missing but the latch strike is intact. Always confirm corner style (square vs round) before ordering any individual strike replacement.

The two-strike alignment fact that generates most CS210 latch complaints: The CS210 uses two separate strikes mounted at specific center-to-center spacing on the door frame. When one strike is replaced without confirming the other strike's position, the center-to-center relationship between the two strikes changes. The CS210's interconnected mechanism requires both the deadbolt bolt and the latch bolt to engage their respective strikes simultaneously on door closure. If the strikes are misaligned relative to each other, the lock can appear functional (both bolts extend) but the door does not latch or deadlock correctly because one bolt engages before the other does. When replacing any CS210 strike, verify the center-to-center dimension of the strike pair matches the CS210 parts manual specification.

Schlage HL6 Hospital Latch: Parts and Critical Design Features

The Schlage HL6 is not a cylindrical lock or mortise lock in the conventional sense. It is a push-pull latch designed specifically for healthcare environments where the operating format of standard levers is inadequate. A lever requires a gripping and rotating motion. A paddle requires only a push or pull with any part of the body including elbow, forearm, hip, or foot. This hand-free operation capability is not optional on many healthcare door applications: infection control protocols in ICU, surgical, and isolation environments prohibit hand contact with door hardware except through gloves.

HL6 Versions: Mortise vs Tubular

The HL6 Series comes in both mortise and tubular body versions. The mortise version uses the Schlage L Series chassis and mortise door preparation, providing superior strength and the full range of function options. The tubular version uses a standard tubular bore preparation, making it retrofittable to existing hollow-core residential-style doors in renovation applications without requiring a mortise pocket.

Parts at SecurityParts.com for the HL6 include cover assemblies (the decorative cover over the latch body), mortise paddle assemblies (engraved and non-engraved), tubular paddle assemblies (engraved and non-engraved), and the bent tab mortise strike kit for the mortise version.

Engraved vs Non-Engraved Paddle Assemblies

The HL6 paddle assembly is available in two surface finishes: non-engraved (smooth paddle face) and engraved (textured or marked paddle face). The engraved version provides a tactile surface and is required by some healthcare facility infection control standards that specify textured surfaces on frequently touched hardware to reduce smooth-surface pathogen transfer. The non-engraved version is appropriate for facilities that prefer a smooth aesthetic surface or where the engraved texture is not specified.

When replacing a paddle assembly on an existing HL6 installation, confirm whether the existing paddle is engraved or non-engraved before ordering, since both types are available in the parts catalog at the same product positions but are distinct assemblies.

The 50 Percent Quieter Redesign

Schlage redesigned the HL Series to achieve 50 percent quieter paddle operation compared to the previous product. This noise reduction is a documented clinical benefit: hospital noise levels directly correlate with patient recovery outcomes and staff performance accuracy in multiple clinical studies. Door hardware noise in patient corridors is a contributor to the ambient noise environment that regulatory standards (specifically ANSI/ASA S12.60 and Joint Commission environment of care standards) measure and regulate.

When replacing a paddle on an existing HL6 installation, the replacement paddle assembly from the current parts catalog carries the quieter design. If the facility is replacing older pre-redesign HL Series hardware with current HL6 parts, the noise level reduction is a verifiable improvement that can be documented for Joint Commission environmental surveys.

The lead-lining option that most specification writers miss: The Schlage HL6 mortise version is available with a 1/8-inch thick lead-lined lock case for use in X-ray rooms and other areas with radiation concern. Radiation-controlled environments in hospital imaging departments, radiotherapy suites, and diagnostic imaging rooms require that all wall penetrations and door hardware maintain the required radiation shielding of the surrounding wall construction. A standard latch body in a radiation-controlled door creates an unshielded penetration. The HL6 with lead-lined lock case maintains the door's radiation shielding continuity at the latch location. This option is not described in any general-purpose hardware specification guide and is absent from all competitor parts supplier content. Facilities specifying hardware for radiation-controlled environments should verify this option is available and specify it explicitly.

Key Override Anti-Barricade Function

The HL6 optional key override allows an outside key to retract the latch or deadbolt even when the inside thumbturn is actively held in the locked position. This function exists specifically for behavioral health and psychiatric care environments where a patient may use the inside thumbturn to prevent staff from entering during a self-harm event or mental health crisis.

Standard locks (including standard mortise and cylindrical locks) cannot be opened from the outside when the inside thumbturn is being held. A patient who turns the thumbturn and holds it effectively barricades the room. The HL6 key override breaks this barricade without requiring staff to force the door. Available on three HL6 functions. This is a joint healthcare design requirement that involves input from clinical staff, risk management, and facility management on any behavioral health project.

HL6 Parts Reference

Part	Description	When to Order
HL6 Series Cover Assembly	Decorative cover over latch body	Cover damage, finish mismatch, or renovation update
HL6 Mortise Engraved Paddle Assembly	Textured surface paddle for mortise HL6	Paddle replacement on mortise HL6 where engraved surface is specified
HL6 Mortise Paddle Assembly (Non-Engraved)	Smooth surface paddle for mortise HL6	Paddle replacement on mortise HL6 where smooth surface is preferred
HL6 Tubular Engraved Paddle Assembly	Textured surface paddle for tubular HL6	Paddle replacement on tubular HL6 where engraved surface is specified
HL6 Tubular Paddle Assembly (Non-Engraved)	Smooth surface paddle for tubular HL6	Paddle replacement on tubular HL6 where smooth surface is preferred
Bent Tab Mortise Strike Kit	Strike kit for HL6 mortise version	Strike replacement on HL6 mortise installations; door frame rework

Schlage THP and PT Series Tubular Lock Latches

The Schlage THP (Tubular Hardware Product) and PT Series latches are the latch assemblies used in the Schlage LT Series decorative tubular locks and related families. These are not complete locks: they are the latch component that installs in the edge bore and provides the spring-loaded bolt that holds a door closed. When the lever or knob is turned, it activates the latch to retract the bolt.

THP-8201 Spring Latch: Standard Passage Latch

The THP-8201 is a spring latch (passage function) for tubular lock installations. It is the most commonly replaced tubular latch component because the latch bolt is subject to direct physical stress on every door cycle: the bolt must retract on lever operation and spring back to extended position when the lever is released. Over years of high-cycle use, the spring loses tension and the bolt may not fully extend, causing the door to not latch reliably.

The THP-8201-CH uses a 2-3/8-inch backset (standard for interior residential and light commercial doors). The fire-rated version is THP-8201-CH-F. The THP-8301-CH uses a 2-3/4-inch backset (standard for commercial doors). Ordering the wrong backset produces a latch that extends to the wrong position for the strike, causing either the door not latching or the latch hitting the strike face rather than engaging the strike pocket.

THP-8219 Privacy Latch: Anti-Lockout Design

The THP-8219 is a privacy latch with a restoring function that prevents accidental lockouts. In standard privacy sets (bathroom and bedroom locks), the inside push button or thumbturn locks the outside lever. If the inside button is accidentally pressed and the door closes, the occupant is locked out. The privacy latch restoring function means the privacy mechanism automatically releases when the door is opened from the inside, requiring the privacy lock to be deliberately re-engaged on each use.

The THP-8219-CH uses a 2-3/8-inch backset. The fire-rated version is THP-8219-CH-F. The 2-3/4-inch backset version is THP-8319-CH. When ordering any THP-8219 replacement, measure the backset of the existing latch before ordering. The same door that uses THP-8201-CH for passage will use THP-8219-CH for privacy, matching backsets throughout a project.

Backset Selection: The Only Critical Measurement

The backset is the single measurement that determines which THP latch to order. It is measured from the edge of the door (where the latch bolt projects) to the center of the cylindrical bore hole in the door face. Two standard backsets exist:

2-3/8 inch (THP-8201-CH, THP-8219-CH): Standard for interior residential and light commercial doors. Interior hollow-core doors in apartments, hotel rooms, offices, and classrooms typically use 2-3/8-inch backset.

2-3/4 inch (THP-8301-CH, THP-8319-CH): Standard for heavier commercial doors including hollow metal and solid wood commercial doors. Most commercial lever lock installations on 1-3/4-inch hollow metal doors use 2-3/4-inch backset.

The backset measurement that prevents a return on every THP latch order: Measure the backset before removing the existing latch. With the door in the closed position, measure from the face of the door edge (the narrow edge) to the center of the bolt. Do not remove the latch first and then try to measure the empty bore hole: the hole center is harder to locate accurately without the latch body present. Two minutes with a tape measure before starting the replacement eliminates the most common THP latch wrong-size return.

Fire-Rated THP Latches

Fire-rated versions of THP latches add the -F suffix: THP-8201-CH-F and THP-8219-CH-F. Fire-rated latches are required on doors with UL-listed fire door assemblies. The fire-rated latch uses materials and construction that maintain the latch function under the elevated temperature conditions of a fire event, preventing the latch from failing prematurely and allowing the door to remain latched (providing the fire separation) longer than a standard latch would under fire conditions. Installing a standard non-fire-rated latch in a fire-rated door assembly invalidates the UL listing of the assembly.

LT Series Tubular Locks: Coordinated Appearance with L Series

The Schlage LT Series tubular lock is designed specifically to match the appearance and lever family of the Schlage L Series mortise lock. This is a significant specification detail for projects where some doors use L Series mortise locks (high-security entries, stairwells, main corridors) and other doors use lighter-duty tubular hardware (utility rooms, storage, interior corridors). Matching the lever design, finish, and rose style across both series creates visual consistency throughout the building that is otherwise impossible when mixing hardware families.

The LT Series uses the same lever designs as the L Series, manufactured from solid brass or solid stainless steel for the same weight and feel as the mortise hardware. Levers move both up and down (not just down as on many tubular locks), matching the bidirectional lever operation of the L Series. The inside lever operates independently from the outside lever, providing a higher-end operation where inside lever movement does not affect the outside lever position.

When the LT Series is specified as part of an L Series project, THP latch parts ordered for the LT Series should match the backset, latch function, and fire-rating requirements of the door the LT Series lock is installed on. The THP latch is the only replacement component needed for most LT Series service calls because the LT Series chassis and lever are robust enough to outlast the latch spring in most commercial applications.

Browse the complete CS210 interconnected lock parts, HL6 hospital latch parts, and tubular lock parts at SecurityParts.com. For the broader Schlage hardware range including ND Series cylindrical lock parts, L Series mortise lock parts, B Series deadbolt parts, and CL Series cabinet lock parts, browse the Schlage commercial hardware catalog. Pre-order support is at 845-935-0301 or the contact page.

Why Choose SecurityParts.com for CS210, HL6 and THP Parts

Single-motion egress code context, SFIC B60 limitation warning, HL6 lead-lining option, key override anti-barricade, backset measurement guidance, and same-day shipping.

Single-Motion Egress Code

We document why CS210 interconnected locks are required by some jurisdictions and the specific NFPA 101 section that creates this requirement. No other parts supplier explains the code driver for interconnected locks.

HL6 Lead-Lining Option

We document the HL6 lead-lined lock case option for radiation-controlled environments. This specification detail is absent from all buyer-facing hardware content and from every competitor parts supplier page.

Key Override Safety

We document the HL6 key override anti-barricade function and the behavioral health design requirement it addresses. This feature prevents patient-initiated barricade events in psychiatric and behavioral health facilities.

Same-Day Shipping

Most CS210, HL6, and THP parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for backset, function, and cylinder type support.

What Makes SecurityParts.com Different for These Schlage Parts

We document the CS210 SFIC cylinder limitation: SFIC is not available with the B60 residential housing, only B500 commercial. This prevents the key system conflict on SFIC multifamily projects where B60 is ordered to save cost and then cannot be incorporated into the building SFIC schedule.
We document the CS210 two-strike alignment requirement and why misaligned strikes generate latch complaints even when both strikes are replaced. Center-to-center positioning of the two CS210 strikes is a specification detail absent from all parts supplier content.
We document the HL6 lead-lined lock case option for radiation-controlled environments. No other parts supplier documents this at the product level. Radiation-controlled hospital rooms without lead-lined hardware have unshielded penetrations through the door at the latch location.
We document the HL6 key override anti-barricade function and the behavioral health design requirement it addresses. This is the most important HL6 function specification for psychiatric and behavioral health projects and is not documented in any competitor parts page.
We carry CS210, HL6, and THP parts alongside ND Series cylindrical lock parts, L Series mortise lock parts, B Series deadbolt parts, and LCN door closer parts for complete door hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

CS210, HL6, and THP locks appear alongside standard cylindrical locks, deadbolts, and door closers throughout commercial and healthcare facilities. Most building service calls cover multiple lock product lines simultaneously.

For Schlage ND Series and ALX Series cylindrical lock parts on secured corridor doors in the same building, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on main entries and high-security doors, browse the mortise locks catalog. For Schlage B Series deadbolt parts on secondary exits in the same facility, browse the deadbolts catalog. For Schlage CL Series cabinet lock parts on medication storage and filing cabinets in the same key system, browse the cabinet locks catalog. For LCN door closer parts on fire-rated corridor doors in the same building, browse the door closers catalog.

Browse the complete all products and parts catalog to source Schlage, Von Duprin, LCN, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Schlage CS210, HL6 and THP Parts

What is the Schlage CS210 interconnected lock and how does single motion egress work?

The CS210 is a Grade 2 interconnected entrance lock where the deadbolt and latch bolt are mechanically linked. Turning the inside lever once simultaneously retracts both the deadbolt and latch, providing single-motion egress as required by NFPA 101. From the outside, the deadbolt requires a key and the latch requires a lever. Available in B500 commercial and B60 residential cylinder housings, with SFIC available only on the B500 version.

What are the CS210 lever kit 06-242 and rose 08-029 used for?

The 06-242 is the lever replacement kit for the CS210 chassis. The 08-029 is the rose plate in Plymouth (PLY) or Saturn (SAT) design. Both are used when replacing or updating lever trim on an existing CS210 installation. If the outside chassis is not compatible with the current rose, the F206-496 outside chassis assembly may also need updating alongside the 06-242 lever and 08-029 rose.

What is the SFIC cylinder limitation on the Schlage CS210 B60 version?

The CS210 B60 residential cylinder housing does not support SFIC cylinders. Only the B500 commercial housing supports SFIC. When a facility uses Schlage SFIC throughout the building (common in healthcare, education, and government), apartment entry doors must use the B500 commercial CS210 rather than the B60 to allow incorporation into the SFIC key schedule.

What is the Schlage HL6 hospital latch and why does it use a paddle instead of a lever?

The HL6 is a hospital push-pull latch for healthcare environments requiring hands-free door operation. The paddle can be operated with a hand, elbow, forearm, or hip without gripping, supporting infection control protocols where hand contact with door hardware is restricted. Available in mortise (L Series chassis) and tubular versions, both 50 percent quieter than the previous HL Series. Available with optional key override anti-barricade function and optional lead-lined lock case for radiation-controlled rooms.

What is the HL6 key override anti-barricade feature and when is it specified?

The key override on the HL6 allows an outside key to retract the latch or deadbolt even when the inside thumbturn is being actively held in the locked position. This anti-barricade feature is specified in behavioral health and psychiatric environments where a patient may use the thumbturn to prevent staff entry during a self-harm event. Available on three HL6 functions. Without this feature, a patient holding the thumbturn creates a barricade that cannot be opened without forcing the door.

What is the difference between THP-8201 and THP-8219 and how do I select the correct backset?

THP-8201 is a spring latch (passage function). THP-8219 is a privacy latch with a restoring function that prevents accidental lockouts. The backset is the distance from the door edge to the center of the bore hole: THP-8201-CH and THP-8219-CH use 2-3/8-inch backset; THP-8301-CH and THP-8319-CH use 2-3/4-inch backset. Measure the existing backset before removal to confirm the correct size before ordering. Fire-rated versions add the -F suffix.

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Commercial Door Hardware Maintenance Checklist: Monthly, Quarterly, and Annual Tasks Every Facility Manager Needs Thursday, July 9, 2026

Every commercial building has a maintenance schedule for HVAC, plumbing, and electrical systems. Door hardware almost never makes that list until something goes wrong. A door that will not latch during a fire drill, a closer that slams hard enough to break the door frame, or an electric strike that stops responding to the access panel at 6 AM are all symptoms of the same problem: deferred maintenance on hardware that is used hundreds of times every single day.

This guide gives facility managers, property owners, and maintenance teams a structured, code-informed checklist for every piece of commercial door hardware. It covers monthly visual tasks, quarterly mechanical checks, and the annual NFPA 80 inspection that is legally required for every fire-rated door assembly in the building.

What This Guide Covers

This checklist applies to the most common categories of commercial door hardware:

Exit devices and panic bars
Door closers
Electric strikes and access control hardware
Mortise locks and cylindrical locks
Deadbolts
Door frames, hinges, and clearances

Each section connects the inspection task to the specific failure mode it prevents and to the replacement components that resolve it when they are needed.

Why Door Hardware Maintenance Is a Legal Requirement, Not Just Good Practice

NFPA 80 and the Annual Inspection Mandate

NFPA 80, the Standard for Fire Doors and Other Opening Protectives, requires annual inspection of every fire door assembly in a commercial building. That requirement has been in the code since the 2007 edition. The 2022 edition is currently the most widely adopted, and the 2025 edition is the latest published version.

"Annual" under NFPA 80 means a minimum of 9 months and a maximum of 15 months between inspections. That window does not mean inspections are flexible indefinitely. It means the scheduling tolerance is 15 months, not 12. Any facility that goes beyond 15 months without a documented inspection is in violation.

The inspection must be performed by a qualified person, meaning someone with the knowledge, training, and experience to evaluate the assembly correctly. NFPA 80 Section 5.2.3.3 classifies conditions that prevent a fire door from closing or latching as immediate hazards requiring correction before the inspector leaves the site.

Documentation Requirements That Protect the Building Owner

Inspection records must be signed by the inspector and retained for at least 3 years. Healthcare facilities under CMS oversight follow a stricter enforcement path. CMS K-tag K0223 specifically covers fire door deficiencies in Life Safety Code surveys and is consistently among the most-cited compliance tags in hospital inspections.

If an AHJ or insurer audits the building and there are no signed inspection records, the legal exposure falls on the building owner. The documentation is not bureaucratic paperwork. It is the only evidence that compliance happened.

The Real Cost of Non-Compliance

A fire marshal has the authority to revoke a building's certificate of occupancy for non-compliant fire doors. Studies on fire door inspections consistently find that the majority of doors inspected in commercial facilities have at least one deficiency. Common reasons include closer adjustment drift, excessive door clearance gaps, worn latching hardware, and unauthorized modifications to the door assembly that void the listing.

The Monthly Visual Inspection Checklist

Monthly inspections take 2 to 3 minutes per door. They do not require tools, disassembly, or formal documentation. Their purpose is catching problems early so that repairs happen during normal maintenance cycles rather than emergency service calls.

Exit Devices and Panic Bars

Check that the push bar or push pad moves freely and returns to the neutral position without sticking. Confirm that the latch bolt retracts fully when the bar is pressed. Inspect the end caps for cracking or separation. Look for any visible damage to the device body or push bar that would suggest forced entry or misuse.

If the push bar is stiff or the device is not latching reliably, the dogging assembly or the latch return spring is likely worn. Both are model-specific replacement parts. The Von Duprin 98/99 Series parts catalog at Security Parts is organized by model and configuration so the correct component can be identified before the order is placed.

Confirm that fire-rated exit devices showing the "-F" suffix in the model number are not being held open by wedges, blocks, or zip ties. A mechanically dogged fire door is an NFPA 80 violation and an immediate hazard under Section 5.2.3.3.

Door Closers

Observe the closing cycle from the fully open position. The door should move smoothly from open to closed, with the latch bolt engaging the strike without assistance. A door that slams in the final 12 degrees has an incorrectly adjusted latch speed valve. A door that drifts open before fully closing has a weakened spring or a parallel arm connection that has loosened.

Check the closer body and arm connection for visible fluid leaks. A door closer that is leaking hydraulic fluid will develop inconsistent closing behavior as the fluid level drops. LCN closers are sealed at the factory and are not field-refillable. A leaking unit requires replacement or a cylinder assembly swap. See the LCN door closer parts catalog for series-specific components.

Inspect the arm casting at the pivot points for cracking. A cracked arm is one of the most common closer failures in high-traffic corridors and is almost always caused by someone propping the door against the arm or forcing the door open past the backcheck position. The arm is a replaceable component on every LCN series without replacing the entire closer body.

Electric Strikes and Access Control Hardware

Test each electric strike by presenting a valid credential and pulling the door. The release should be immediate with no hesitation or partial engagement. If the keeper re-latches before the door fully opens, the access control system's unlock duration may be too short for the speed at which the door is being used. This is a timing mismatch, not a hardware failure, but it causes keeper plate wear over time if not corrected.

Inspect the strike body face for visible damage, misalignment, or debris in the latch pocket. Check the wiring connection at the strike body for any signs of strain or corrosion on the terminals. The electric strike parts at Security Parts cover Von Duprin 5100, 6100, 6200, and 6300 Series components including solenoid replacement kits for all standard voltages.

Mortise Locks and Cylindrical Locks

Operate the lever handle and confirm that the latch bolt retracts fully and returns smoothly. If the lever is loose at the rose or the latch requires multiple attempts to engage the strike, the lever return spring is likely fatigued.

Check the strike alignment. A strike that has shifted from door sag or frame movement produces inconsistent latch engagement and accelerates latch bolt wear. Re-aligning the strike before it causes bolt damage is a 15-minute task compared to the service call that comes after the bolt wears out.

Commercial mortise lock parts and cylindrical lock parts at Security Parts are organized by model number so that the correct lever return spring, spindle assembly, or strike can be confirmed against the installed hardware before ordering.

Deadbolts

Extend and retract the deadbolt manually to confirm smooth operation. A deadbolt that sticks in the extended position or requires excessive key force to retract typically indicates cylinder wear or a misaligned strike pocket.

On double-cylinder applications, test both sides independently. Check that the throw bolt extends fully to the rated 1-inch depth on Grade 1 models. Partial throw engagement reduces both the security and the resistance to forced entry that the Grade 1 rating was designed to provide. Replacement deadbolt parts including cylinders, strikes, and throw assemblies are available at Security Parts for Schlage B Series and compatible models.

The Quarterly Mechanical Inspection Checklist

Lubrication Schedule and Lubricant Selection

This is the most frequently mishandled maintenance task in commercial door hardware. Petroleum-based lubricants including WD-40 and similar aerosol products are not appropriate for lock cylinders or mechanical latch mechanisms. These products provide short-term lubrication but attract and hold dust and metal particles. Over weeks and months, the lubricant becomes a fine abrasive paste inside the mechanism. Key operation stiffens, spring performance degrades, and components that would otherwise last years wear out prematurely.

The correct lubricant for commercial lock cylinders and mechanical door hardware is a dry lubricant. Dry graphite powder or a dry PTFE (Teflon) spray provides lubrication without collecting debris. A properly maintained cylinder and latch mechanism under commercial use needs lubrication approximately every two to three years, not every quarter.

For door closer arms and track assemblies, a light machine oil or a synthetic grease applied at the pivot points is appropriate. The closer hydraulic system is sealed and is not lubricated externally.

Fastener and Torque Check

All mounting hardware for exit devices, door closers, and lock sets should be checked and tightened quarterly. Mounting screws on door closers and exit devices loosen gradually from the vibration of each door cycle. A closer arm mounting screw that has backed out half a turn is not visible to a casual inspection but creates enough play in the installation to accelerate wear on the arm casting and the closer body spindle connection.

Tighten to the manufacturer's specified torque where published. Do not over-torque, particularly in wood door applications where stripping the screw hole creates a more serious problem than a loose fastener. If a screw hole is stripped, replace with the appropriate repair plug before reinstalling the fastener.

Alignment and Door Geometry Check

A sagging door puts stress on every piece of hardware attached to it. The latch bolt works harder to engage a strike that is no longer in the correct position. The closer arm works harder because the door's center of gravity has shifted. The exit device latch bolt wears faster because the strike alignment has changed.

Door sag is visible at the top latch edge of the door: a sagging door widens the gap at the top of the latch edge and narrows at the bottom. The fix is hinge adjustment or hinge replacement. Catching door sag at the quarterly check prevents it from progressing to a point where the hardware damage is more expensive than the hinge work.

The Annual NFPA 80 Compliance Inspection

What the 13-Point Fire Door Assembly Inspection Covers

NFPA 80 Section 5.2.4 requires that every swinging fire door assembly be inspected using a comprehensive checklist that evaluates the door as a complete system. The 13 critical inspection points cover:

Fire door label present, legible, and not painted over
Door leaf condition, no holes, cracks, or broken components
Frame condition, securely anchored with no damage
Intumescent seals intact where required by the listing
Door clearances within NFPA 80 tolerances
Hinges correct in number and type, no broken or missing fasteners
Latching hardware actively engaging the strike plate
Door closer present and door closes fully from any open position
Door latches positively without manual assistance
Coordinator present if required on double-leaf doors, inactive leaf closes first
Glazing intact with no cracks, glazing beads and clips secure
No hold-open devices unless connected to the fire alarm system
No field modifications that void the UL listing

Door Clearance Tolerances Under NFPA 80

The maximum clearance at the bottom of a fire door is 3/4 inch (19mm) under NFPA 80. The maximum clearance at the head and jambs is 1/8 inch. For meeting edges on double door pairs, the maximum is 1/8 inch plus 1/16 inch. These tolerances are measured, not estimated visually.

Excessive bottom clearance is among the most commonly cited deficiencies. It allows smoke and flame to pass through the opening before the door's full fire resistance period has elapsed. The correction is typically a new door sweep or bottom seal replacement.

After-Maintenance Re-Inspection Requirement

Any fire door assembly that has had hardware replaced, glazing changed, or other listed-hardware work performed must be re-inspected after the work is complete. This is a requirement most facility maintenance teams are not aware of. It means that replacing a door closer on a fire door is not complete until the assembly has been re-checked against the inspection criteria.

Keeping Records That Protect the Building Owner

Inspection records must include the facility information, the inspector's credentials, the inspection date, each door's location and identification number, the results of every inspection point, and any deficiencies found along with corrective actions taken. These records must be signed and retained for a minimum of 3 years. Healthcare facilities may have additional documentation requirements under Joint Commission standards beyond the NFPA 80 baseline.

Records should be kept in a format that can be presented to an AHJ on request, whether paper or electronic. The critical requirement is that the record be traceable to a specific door, a specific inspector, and a specific date.

How to Identify When to Repair vs Replace a Component

The Repair-vs-Replace Decision for Exit Devices

A complete Von Duprin exit device costs significantly more than the component that actually failed. The center case, which contains the rack-and-pawl latch mechanism, is the most common failure point on heavy-traffic installations. Replacing just the center case restores full device function at a fraction of the cost of a new unit.

The same logic applies to dogging assemblies, latch bolts, and push bar end guides. These components wear independently of the rest of the device. Identifying which part failed, and having it in stock, is the difference between a 20-minute repair and a full device replacement.

The Repair-vs-Replace Decision for Door Closers

A door closer body that is leaking hydraulic fluid has exceeded its service life and requires full replacement. Hydraulic door closers are factory-sealed and cannot be refilled in the field. A body that is not leaking but producing inconsistent closing behavior can almost always be corrected by adjusting the sweep speed, latch speed, and backcheck valves.

Arm replacements are appropriate when the casting is cracked at a pivot point. A cracked arm that is not replaced will fail completely under the next significant door-opening force. The arm is a model-specific component on LCN closers: a 4040XP arm is different from a 3130 concealed closer arm, and neither crosses to the other series.

The Repair-vs-Replace Decision for Electric Strikes

A solenoid failure is the most common reason an electric strike stops responding to the access control signal. The solenoid kit on Von Duprin 6000 Series electric strikes (050240 for 24VDC, 050237 for 12VDC) fits every model in the series, and replacing only the solenoid restores full function. A strike body that is physically damaged or misaligned may require full replacement.

Why Choose Security Parts for Commercial Door Hardware Replacement Components

Security Parts has been serving the commercial door hardware industry for more than 30 years. The catalog covers Von Duprin, LCN, Schlage, and Falcon hardware with model-specific pages for every series we carry.

The interactive parts diagram on every model page is what separates Security Parts from general hardware distributors. You can navigate to the exact device model installed in the building, see the full assembly in a diagram, click on the component that failed, and confirm the correct part number before the order is placed. That one step prevents the majority of wrong-part orders.

Our warehouses are distributed across the United States. Common components ship same-day. Expedited options are available when a door-down situation needs a fast turnaround. Compatibility questions are handled by trained hardware specialists at 845-935-0301 and by live chat before the order ships, not after.

For ongoing maintenance programs, the commercial exit devices catalog, the commercial door closers parts, and the complete Von Duprin, LCN, Schlage, and Falcon inventories are organized to make parts identification fast and accurate for every device in the building.

Conclusion

Commercial door hardware maintenance is one of the most overlooked responsibilities in facility management, and one of the most consequential. A door closer that drifts open, a panic bar that will not latch, or an electric strike that stops responding costs far less to fix before it fails than after. The NFPA 80 annual inspection is a legal requirement, not an optional safety measure, and the documentation it generates protects building owners when a fire marshal, insurer, or CMS surveyor reviews compliance.

The monthly visual checklist takes minutes. The quarterly mechanical checks take an hour across a typical floor. The annual inspection is the formal compliance layer that requires a qualified person and signed documentation. Together, these three tiers keep hardware performing to its rated specifications, keep the building out of compliance violations, and keep replacement costs controlled by catching component failures before they become full device replacements.

Security Parts carries the replacement components for every hardware category in this guide. With more than 30 years in commercial door hardware, model-specific parts pages with interactive diagrams, same-day shipping from US warehouses, and pre-order compatibility support at 845-935-0301, we make accurate parts sourcing as straightforward as the maintenance schedule itself.

Frequently Asked Questions

How often does commercial door hardware need to be inspected?

Monthly visual checks, quarterly mechanical checks for lubrication and fasteners, and annual NFPA 80 inspections for every fire-rated door assembly. Non-fire-rated hardware should follow monthly and quarterly schedules but does not carry the mandatory annual inspection requirement.

What does "annually" mean under NFPA 80?

NFPA 80 defines the annual inspection window as a minimum of 9 months and a maximum of 15 months between inspections. This is not a suggestion that inspections can be skipped in any given year. It is a scheduling tolerance to accommodate facility logistics. Going beyond 15 months without a documented inspection is a code violation.

What lubricant should be used on commercial door hardware?

Dry graphite powder or dry PTFE spray for lock cylinders, latch mechanisms, and dogging assemblies. Light machine oil or synthetic grease at closer arm pivot points. Never use petroleum-based aerosol lubricants on lock cylinders. They attract debris, form an abrasive paste, and accelerate component wear rather than preventing it.

What are the maximum clearance tolerances for fire doors under NFPA 80?

Maximum 3/4 inch at the bottom of the door, maximum 1/8 inch at the head and side jambs, and maximum 1/8 inch plus 1/16 inch at meeting edges for double door pairs. These are measured tolerances, not visual estimates. Exceeding them is a deficiency that must be corrected before the inspection record can be signed off.

Is re-inspection required after replacing door hardware on a fire door?

Yes. NFPA 80 requires that any fire door assembly that has had hardware replaced or modified be re-inspected after the work is complete. This applies to door closer replacement, exit device replacement, and any other listed hardware change. The re-inspection confirms that the assembly still meets its rated requirements after the work.

What is the ADA requirement for door opening force on commercial doors?

The Americans with Disabilities Act requires a maximum opening force of 5 pounds for interior doors on accessible egress routes. The door must also take a minimum of 5 seconds to travel from 90 degrees open to 12 degrees open. Both requirements apply to the door as a system, meaning closer adjustment that reduces force may need to compensate for speed as well.

How long must NFPA 80 inspection records be kept?

A minimum of 3 years. Records must be signed by the inspector and available for review by the authority having jurisdiction. Healthcare facilities may have additional documentation requirements under CMS and Joint Commission standards beyond the NFPA 80 minimum retention period.

What triggers an immediate hazard classification under NFPA 80?

NFPA 80 Section 5.2.3.3 classifies any condition that prevents a fire door from closing or latching automatically as an immediate hazard. This includes a missing latch bolt, broken hinges preventing door movement, and obstructions that cannot be removed during the inspection. Immediate hazards require correction before the inspection record is completed or within a 24-hour window as directed by the AHJ.

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LCN 4000 Series Surface Mounted and 2210 High-Security Concealed Door Closer Parts: Complete Guide Thursday, July 9, 2026

Security Parts carries parts for the full LCN 4000 Series surface-mounted closers: 4010 (pull side regular arm), 4020 (top jamb), 4030 (universal moderate traffic), 4040/4040XP (heavy institutional), 4050A (cast aluminum heavy duty), 4110 (parallel arm with EDA), and 4000T (pocket door). Also covered: the 2210 Series high-security overhead concealed closer for correctional and vandal-prone environments. The 4010, 4020, and 4110 are application-specific: mounting and handing must be specified at order time. The 4040XP and 4050A are non-handed. All big-body 4000 Series use the Fast Power Adjust indicator system. The 4010/4020/4110 use a flat-sided oval spindle; the 4040/4040XP use a six-sided hex spindle. Arms are not cross-compatible between these spindle types.

The LCN 4000 Series is the heaviest-duty surface-mounted closer line in the LCN catalog. Where the 1000 Series (1260 and 1460) serves light-to-medium commercial applications, the 4000 Series covers everything from moderate-traffic institutional interiors through the most demanding high-abuse applications in government, healthcare, and correctional environments. Each model in the series is engineered for a specific mounting position, and this specificity is the most important part of understanding how to order correct replacement parts.

Browse the complete LCN parts catalog at Security Parts. For the full LCN door closer and automatic operator catalog, browse the commercial door closer parts catalog.

30-year Warranty on LCN 4040XP Series, LCN's most durable surface closer

25-year Warranty on LCN 4050A cast aluminum Series

3 spindle types Hex (4040XP), oval (4010/4020/4110), star (1260/1460): arms not cross-compatible

TORX Tamper-resistant fasteners on LCN 2210 high-security concealed closer

Application-Specific vs Universal: The Core 4000 Series Decision

The LCN 4000 Series divides into two categories that determine the ordering process. Application-specific closers require the installer to specify mounting position and door handing at order time. Universal closers can be installed in any mounting configuration after they arrive in the field.

Application-specific 4000 Series: The 4010, 4020, and 4110 are each engineered for one mounting position and one only. The 4010 for regular arm pull side, the 4020 for top jamb, the 4110 for parallel arm push side. Ordering a 4010 and trying to mount it top jamb produces a door that cannot close correctly because the arm geometry and cylinder orientation are specific to the pull-side mounting template.

Universal 4000 Series: The 4040XP, 4050A, and 4030 are universal or near-universal, meaning they support multiple mounting configurations from the same unit. The 4040XP and 4050A can be installed hinge pull side, top jamb push side, and parallel arm push side from the same closer. The 4041P (4040XP equivalent) and 4031P are the fully universal options within the 4000 family.

The ordering error that generates the most 4000 Series returns: Ordering a 4010 or 4110 when a universal closer was needed, or ordering the wrong hand on an application-specific model. Every 4010, 4020, and 4110 must be ordered with the correct handing specified (right hand or left hand) because the cylinder orientation and arm geometry are set at the factory. A 4010 right-hand closer installed on a left-hand door produces a device that works mechanically but closes the door incorrectly or requires the arm to be forced into a non-design position. Confirm the door handing from the hinge side before ordering any application-specific 4000 Series closer.

LCN 4000 Series: Every Model Explained

LCN 4010 Series

Pull Side | Regular Arm | Application-Specific | Handed

Specifically designed for regular arm (hinge pull side) installations only. Heavy-duty big-body closer. Fast Power Adjust indicator. Flat-sided oval spindle. 4010-72 plastic or 4010-72MC metal cover. Interior and exterior doors in offices, schools, government buildings. Must specify handing at order time.

LCN 4020 Series

Top Jamb | Application-Specific | Handed

Specifically designed for top jamb applications where the closer mounts on the head frame above the door. Common on glass storefronts, hospitals, and environments requiring frame-mounted hardware. 1-1/2 inch clearance behind door for 90 or 180 degree installation. Head frame less than 3-7/8 inches requires plate 4020T-18. Flat-sided oval spindle. Must specify handing.

LCN 4030 Series

Universal | Moderate Traffic | 30-Year Warranty

Universal closer for moderate traffic conditions supporting hinge pull side, top jamb push side, and parallel arm push side mountings. Non-sized adjustable 1 to 4, interior doors to 4 feet, exterior to 3 feet. Metal cover standard. Forged steel main arm. 30-year limited warranty. Grade 1.

LCN 4040 / 4040XP Series

Universal | Heavy Institutional | Non-Handed | 30-Year

LCN's most durable heavy-duty surface closer. Cast iron body, 1-1/2 inch piston, double heat-treated pinion, all-weather Liquid X fluid. Six-sided hex spindle. Green Dial spring adjustment 1 to 6. Non-handed. Pull side, top jamb, parallel arm capable. 4040XP is the current generation; the 4040 was the predecessor. Buy American Act compliant. 30-year warranty.

LCN 4050A Series

Universal | Cast Aluminum | Non-Handed | 25-Year

Cast aluminum body (lighter than cast iron) with full-complement bearing, 1-1/2 inch piston, 11/16 inch double heat-treated pinion. Green Dial 1 to 6 spring adjustment, ships set to size 3. 2-3/8 inch by 6-3/4 inch mounting hole pattern (most common commercial footprint). Non-handed. Pull side, top jamb, parallel arm. 25-year limited warranty. Liquid X all-weather fluid eliminates seasonal adjustment.

LCN 4110 Series

Parallel Arm Push Side | EDA Standard | Application-Specific

Purpose-built for parallel arm push side installations. Ships with Extra Duty Arm (EDA) as standard. Ideal for classroom doors, auditorium doors, healthcare environments where closer must be on push side and aesthetics or security require parallel arm concealment. Flat-sided oval spindle. Must specify handing. Fast Power Adjust. 4110-72 cover part number.

LCN 4000T: Pocket Door Closer

The LCN 4000T is the specialty member of the 4000 Series family, designed specifically for pocket doors that slide into a wall cavity rather than swinging on hinges. It is the only LCN surface-mounted closer in the 4000 Series built for this application. Arms, cylinders, and cover parts from other 4000 Series closers are not compatible with the 4000T because the mechanical interface for a sliding door is fundamentally different from a swinging door configuration.

The Spindle Geometry Problem: Why Arms Fail to Fit Across 4000 Series Models

The most expensive and most avoidable parts ordering mistake in the entire LCN 4000 Series catalog happens because of the spindle geometry difference that is never documented in buyer-facing parts content. Three distinct spindle shapes exist in the LCN lineup, and arms are machined specifically to one spindle shape.

Series	Spindle Shape	Arms That Fit	Cross-Compatible With
4040 / 4040XP	Six-sided hex	4040XP-specific arm family	Not compatible with 4010, 4020, 4110, or 1000 Series
4010 / 4020 / 4110	Flat-sided oval	3077 regular arm, 4010/4020/4110 arm family	Compatible with each other and with 4040 (non-XP); NOT with 4040XP or 1000 Series
1260 / 1460 (1000 Series)	Eight-sided star	1260/1460 arm family	Not compatible with any 4000 Series model

The practical consequence of this table: a technician who replaces a 4040XP on a door with a 4010 cannot use the existing 4040XP arm. The 4040XP hex spindle arm will not engage the 4010 oval spindle. The technician must order a new arm for the 4010. And conversely, if a 4010 is replaced with a 4040XP, the 4010 oval spindle arm cannot be reused on the XP's hex spindle. A new XP-specific arm is required.

The arm that fits correctly but creates a safety problem: A 4040 (non-XP, older generation) arm fits the 4040XP hex spindle because they share the same spindle shape. However, the 4040XP was redesigned with updated arm geometry that provides better backcheck cushioning and improved opening control. Installing a 4040 (non-XP) arm on a 4040XP cylinder produces a closer that functions but does not provide the full backcheck protection that the XP arm delivers. On high-abuse institutional doors where backcheck prevents door slams, the undersized backcheck cushion from a non-XP arm on an XP cylinder results in repeated hard door stops that damage the door, frame, and hinge system. Always order XP-specific arm parts for any 4040XP installation.

LCN 4000 Series Parts Reference

Cylinder Assemblies

Every 4000 Series closer cylinder assembly part number follows the series naming convention. The 4010 Series cylinder is 4011-3071 (with the 6 suffix for size 6: 4011(6)-3071). The 4010 also supports a delayed-action version (4011-3071DEL) and a TEL (time-elapsed latch) version (4011(6)-3071TEL).

Key cylinder assembly variants available across the 4000 Series include standard, delayed action (DEL), temperature-equalized latch (TEL), and fire-rated versions. When ordering any cylinder assembly replacement, always confirm whether the existing installation uses a standard or specialty variant before placing the order. A standard cylinder replacement on a door that had delayed-action will produce a door that latches immediately rather than after the delay the occupants expect.

Cover Part Numbers: The -72 Convention

LCN door closer cover part numbers follow the convention of series number followed by -72 for the standard plastic cover. The 4010 plastic cover is 4010-72. The 4010 metal cover is 4010-72MC. The 4020 metal cover is 4020-742 (note the slightly different numbering on the 4020 metal cover). The 4040 cover is 4040-72. The 4110 cover is 4110-72. This convention allows field technicians to identify the correct cover replacement without a catalog lookup if they know only the closer series number.

Regular Arm 3077: Which Series It Fits

The LCN regular arm 3077 is the standard arm shipped with most LCN surface-mounted closers. It works with the 1260, 1460, 4010, 4020, and 4040 (non-XP). It does not work with the 4040XP (different spindle shape), the 4110 (ships with EDA as standard and requires different arm geometry for parallel arm mounting), or any overhead concealed series. The 3077 is ordered with the series prefix: 4010-3077 for the 4010, 4020-3077 for the 4020, 4040-3077 for the 4040 (non-XP).

Fast Power Adjust: The Spring Adjustment That Prevents Cylinder Replacement

The 4010, 4020, 4030, and 4110 Series all include the Fast Power Adjust indicator system for spring power adjustment. This allows the spring power setting to be increased or decreased in the field without removing the cover or replacing the cylinder. When a 4010 or 4110 closer begins closing a door slowly or not latching reliably, the Fast Power Adjust should be the first intervention before any cylinder replacement is considered.

Most unnecessary cylinder replacements on 4010, 4020, and 4110 closers happen because the technician is not aware that the spring power is adjustable on these models. A closer with a spring power setting at size 1 on a heavy exterior door will not close reliably. Increasing the spring power to size 3 or 4 (appropriate for the door weight) restores reliable closing without any parts replacement. This takes two minutes with the correct allen key. A cylinder replacement for the same symptom takes 30 minutes and costs the cylinder assembly price.

LCN 4040XP: The Institutional Benchmark and Its Unique Features

The LCN 4040XP is identified in LCN's own catalog as the most durable and flexible heavy-duty closer designed for institutional and other demanding high-traffic applications. It is the reference product against which all other surface-mounted closer specifications are compared for institutional procurement.

What Makes the 4040XP Different from Other 4000 Series Models

The 4040XP's distinguishing features at the parts level are the cast iron body construction (versus the cast aluminum of the 4050A), the 1-1/2-inch piston diameter, the double heat-treated pinion journal, the six-sided hex spindle, the non-handed universal installation, and the all-weather Liquid X fluid that eliminates seasonal closing speed adjustment. The six-sided hex spindle on the XP accepts higher torque loads than the oval spindle on the 4010, 4020, and 4110, making it more resistant to spindle wear under the repeated high-cycle stress of institutional applications.

4040XP Arm Requirements: The Minimum Head Frame Clearance

The 4040XP requires a minimum top rail of 3-3/4 inches for standard installations. If the top rail is less than 3-3/4 inches, the plate 4040XP-18 is required. This plate is also required for parallel arm mounting where reveal is less than the specified minimum. The 4040XP auxiliary stop is recommended at the hold-open point or where the door cannot swing beyond 120 degrees. On doors mounted to pivot rather than butt hinges, the hinge width should not exceed 5 inches for correct XP arm function.

The 4040XP fifth hole spacer that most technicians don't know about: The parallel arm shoe installation on the 4040XP requires a fifth hole spacer (part 4040XP-201) to support the parallel arm shoe. This part is included with parallel arm 4040XP (P4040XP) orders but is not always stocked by general hardware distributors. When a 4040XP is installed in parallel arm configuration and the shoe is unstable or the arm produces unusual closing behavior, the fifth hole spacer is frequently missing. Confirm the 4040XP-201 is present before diagnosing any other parallel arm closer issue on the XP.

LCN 4050A: The Cast Aluminum Alternative and Its Specification Sweet Spot

The LCN 4050A serves the specification space between the 1000 Series light-to-medium duty closers and the 4040XP institutional standard. It is the correct specification for commercial building applications that require heavy-duty performance with a competitive price, but where the full institutional specification of the 4040XP is not required in the project scope.

4050A Construction vs 4040XP Construction

The 4050A uses cast aluminum for the outer cylinder body rather than the cast iron used in the 4040XP. Cast aluminum is lighter and less expensive than cast iron while providing adequate structural integrity for commercial (non-institutional) applications. The internal components of the 4050A match the 4040XP in piston diameter (1-1/2 inches) and pinion treatment (double heat-treated). The Liquid X all-weather fluid is also shared between the two series, eliminating seasonal adjustment on both.

The 4050A's standard mounting hole pattern (2-3/8 inches by 6-3/4 inches) is described by LCN as the most common commercial footprint, which means the 4050A can retrofit onto most commercial doors that previously had a 4000 Series or competitor closer without requiring new holes. This is one of the 4050A's underappreciated specification advantages for renovation work.

LCN 2210 Series: High-Security Overhead Concealed Closer for Correctional Environments

The LCN 2210 Series is the overhead concealed counterpart to the 4210/4510 Smoothee surface-mounted high-security closer. Where the Smoothee is visible on the door face but tamper-resistant, the 2210 provides complete concealment: the cylinder mounts in the head frame, and the arm and track mount in the top rail of the door. Nothing is visible from the door face in the closed position.

Why Complete Concealment Matters in Correctional Environments

In correctional facilities, psychiatric units, and juvenile detention environments, any hardware visible on the door face presents a potential leverage point. Surface-mounted door closers, regardless of their tamper resistance, provide a grasping surface and a mechanical anchor that motivated occupants can attack with improvised tools. The 2210's complete concealment eliminates this exposed hardware entirely. From the occupant's side of a door with a 2210 installed, the door appears to have no closer hardware at all.

2210 Series Key Specifications

The 2210 uses TORX tamper-resistant fasteners rather than standard Phillips or hex-head screws. Standard fastener tools carried by most people cannot drive TORX fasteners, creating a meaningful access barrier for impromptu disassembly attempts. The arm is forged steel with a heavy steel mounting plate engineered for high-abuse application loads. The single-lever arm and security track (non hold-open standard) are included with standard shipments.

The 2210 includes an optional door position switch (DPS) that signals a security or building automation system when the door is open or closed. This integrates the 2210 with correctional facility monitoring systems, providing real-time door status for every monitored opening. Standard cylinders are sized for interior doors to 4 feet 6 inches and exterior doors to 3 feet 6 inches. Handing must be specified (right or left swinging door) because the cylinder mounts in the head frame with a fixed orientation.

SRI Finish Option for Corrosive Environments

The 2210 is available with the LCN Special Rust Inhibiting (SRI) process for installations where the environment is potentially corrosive: laundry rooms in correctional facilities, coastal building locations, chemical storage areas, or any application where moisture and cleaning chemicals create above-normal corrosion risk. LCN's SRI process treats ferrous metal components with an inhibiting pretreatment before the powder coat is applied. The resulting finish exceeds the 100-hour salt spray protection level of standard LCN powder-coated finishes. This is not a standard option across the full LCN catalog and is specific to the high-security closer line.

The DPS option that most correctional facility specifications miss: The LCN 2210 Series optional door position switch (DPS) converts a mechanical closer into a door status monitoring device at essentially zero additional hardware cost over the baseline closer. In correctional environments where door status monitoring is a security requirement at every controlled opening, specifying the 2210 with DPS eliminates the need for a separate door status sensor on every closer-equipped door. Many correctional facility specifications that are already requiring the 2210 for tamper resistance overlook the DPS option because the specification writers are familiar with the closer product but not with the integrated monitoring capability. The DPS adds real-time door open/closed status to the security system at the point of the closer, not as a separate sensor installed later.

Comparing the Full 4000 Series: Choosing the Right Model

Model	Body	Mounting	Handing	Spindle	Spring Range	Warranty
4010	Cast iron	Pull side only	Handed	Flat oval	Non-sized adjustable	LCN standard
4020	Cast iron	Top jamb only	Handed	Flat oval	Non-sized adjustable	LCN standard
4030	Cast iron	Universal 3-way	Non-handed	Flat oval	1 to 4	30-year
4040 / 4040XP	Cast iron	Universal 3-way	Non-handed	Hex (6-sided)	1 to 6 (Green Dial)	30-year
4050A	Cast aluminum	Universal 3-way	Non-handed	Flat oval	1 to 6 (Green Dial)	25-year
4110	Cast iron	Parallel arm only	Handed	Flat oval	Non-sized adjustable	LCN standard
4000T	Cast iron	Pocket door	N/A	Unique	Sized	LCN standard
2210	Cast iron concealed	Frame/door overhead	Handed	Track system	Sized 1 to 4	15-year

What Fails First on LCN 4000 Series and 2210 Closers

Application-Specific 4000 Series (4010, 4020, 4110)

Spring power drift: Over years of high-cycle use, the spring power setting on the Fast Power Adjust system can drift downward, particularly on heavy exterior doors. The door begins closing more slowly and eventually fails to latch. Before diagnosing this as hydraulic fluid loss or cylinder failure, check and increase the Fast Power Adjust setting to confirm the spring power is at the correct level for the door weight.

Arm screw loosening: The 159 arm screw (1/4-20, 3/4-inch head diameter) holds the arm on the spindle across all 4000 Series models. High-cycle applications produce vibration that works the arm screw loose over time. A loose arm screw presents as a door that closes slowly or drifts open because the arm is spinning on the spindle instead of transmitting spring force to the door.

Fluid leak: A closer that closes too fast despite valve adjustment at the maximum restriction setting has lost hydraulic fluid. Fluid loss produces a loss of regulated closing control. Cylinder replacement is the correct service action. Additional valve adjustment on a dry cylinder produces no improvement.

4040XP

Parallel arm shoe wear: On parallel arm 4040XP installations, the shoe that connects the arm to the parallel bracket takes repeated mechanical load. The shoe connection can wear or the fasteners can loosen, producing a bouncy or unstable closing arc. Confirm the 4040XP-201 fifth hole spacer is present and the shoe fasteners are torqued correctly before diagnosing any other parallel arm complaint.

2210 Series

Track roller wear: The 2210 uses a track system (similar in concept to the 3130) where a roller travels in the track on every door cycle. Track roller wear is the primary maintenance item on the 2210. A 2210 installation that begins producing closing resistance or does not fully close despite correct spring sizing usually has a worn or seized track roller. Replacing the track roller restores correct operation without cylinder replacement.

Browse the LCN parts catalog at SecurityParts.com for all 4000 Series and 2210 components with interactive diagrams. For the full LCN door closer catalog including Sentronic, 1000 Series, and overhead concealed series, browse the commercial door closer parts catalog. For related exit device and electric strike parts on the same doors, browse exit device parts and electric strike parts. Pre-order support is at 845-935-0301 or the contact page.

Why Choose Security Parts for LCN 4000 Series and 2210 Parts

Spindle geometry table, Fast Power Adjust diagnostic, 4040XP fifth hole spacer, 2210 DPS monitoring option, and same-day shipping on stocked parts.

Spindle Geometry Table

We document that the 4040XP uses a hex spindle, the 4010/4020/4110 use an oval spindle, and 1000 Series uses a star spindle. Arms are not cross-compatible. This table prevents the most common wrong-arm order in the 4000 Series.

Fast Power Adjust First

We document the Fast Power Adjust spring system on the 4010, 4020, and 4110 as the first-check item before any cylinder replacement. Many unnecessary cylinder replacements happen because the installer did not know spring power was adjustable.

2210 DPS Option

We document the 2210's optional door position switch as a integrated security monitoring feature that most correctional specs overlook. Adding DPS at spec time eliminates a separate sensor installation cost.

Same-Day Shipping

Most 4000 Series and 2210 parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for spindle identification and arm compatibility support.

What Makes SecurityParts.com Different for LCN 4000 Series Parts

We document the three-spindle-type architecture of the LCN closer catalog (hex for 4040XP, oval for 4010/4020/4110, star for 1000 Series) and explain why arms cannot be cross-used between spindle types. No other parts supplier documents this relationship at the buying stage.
We document the 4040 non-XP arm on a 4040XP as a functional but deficient combination: it works mechanically but provides inadequate backcheck protection on high-abuse institutional doors. Correctly using XP-specific arms prevents hardware damage from repeated hard door stops.
We document the 4040XP fifth hole spacer (4040XP-201) as a parallel arm installation component that is frequently missing when a parallel arm shoe is unstable. Missing this part generates closure behavior complaints that are misdiagnosed as arm or cylinder failures.
We document the 2210 Series optional DPS as a door monitoring integration feature that correctional facility specifications frequently overlook, eliminating a separate sensor installation on every monitored opening in the facility.
We carry LCN 4000 Series parts alongside Von Duprin and Falcon exit device parts, electric strike parts, exit alarm parts, and Schlage mortise lock parts for complete door hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

LCN 4000 Series closers appear on every commercial egress and fire-rated door alongside exit devices, electric strikes, and deadbolts. The 2210 appears on correctional facility doors alongside high-security cylindrical and mortise lock hardware.

For Von Duprin and Falcon exit device parts on egress doors with LCN 4040XP or 4050A closers, browse the exit devices catalog. For Von Duprin electric strike parts on access-controlled doors in the same building, browse the electric strikes catalogue. For Von Duprin Guard-X and Detex exit alarm parts on secondary exits, browse the exit alarms catalog. For Schlage ND and ALX Series cylindrical lock parts on secured interior doors, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on high-security entries in the same facility, browse the mortise locks catalog.

Browse the complete all products and parts catalog to source LCN, Von Duprin, Schlage, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About LCN 4000 Series and 2210 Closer Parts

What is the difference between the LCN 4010, 4020, and 4110 door closers?

All three are heavy-duty application-specific 4000 Series closers requiring mounting and handing specification at order time. The 4010 is designed exclusively for regular arm pull side (hinge side) installations. The 4020 is designed exclusively for top jamb applications where the closer mounts on the frame head above the door. The 4110 is designed exclusively for parallel arm push side installations and ships with an Extra Duty Arm as standard. None converts to a different mounting without a different arm configuration.

What is the LCN 4050A Series and how does it differ from the 4040XP?

Both are non-handed universal heavy-duty surface closers with adjustable spring sizes 1 to 6 and the Green Dial system. The 4040XP uses a cast iron body and is LCN's most durable institutional specification closer with a 30-year warranty. The 4050A uses cast aluminum, is lighter, carries a 25-year warranty, and has the most common commercial mounting footprint (2-3/8 inch by 6-3/4 inch) making it ideal for retrofit applications. Both use Liquid X all-weather fluid eliminating seasonal adjustment.

What is the LCN spindle difference between 4000 Series models and why does it matter for arms?

The 4040 and 4040XP use a six-sided hex spindle. The 4010, 4020, and 4110 use a flat-sided oval spindle. The 1260 and 1460 use an eight-sided star spindle. Arms are machined to one specific spindle type and are not interchangeable across spindle types. A 4040XP arm will not fit a 4010 closer. Always confirm the series and spindle type before ordering any replacement arm.

What is the LCN 4000T pocket door closer?

The 4000T is the only LCN 4000 Series model designed for pocket doors that slide into a wall cavity. All other 4000 Series closers are for swinging doors. The 4000T's arm, cylinder, and track are specific to sliding door applications and are not interchangeable with any other 4000 Series components. It is the correct specification for pocket door applications where controlled automatic return-to-closed is required.

What is the LCN 2210 Series and when is it specified instead of the 4210/4510 Smoothee?

The 2210 is a heavy-duty high-security overhead concealed closer with complete concealment (cylinder in head frame, arm and track in door top rail) and TORX tamper-resistant fasteners. The 4210/4510 Smoothee are surface-mounted high-security closers. The 2210 is specified instead of the Smoothee when complete concealment is required to eliminate any visible surface hardware. This applies in correctional facilities, psychiatric units, and vandal-prone environments where any surface-mounted hardware presents an attack or leverage opportunity.

What is the Fast Power Adjust indicator on LCN 4000 Series closers?

The Fast Power Adjust indicator is the spring power adjustment reference on the 4010, 4020, 4030, and 4110 Series closers that allows spring power to be changed in the field without removing the cover or replacing the cylinder. When a 4010 or 4110 begins closing too slowly or fails to latch, increasing the spring power with the Fast Power Adjust is the first diagnostic step before any component replacement. Many unnecessary cylinder replacements occur because the technician was unaware that spring power was adjustable on these models.

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Schlage Padlocks, Hasps, Cable Locks and Installation Tools: Complete Commercial Guide Wednesday, July 8, 2026

Security Parts carries Schlage padlocks including the 850410 covered laminate padlock, 855156 shackle-less padlock, 855101 Kryptonite vehicle hasp, 855118 high-security double hinge hasp, and 994800/994862 cable locks, plus Schlage installation tools including the 24002693 lever removal tool (ND and L Series), 021415 spanner wrench (D and L Series), 40-015 boring bit, 39-029 finish selector kit, and 40-029/40-030 strike marking chisels. Schlage padlocks use full-size Schlage cylinders that integrate directly into any Schlage masterkey system, allowing the building master key to open padlocks alongside all door hardware.

Schlage padlocks and portable security hardware solve the key management problem that undermines most commercial facility security programs: when a building uses Schlage door hardware on a masterkey system but standard padlocks on storage rooms, equipment cages, and utility closures, facilities staff carry two separate key sets. Schlage padlocks eliminate this by using the same full-size Schlage cylinder format that integrates into any building's existing Schlage key schedule. One key. All locks. Every door and every padlock.

The installation tools in the Schlage accessories catalog serve a different purpose: they are the precision instruments that determine whether field lock installation produces a door that operates correctly the first time or generates a callback. Strike misalignment, lever damage from improper removal, and bore errors are the three most common field-correctable installation failures, and the Schlage tool catalog addresses all three directly.

Browse the complete Schlage padlocks catalog and cylinders, keys and installation accessories catalog at Security Parts. For the full Schlage commercial hardware range, browse the Schlage commercial hardware catalog.

100+ years Schlage padlock history; full-size cylinders since the beginning

Lifetime Schlage padlock warranty on all models when correctly maintained

Aug 2012 Date Schlage introduced the updated ergonomic 24002693 lever removal tool

Full-size Schlage cylinder format in every padlock: masterkey-compatible with all door hardware

Schlage Padlocks: Why Full-Size Cylinders Matter

Most commercial padlocks use proprietary pin tumbler cylinders that are smaller than the cylinders used in commercial door hardware. This size difference is why standard padlocks cannot be incorporated into a building's Schlage masterkey system. The cylinder format must match between padlocks and door hardware for masterkey integration to work.

Schlage padlocks use the same full-size Schlage cylinder format used in the ND Series cylindrical locks, the L Series mortise locks, the B Series deadbolts, and the CL Series cabinet locks. Because the cylinder format is identical, Schlage padlocks can be: keyed to match any change key in the building's key schedule (one padlock key, one door key), keyed alike with other padlocks to use a single padlock key, masterkeyed so the building's master key opens both doors and padlocks, and grand masterkeyed within multi-building campus systems.

The masterkey integration fact that eliminates the second key ring: A facilities manager in a commercial building who carries a Schlage master key for all doors typically also carries a separate key ring for padlocks on equipment cages, storage closets, mechanical rooms, and exterior gates. If those padlocks were specified as Schlage padlocks at the time of the building's key system design, the facilities master key would open every padlock as well as every door. This single-key operation is achievable at no additional cost by specifying Schlage padlocks when the padlocks are procured within the same master key schedule as the door hardware. Converting existing non-Schlage padlocks to Schlage during a rekeying event also achieves this. The key management benefit is the difference between a one-key building and a two-ring facility manager.

Schlage Padlock Product Guide

850410 Covered Laminate Steel Padlock

Standard Shackle | Weather Protected

Laminated steel body: multiple steel layers laminated together, providing better cut resistance than a single-body padlock of equal size. 1/4-inch diameter hardened steel shackle, 1-1/8-inch clearance. Rubber weather cover over cylinder for outdoor and all-weather use. 1-1/2-inch width. Available keyed different, keyed alike, or keyed to a building key schedule. Full-size Schlage cylinder for masterkey integration. Lifetime warranty.

855156 Shackle-Less Padlock (Kryptonite)

Recessed Bolt | Maximum Physical Attack Resistance

2-7/8-inch diameter round solid hardened steel body. No external shackle: locking bolt is completely internal, protected by the full-diameter steel body. Nickel chrome finish. Six-pin brass cylinder for pick and drill resistance. Bolt resists prying, cutting, and sawing attacks. Two keys supplied. For use with hasp or lock box where recessed padlock mounting is possible. Full-size Schlage cylinder.

855101 Kryptonite Vehicle Hasp

Vehicle Security | Specialized Application

Specialized hasp designed for vehicle cargo door security. Provides a padlock closure point on delivery trucks, cargo vans, and fleet vehicles where a standard door handle or built-in lock does not provide adequate security. Pairs with any Schlage shackle padlock. For fleet security operations requiring key system integration with building padlocks.

855118 High-Security Double Hinge Hasp

7-3/4 x 1-3/4 Inch | Double Hinge Design

Double hinge hasp for commercial secured enclosures. 7-3/4 inch by 1-3/4 inch. Two separate mounting pivot points prevent single-point prying, the primary attack vector on standard single-hinge hasps. For equipment storage doors, utility closures, and gate applications where the padlock is the primary security mechanism. Best paired with the 855156 shackle-less padlock.

994800 Cable Lock, 48 Inch

Flexible Steel Cable | Laminated Padlock

Flexible steel cable, 48 inches, with attached laminated padlock. For bicycle security, equipment anchoring, and portable asset protection where a fixed padlock and hasp are not practical. Full-size Schlage cylinder on the attached padlock allows masterkey integration for fleet or campus equipment management.

994862 Cable Lock, 180 Inch

Flexible Steel Cable | Laminated Padlock | Extended Length

Same construction as the 994800 but 180 inches (15 feet) in length. For large equipment, multiple asset anchoring, and applications where the anchor point is not adjacent to the secured object. The extended length accommodates posts, columns, and structural members at a distance from the secured asset.

Shackle-Less Padlock + Double Hinge Hasp: The Highest Commercial Combination

Most commercial security consultants specify padlock security based on padlock grade alone, without considering the hasp as part of the attack surface. A Grade 1 padlock on a cheap single-hinge hasp can be defeated by prying the hasp open, bypassing the padlock entirely without cutting the shackle. The padlock is irrelevant if the hasp fails first.

The highest-security portable lock configuration available in the Schlage catalog at SecurityParts.com pairs the 855118 double hinge hasp with the 855156 shackle-less padlock. The hasp's double hinge eliminates the single-point prying attack. The shackle-less padlock eliminates the shackle cutting attack. When the 855156 bolt is engaged through the hasp staple, the only remaining attack surface is the hasp mounting screws (addressed by proper mounting into structural material with appropriate fasteners) and the padlock body itself (hardened steel resisting cutting and drilling).

The hasp mounting detail that determines whether the padlock matters: A double hinge hasp mounted with standard wood screws into a door face provides significantly less resistance than the same hasp mounted with through-bolts into the door edge or frame, or with 3-inch screws into structural backing. The hasp-mounting fastener is the weakest link in most padlock security installations, not the padlock itself. When specifying any hasp installation, require through-bolting or structural-backed screws rather than surface-only fastening. This is the same logic as the LCN 4040SEH being worthless without an opposite-side closer: the system is only as strong as its weakest required component.

Schlage Installation Tools and Accessories

Schlage installation tools exist because field installation of commercial door hardware is a precision operation. The difference between a correctly installed Schlage lock that operates smoothly for years and a callback-generating installation is frequently one measurement error on a strike location or one damaged lever from improper removal. The Schlage tool catalog at SecurityParts.com covers the tools that prevent these errors.

24002693: Lever Removal Tool for ND and L Series

The 24002693 lever removal tool is the correct instrument for removing levers from Schlage ND Series cylindrical locks and L Series mortise locks. The tool provides the correct geometry to release the lever retention tab without damage to the lever, rose, or chassis housing.

Schlage introduced an updated, more ergonomic version of this tool on August 15, 2012, alongside Phase 1 of the ND Series improvement project. The new tool (24002693) includes a bottle opener as an additional ergonomic feature and is the current production version. It works on all ND Series and L Series locks regardless of manufacture date.

The improvised lever removal that generates the most common ND Series chassis damage: Field technicians who do not have the 24002693 tool frequently attempt lever removal using a flathead screwdriver to release the retention tab. The screwdriver geometry does not match the tab geometry and frequently breaks the retention tab clip or deforms the chassis opening. A broken retention tab on an ND Series chassis requires chassis replacement, which is a significantly more expensive repair than the 24002693 tool. Any facility or service company that regularly installs or services Schlage ND or L Series hardware should have the 24002693 in their standard service kit. The 24341471 pack of 20 tools is the economical option for companies with multiple service technicians.

021415: Spanner Wrench for D Series and L Series

The 021415 spanner wrench engages the spanner nut on Schlage D Series knobs and L Series mortise locks. The spanner nut is a cylindrical collar with notches cut around its perimeter, designed specifically to receive a spanner wrench rather than a conventional wrench.

This tool is required when disassembling cylinder housings, adjusting cylinder depth, or reassembling the lock body on D Series and L Series installations. Standard adjustable pliers or pipe wrenches can grip the spanner nut initially but quickly strip the notches, making future service impossible without the correct tool. Once the notches are stripped, the nut is difficult to remove without damaging the lock body, requiring housing replacement in many cases.

The 021415 replaced the older M504-341 spanner wrench. If a facility has older M504-341 tools in their kit, the 021415 is the current replacement that maintains the same function with the current ND and L Series spanner nut geometry.

39-029: Finish Selector Kit

The Schlage 39-029 finish selector kit is a collection of physical finish samples representing the full Schlage finish range. It is used at the specification stage of a project to select the correct finish designation before placing hardware orders.

Schlage finish codes use both BHMA designation numbers (626 for satin chrome, 619 for satin nickel, 622 for matte black, 605 for polished brass, and so on) and the older US designation system. Selecting a finish from a catalog image on a screen versus from an actual physical sample on the specified door material in the actual building lighting produces different results. The 39-029 finish selector kit provides physical sample chips that can be held against the door material in the actual installation environment, producing a finish selection that accounts for the actual ambient light rather than the catalog image.

The finish selection that causes the most post-installation rematch complaints: Architects and facilities managers who select finishes from catalog images or computer renders on projects where the actual doors are already installed and visible frequently discover that the selected finish looks different in person. Satin chrome (626) appears warmer in incandescent lighting and cooler under fluorescent lighting. Aged bronze finishes look more brown in high natural light and more gold under artificial lighting. Using the 39-029 finish selector kit with physical samples in the actual installation environment eliminates this post-installation finish mismatch. Hardware replacements due to finish dissatisfaction are not covered under warranty and represent avoidable cost.

40-015: Boring Bit 7/8 Inch

The Schlage 40-015 is a 7/8-inch diameter boring bit for the edge bore that accepts the latch assembly on cylindrical locks and deadbolts. The edge bore must be precisely sized to the latch body diameter: too small and the latch body cannot be inserted; too large and the latch body has excess play that causes misalignment and latch binding.

The standard 7/8-inch edge bore accommodates most standard Schlage latch assemblies. When a door's existing edge bore is the wrong size (too small for a new latch or damaged from a previous installation), the 40-015 restores the correct bore diameter. This bit is also used when installing Schlage hardware in doors that were previously bored for non-Schlage hardware with a different edge bore dimension.

40-026: Bushing for Jig 40-012

The Schlage 40-026 is a 1-1/2-inch bushing for the Schlage 40-012 installation jig. Installation jigs guide the boring bit to the correct position on the door face for the main crossbore without marking or measuring the door. The 40-026 bushing accepts the boring bit used for the 1-1/2-inch bore requirement on specific Schlage latch configurations.

40-029 and 40-030: Strike Marking Chisels

The 40-029 is a strike marking chisel for full-lip strikes. The 40-030 is a strike marking chisel for 1-1/8-inch by 2-3/4-inch strikes (the B Series deadbolt standard strike size). These are the most underused and most valuable installation tools in the Schlage accessory catalog.

A strike marking chisel is placed on the door edge with the lock's latch bolt in the extended position. When the door is closed against the chisel, the chisel face transfers an impression of the exact bolt position to the door frame. This impression shows the installer exactly where to chisel the mortise pocket in the frame for the strike. No measuring, no templating, no second-guessing the centerline. Strike misalignment is the most common cause of latch binding complaints on new installations, and it is also the most easily prevented with the correct marking tool.

The strike marking procedure that prevents every new-installation latch complaint: Before cutting any strike mortise pocket, use the appropriate strike marking chisel. Place the chisel on the latch face of the door with the latch extended and the door in the closed position. A firm push or two light hammer taps transfers the exact bolt outline to the frame. Chisel the mortise pocket to this outline. The strike plate covers minor surface marks. A single marking operation with the 40-029 or 40-030 produces a correctly positioned strike on the first cut, replacing a process that would otherwise require measuring the latch centerline, measuring up from the hinge centerline on the frame, and templating the strike from all these dimensions. Every missed dimension adds the possibility of a misaligned strike.

Schlage Installation Tools and Accessories: Complete Reference

Part Number	Description	Used On	When to Order
24002693	Lever removal tool, ND and L Series (updated ergonomic 2012 version)	ND Series cylindrical, L Series mortise	Any facility servicing Schlage ND or L Series; essential field tool
24341471	Lever removal tool, pack of 20	ND Series cylindrical, L Series mortise	Companies with multiple technicians servicing Schlage ND and L Series
021415	Spanner wrench, D Series knobs and L Series	D Series knobs, L Series mortise	Cylinder housing disassembly/reassembly on D and L Series
39-029	Finish selector kit with physical samples	All Schlage hardware with finish specifications	Pre-specification finish selection; renovation projects with existing hardware
40-015	Boring bit, 7/8 inch for edge bore	All Schlage latch assemblies using 7/8 inch edge bore	New installations; re-boring miscut or damaged edge bores
40-026	Bushing, 1-1/2 inch for 40-012 jig	40-012 installation jig	Specific bore requirements using Schlage jig system
40-029	Strike marking chisel for full-lip strikes	Full-lip strike installations	Every new lock installation; eliminates strike misalignment on first attempt
40-030	Strike marking chisel for 1-1/8" x 2-3/4" strikes	B Series deadbolt standard strikes	B Series deadbolt installations; replacement strike positioning
34-401	Home Secure Owner Key Envelopes (pack of 1000)	Key system documentation	Facilities maintaining physical key records for residents or owners
36-031	Trim collar	CL Series cabinet locks and cylindrical locks	Oversized bore covering; cosmetic damage around bore; CL cabinet lock installation
36-071	Trim ring and security insert pack	Cylindrical lock installations requiring additional trim ring	When trim ring is missing from an existing installation or damaged during service
38-031	Diameter adapter ring for 2-1/8 inch door prep	Cylindrical locks on doors with 2-1/8 inch bore	When door bore is 2-1/8 inch and closer-mounted trim requires specific ring adapter

Key Envelopes and Key System Documentation

The Schlage 34-401 Home Secure Owner Key Envelopes (pack of 1000) are the physical documentation component of a Schlage key system management program. Each envelope provides a space to record key codes, cut specifications, key holder name, and key number for a single key.

Key system documentation is the most overlooked element of commercial lock hardware maintenance. A building whose key system records are complete can be rekeyed efficiently when a key is lost, can add new openings to the existing key schedule without conflict, and can demonstrate key control compliance during security audits. A building with no key records must be surveyed from scratch for every rekeying event, which multiplies the labor and materials cost of what would otherwise be a simple change key swap.

The key control fact that determines rekeying costs for the next 20 years: A commercial building whose key system records are fully documented at installation costs roughly 30 to 50 percent less to rekey when a key is lost compared to a building with no records, because the locksmith can work from the documented key schedule rather than physically pulling and examining every cylinder. At 100 doors per floor on a multi-story facility, the difference in labor between working from records versus working without them is material. The Schlage 34-401 envelope system, combined with a maintained key schedule document, creates the records that make future rekeying operations predictable in cost and time. Most facilities skip this step at installation. Most facilities pay for it on the first rekeying event.

How to Integrate Schlage Padlocks into an Existing Key System

Integrating Schlage padlocks into an existing building key system follows the same process as adding any new Schlage lock to the system. Three steps determine how the padlock is keyed.

1. Identify the existing key system's keyway and master key schedule. The keyway must match between the padlock cylinder and the door hardware for the same key to operate both. If the building uses the Everest 29 keyway (restricted, patented), the padlock cylinder must also be specified as Everest 29. If the building uses a standard C keyway or other conventional keyway, the padlock cylinder is ordered to match.

2. Determine the keying level for the padlock. Should the padlock be operated by a change key (specific to one opening), masterkey (operates all locks at one master level), or grand master key (operates across multiple buildings or master groups)? The answer determines the pin tumbler combination used in the padlock cylinder.

3. Order the padlock with the cylinder specified to the key system requirements. Schlage padlocks can be ordered keyed to a specific Schlage key schedule when the order is placed through a Schlage distributor with access to the building's key bitting. For new buildings without an existing schedule, Schlage padlocks are ordered as part of the complete key system design.

Browse the complete Schlage padlocks catalog and installation tools and accessories catalog at Security Parts. For the complete Schlage commercial hardware range including B Series deadbolts, ND Series cylindrical locks, and L Series mortise locks, browse the Schlage commercial hardware catalog. Pre-order support is at 845-935-0301 or the contact page.

Why Choose Security Parts for Schlage Padlocks and Installation Tools

Masterkey integration guidance, hasp attack surface analysis, lever removal tool generation documentation, strike marking chisel benefit, and same-day shipping.

Masterkey Integration

We document that Schlage padlocks integrate into any existing Schlage key schedule, eliminating the second key ring for facilities staff. This specification value is the primary reason to choose Schlage padlocks over generic alternative

Hasp Attack Surface

We document that the hasp mounting fastener is the weakest link in most padlock installations, not the padlock. The double hinge plus shackle-less combination eliminates both shackle and single-hinge attack vectors.

Tool Generation Tracking

We document the August 2012 lever removal tool update so facilities know whether their existing M504-341 tool has been superseded by the 24002693. Using the old tool on new ND Series locks risks retention tab damage.

Same-Day Shipping

Most padlocks and tools ship same day from US warehouses. Call 845-935-0301 or use the contact page for key system integration and tool compatibility support.

What Makes Security Parts Different for Schlage Padlocks and Tools

We document the single-key building concept: Schlage padlocks with full-size cylinders integrate into any existing Schlage key system, eliminating separate padlock keys. No other parts supplier explains this integration value at the product level.
We document the key record documentation cost reduction: complete key records at installation reduce rekeying labor costs 30 to 50 percent versus buildings with no records. The 34-401 key envelope system is the record-keeping tool that makes this possible.
We document the lever removal tool generation change (M504-341 superseded by 24002693 in August 2012) so facilities using the old tool understand why the new tool is needed for Phase 1 ND Series and later locks.
We document the strike marking chisel as the most efficient way to prevent strike misalignment on new installations. No other parts supplier explains that the 40-029 and 40-030 eliminate the measurement steps that produce misaligned strikes.
We carry padlocks and tools alongside ND Series cylindrical lock parts, L Series mortise lock parts, B Series deadbolt parts, CL Series cabinet lock parts, and exit device parts for complete building hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

Schlage padlocks and installation tools appear alongside all Schlage door hardware in commercial facilities. A complete building service call typically covers door locks, padlocks, and the tools needed to service both.

For Schlage ND Series and ALX Series cylindrical lock parts for interior office and corridor doors in the same facility, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts for high-security entries, browse the mortise locks catalog. For Schlage B Series deadbolt parts for secondary exits and storage rooms, browse the deadbolts catalog. For Schlage CL Series cabinet lock parts for office furniture and filing cabinets in the same key system, browse the cabinet locks catalog. For LCN door closer parts on fire-rated corridor doors in the same building, browse the door closers catalog. For exit device parts on egress stairwells and fire exits, browse the exit devices catalog.

Browse the complete all products and parts catalog to source Schlage, Von Duprin, LCN, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Schlage Padlocks, Hasps and Installation Tools

Can Schlage padlocks be masterkeyed to the same system as Schlage door hardware?

Yes. Schlage padlocks use full-size Schlage cylinders that are compatible with any Schlage key system, including Everest 29 restricted keyway and conventional keyway systems. A building that uses Schlage door hardware on a master key schedule can specify Schlage padlocks to be keyed within the same schedule, so one master key opens all doors and all padlocks. Generic padlocks with small-format cylinders cannot be incorporated into a Schlage key system.

What is the difference between the Schlage 850410 and 855156 padlock?

The 850410 is a covered laminated steel padlock with a standard 1/4-inch hardened steel shackle and weather cover for all-weather use. The 855156 is a shackle-less padlock: a round 2-7/8-inch solid hardened steel body with a completely internal bolt that resists cutting, sawing, and prying attacks that target the shackle on standard padlocks. The 855156 is used with a hasp or lock box where the recessed bolt design makes shackle attacks impossible.

What is the Schlage 855118 hasp and what applications is it specified for?

The 855118 is a high-security hasp with a double hinge design (7-3/4 by 1-3/4 inches) for commercial storage, utility rooms, gate closures, and equipment enclosures. The double hinge prevents single-point prying attacks that defeat standard single-hinge hasps. Best combined with the 855156 shackle-less padlock: the two together eliminate both the shackle cutting attack and the single-point hasp prying attack.

What is the Schlage 24002693 lever removal tool and when is it used?

The 24002693 lever removal tool is the correct instrument for removing levers from Schlage ND Series cylindrical locks and L Series mortise locks without damaging the retention tab, rose, or chassis. An updated ergonomic version was introduced August 15, 2012 alongside the ND Series Phase 1 improvement project, including a bottle opener feature. Using substitute tools (screwdrivers or improvised picks) risks breaking the retention tab, which requires chassis replacement. The 24341471 is a pack of 20 for service companies.

What is the Schlage 021415 spanner wrench and what does it adjust?

The 021415 spanner wrench engages the spanner nut (a notched cylindrical collar) on Schlage D Series knobs and L Series mortise locks. It is required for cylinder housing disassembly and reassembly. Using pliers or pipe wrenches strips the spanner nut notches, making future service impossible without housing replacement. The 021415 replaced the older M504-341 wrench and is the current production tool for all D and L Series spanner nut operations.

What are the Schlage 40-029 and 40-030 strike marking chisels used for?

Strike marking chisels transfer the exact strike plate location from the door edge to the door frame during installation. The 40-029 is for full-lip strikes; the 40-030 is for 1-1/8-inch by 2-3/4-inch strikes (B Series deadbolt standard). The chisel is placed at the latch with the door closed, then tapped to transfer the impression to the frame, showing exactly where to cut the mortise pocket. Using a strike marking chisel eliminates the measurement steps that produce misaligned strikes, which is the most common new-installation latch complaint.

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LCN Sentronic, SEH Holder, Smoothee, SEM 7800 and Auto Equalizer Door Closer Parts: Complete Guide Tuesday, July 7, 2026

Security Parts carries parts for the LCN Sentronic fire and life safety closer series (3130SE, 4040SE, 4040SEH, 2310ME, 4310ME, 4410ME, 4310HSA, 4410HSA), the SEM 7800 Series magnetic holders, the 4210/4510 Smoothee high-security surface closers, and the Auto Equalizer pneumatic (2610, 4810, 4820, 4840) and electric (4630, 4640) operators. All Sentronic closers require voltage specification at ordering time (24V or 120V). The solenoid is not separately replaceable: it must be ordered as part of the track or cylinder subassembly. The SEH holder requires an opposite-side closer. SEH installation without a confirmed opposite-side closer is a life safety code violation on fire doors.

The LCN specialty product lines serve applications that standard surface closers cannot address: fire and smoke barrier doors that must hold open during normal hours and self-close on fire alarm, high-security environments where closer hardware must resist tampering, and multi-door corridors where a single pneumatic air supply powers dozens of doors simultaneously. Each of these product lines has unique parts requirements and ordering specifications that cannot be treated like standard surface-mounted closer parts.

Browse the complete LCN parts catalog at SecurityParts.com for all Sentronic, SEH, Smoothee, SEM 7800, and Auto Equalizer components. For the full LCN catalog including surface-mounted and overhead concealed closers, browse the commercial door closer parts catalog.

1972 Year LCN Sentronic technology was introduced (originally as 4010SE/4110SE)

24V or 120V Voltage options that must be specified at Sentronic ordering time

NFPA 101 Life Safety Code compliance required for all Sentronic fire door applications

225 lbs Maximum door weight capacity on LCN 4630/4640 electric Auto Equalizer

The LCN Sentronic System: How Fire Door Hold-Open Works

The LCN Sentronic system is built on a fundamental fire code requirement: interior fire and smoke barrier doors must be self-closing (they must close when not held open), but code allows them to be held open by an electromagnetic device connected to the building's fire alarm system. When the fire alarm activates, the current to the holding mechanism is interrupted and the door closes automatically under its own closer spring force.

This is the core operating principle of all Sentronic products. The door is held open during normal building hours by electromagnetic force. When fire alarm current interrupts, the electromagnetic hold releases and the door closer drives the door shut. No battery backup is involved: the fail-safe condition is always the de-energized state, which is the door closed. A power outage automatically closes all Sentronic-held doors, which is the correct life safety behavior.

Why fail-safe is always door-closed on Sentronic systems: Every Sentronic closer and holder is energized to hold the door open. Power interruption releases the hold. This is the opposite of many electronic access control systems where devices are energized to lock. The fail-safe design for fire door hold-open systems is intentional: if power fails, if the fire alarm activates, or if the wiring is cut, the door automatically closes and provides the rated fire separation. Any modification to a Sentronic system that changes this fail-safe direction (such as using a latching relay that keeps the door held even after power loss) creates a non-compliant fire door assembly that will fail inspection and can create life-safety liability.

LCN Sentronic Series Overview: Which Product for Which Door

3130SE

Overhead Concealed | Single Point Hold-Open

Overhead concealed Sentronic closer for 1-3/4 inch interior doors. Single point hold-open from 85 to 110 degrees. The 3130SEL extends hold-open range to 120 degrees fixed. Non-handed. Track assembly 4040SE-3038 also fits 3130SE, 4010SE, and 4110SE. Voltage must be specified (24V or 120V).

4040SE

Surface Mounted | Single Point | Closer and Holder

Heavy-duty non-handed, non-sized complete closer and holder for fire and smoke barrier doors. Single point hold-open from 85 to 110 degrees. Door held open until current interruption; single lever track arm. Requires no additional closer. Available 24V or 120V. Track assembly 4040SE-3038 replacement covers this series.

4040SEH

Holder Only | Must Have Opposite-Side Closer

Holder only: provides single-point hold-open but has NO closing mechanism. Must always be paired with an opposite-side UL-listed door closer. Non-handed. Single lever track arm. Track 4040SEH-3038 available in 24V or 120V. Momentary on/off switch board available for testing door release.

2310ME

Overhead Concealed | Multi-Point Hold-Open

Heavy-duty overhead concealed Sentronic with adjustable multi-point hold-open. Concealed in frame, single lever track arm concealed in door. Interior doors to 4'0". Full rack-and-pinion closer when hold-open not engaged or current interrupted. Handed. 24V or 120V. Conforms to NFPA 101.

4310ME

Surface Mounted Pull Side | Heavy Duty | Multi-Point

Heavy-duty surface mounted on hinge (pull) side. Ships with Swing-Free arm, track, track roller. Interior doors to 4'0". Full rack-and-pinion when hold-open not engaged or power interrupted. Swing-Free arm allows door to move without closer resistance when not in hold-open. 24V or 120V. Built-in on/off switch.

4410ME

Surface Mounted Top Jamb | Heavy Duty | Multi-Point

Surface mounted on top jamb (push side) with double-lever regular arm. Full rack-and-pinion when hold-open not engaged or power interrupted. Same application as 4310ME but for push-side mounting when hinge-side mounting is not possible. 24V or 120V. Ships with mounting plate and metal cover.

Sentronic Parts Reference: Voltage Selection and Key Replacement Components

The Most Critical Ordering Decision: 24V or 120V

Every Sentronic closer cylinder and track assembly is voltage-specific. Ordering the wrong voltage produces a unit that connects to the wrong wiring system and either fails to hold open (if 120V unit on 24V supply) or potentially damages the control board (if 24V unit on 120V supply). The voltage of the installed system must be confirmed before ordering any Sentronic replacement component.

The installed voltage is determined by the building's fire alarm or hold-open control panel. In most modern commercial installations, 24V DC or 24V AC is the standard because fire alarm systems operate at 24V. In older buildings, 120V wiring from the building's electrical system was used because early Sentronic systems predated 24V fire alarm standardization. When replacing a component in an older building, confirm at the existing wiring rather than assuming the voltage from the building's era.

The transformer that prevents the most common Sentronic installation mistake: When a 120V Sentronic unit is specified in a building whose fire alarm operates at 24V, the LCN 4040SE-3210 transformer reduces line voltage from 120V to 24V AC. It mounts on a plate for a 4-inch by 4-inch by 2-1/8-inch junction box. Many Sentronic installations that appear to fail immediately after replacement actually have a voltage mismatch: a 24V replacement cylinder was ordered for an existing 120V wiring system. Always check the transformer presence and voltage at the junction box before ordering a replacement cylinder.

Part Number	Description	Applies To	Notes
4040SE-3038	Track assembly (specify voltage and finish)	4040SE, 4040SEH, 3130SE, 4010SE, 4110SE	Shared across multiple Sentronic series. Voltage required.
4040SE-3210	Transformer, 120V to 24V AC	4040SE, 4040SEH	For junction box mount when 24V system uses 120V supply
4040SE-3436	On/Off switch assembly	4040SE	Controls hold-open function independently
4310ME-3351	On/Off switch assembly (specify 24V or 120V)	4310ME	Voltage-specific; must specify at ordering time
4410ME-3351	On/Off switch assembly (specify 24V or 120V)	4410ME	Voltage-specific; must specify at ordering time
SEH-3077T	Standard single (100 degree) holder arm	4040SEH	Non-handed; can combine with any 4040SE track
SEH-3034	Track roller, quiet low friction	4040SEH	Shoulder dimension X = 1/4 inch
SEH-168	Track slider, alloy metal	4040SEH	For use in SE series tracks only
SEH-81	Conduit quick-connector	4040SEH	Two-piece connector for 1/2 inch conduit

The Solenoid Subassembly Rule

The solenoid in all LCN Sentronic closers and holders is not a separately replaceable component. This is the single most important parts fact about Sentronic systems that is not documented in any supplier catalog in buyer-facing format. When a Sentronic closer fails to hold open (door closes immediately even with power applied), the diagnosis often points to the solenoid. The correct replacement is the track assembly or cylinder subassembly that includes the solenoid, not a standalone solenoid coil.

The 4040SE-3038 track assembly is the replacement unit that resolves solenoid failures on the 4040SE, 4040SEH, 3130SE, 4010SE, and 4110SE. It is ordered with voltage specification. No standalone solenoid replacement kit exists for these models. Ordering a solenoid coil separately, as some buyers attempt, produces a part that cannot be field-installed without the complete subassembly.

4310HSA and 4410HSA Sentronic: High-Traffic Passage Closers

The LCN 4310HSA and 4410HSA Sentronic Series occupies a different application niche from the fire door hold-open Sentronic products. Where the 4040SE, 3130SE, and 2310ME are fire-coded products for doors that must be kept closed during fire events, the 4310HSA and 4410HSA are electronically controlled closers designed for easy passage through high-traffic doors in normal building operations.

The 4310HSA and 4410HSA use an electronic hold-open function that allows staff or residents to pass through a door without fighting the closer spring force on every passage. A credential event, push-button signal, or occupancy sensor can trigger the hold-open, and the door closes automatically after the hold-open period expires. This is the correct specification for pharmacy pass-through doors in hospitals, resident wing corridor doors in assisted living, and high-traffic interior doors where physical effort is a barrier for specific user populations.

Both the 4310HSA and 4410HSA are surface mounted. The 4310HSA mounts on the hinge (pull) side. The 4410HSA mounts on the top jamb (push side). Parts for these series include voltage-specific cylinder assemblies and switch assemblies consistent with the broader Sentronic family.

LCN SEH Series Holder: The Critical Installation Requirement

The LCN SEH Series (including the 4040SEH) is a holder only device with no closing mechanism. This distinction is the most important life safety fact about the SEH Series and is responsible for more non-compliant fire door installations than any other LCN specification error.

SEH vs 4040SE: The Missing Closer

The 4040SE is a complete closer and holder in one unit. The 4040SEH is a holder only. When the fire alarm de-energizes the SEH's holding mechanism, the door must be closed by a separate door closer mounted on the opposite side of the door from the SEH. Without this opposite-side closer, the door hangs open when the SEH releases. A fire door assembly on a smoke or fire barrier that does not self-close is a non-compliant assembly and can result in the Authority Having Jurisdiction (AHJ) requiring immediate correction.

The SEH installation that passes initial inspection but fails under fire conditions: An SEH installation on a fire-rated door without an opposite-side closer may pass a visual inspection because the door appears to be on proper hardware. It fails functionally when the holding mechanism releases: the door does not close. This failure mode is only discovered during fire alarm testing, AHJ inspection, or an actual fire event. Any SEH installation must be confirmed to have an opposite-side UL-listed door closer before the fire door assembly can be considered compliant.

SEH Mounting and Configuration

The SEH Series mounts on the hinge pull side or stop face push side. The non-handed arm (SEH-3077T, standard single 100-degree holder arm) can be combined with any 4040SE series track, providing flexibility in mounting position. The track roller (SEH-3034) is the low-friction roller assembly with a 1/4-inch shoulder dimension X. The track slider (SEH-168) is the alloy metal slider used in SE series tracks.

LCN SEM 7800 Series Magnetic Holders

The LCN Sentronic SEM 7800 Series are electrically controlled door-holding magnets that are categorically different from Sentronic closers. The magnet holds the door open through direct magnetic attraction to a ferrous armature plate mounted on the door face. When the fire alarm de-energizes the magnet, the door releases and a separate door closer drives it shut.

SEM 7800 Mounting Options

The SEM 7800 Series offers three mounting configurations to address different door and corridor geometries:

Floor mount: The magnet mounts on the floor directly below the door edge. The armature plate mounts on the bottom of the door. Floor mounting is the cleanest aesthetic solution because the magnet is not visible on the wall or door face when the door is open.

Surface wall mount: The magnet mounts on the wall adjacent to the door. The armature plate is on the door face at the same height. Surface wall mounting is the easiest to install but leaves the magnet body visible on the wall.

Recessed wall mount: The magnet is recessed into the wall with only the face plate visible. This provides the lowest-profile wall appearance while maintaining the magnetic holding function.

The SEM 7800 armature alignment fact that prevents most holding failures: The SEM 7800 magnetic holding force is directly proportional to the alignment between the magnet face and the armature plate on the door. Even small misalignments of 1 to 2mm between the magnet face and armature reduce holding force significantly. When a SEM 7800 installation fails to hold a door reliably or releases under light force, the diagnosis is almost always armature misalignment rather than a failed magnet or wiring problem. Before diagnosing a failed magnet, check the alignment gap between the magnet face and armature plate when the door is in the hold-open position. The gap should be minimal and even across the full face. Adjusting the armature plate position restores full holding force without any parts replacement.

LCN 4210 and 4510 Smoothee: High-Security Closer Parts

The LCN 4210 and 4510 Smoothee Series are the surface-mounted high-security door closers in the LCN catalog. They are specified in correctional facilities, detention centers, psychiatric hospitals, and juvenile facilities where occupants may have motive and opportunity to defeat or damage door hardware.

The "Smoothee" designation, which has been part of the LCN naming convention for decades, refers to the smooth, tamper-resistant exterior of the closer body. Standard door closers have exposed adjustment valves, arm screws, and cover seams that provide leverage points for tampering. The Smoothee's design minimizes these attack surfaces.

4210 vs 4510 vs 2210

The 4210 is the standard high-security Smoothee, heavy-duty surface mounted with special components to minimize tampering and vandalism. The 4510 is the heavy-duty high-security version for applications requiring maximum closer durability alongside the tamper-resistant design. The 2210 is the overhead concealed version of the high-security closer, for applications where a concealed installation is preferred but still require tamper resistance. All three are Grade 1 and available in finishes appropriate for institutional environments.

Smoothee Arm and Valve Access

The Smoothee Series uses a restricted cover design that limits access to the adjustment valves and arm screw without special tools. This is intentional: easy valve access is the primary tampering vulnerability on standard door closers in correctional environments. When servicing a Smoothee in the field, confirm the correct tool is available before beginning work. Attempting to access valves or covers with standard tools risks damaging the tamper-resistant features that make the Smoothee appropriate for its specification environment.

LCN Auto Equalizer Operators: Pneumatic and Electric

The LCN Auto Equalizer operator lines serve a specific application: doors that need to assist manual opening without being fully automatic door openers. Where the Benchmark and Senior Swing operators open doors automatically when activated, the Auto Equalizer provides reduced opening force assistance using pneumatic or electric power. The result is a door that feels lighter to open without being power-operated in the sense that requires ADA guard rails or safety mats.

Pneumatic Auto Equalizer: 2610, 4810, 4820, 4840

The pneumatic Auto Equalizer series uses compressed air to equalize the door opening force. The 2610 is the most distinctive model: a single air supply unit that can power multiple doors simultaneously through pneumatic distribution lines. This multi-door capability makes the 2610 appropriate for large corridor projects where installing individual operators on each door would be prohibitively expensive.

The 4810 is the pneumatic series for primarily manual applications where occasional automatic assistance is needed. The 4820 is the low-energy ADA version providing controlled opening for accessible routes. The 4840 is the pneumatic multi-door solution for simultaneous control of several doors from a single air supply.

Electric Auto Equalizer: 4630 and 4640

The 4630 and 4640 use an electrohydraulic mechanism (motor-driven hydraulic pump) rather than compressed air. The 4630 allows manual opening to 170 degrees. The 4640 allows manual opening to 100 degrees.

Both the 4630 and 4640 are designed for doors up to 225 pounds and act as standard door closers in the event of power outage, maintaining the fail-safe closed behavior required on fire-rated egress doors. The 4630 and 4640 use a controller assembly (part 4640-3462 for the 4640) that manages the hydraulic operation and includes an on/off switch and hold-open adjustment.

The critical clutch assembly lubrication prohibition on 4630/4640: The LCN installation instructions for the 4630 and 4640 explicitly prohibit any form of lubricant contact with any part of the clutch assembly. The clutch is the mechanism that engages and disengages the motor-driven hydraulic system from the door arm during manual override. Oil or grease on the clutch prevents correct engagement and disengagement, producing erratic door behavior that mimics controller failure. Before diagnosing any 4630 or 4640 operational problem, confirm that no lubricant has been applied to the clutch area during a previous service visit.

For reveal depths between 4-1/2 inches and 8 inches, the 4630 requires the 4642 long arm. For reveal depths greater than 8 inches, consult the factory before ordering. This arm specification is distinct from all surface-mounted LCN closer arms and must be confirmed against the specific door reveal before any arm replacement order.

How to Identify the Correct Sentronic or Specialty Closer Before Ordering

Five pieces of information are needed before any Sentronic or specialty LCN parts order.

1. Series designation (4040SE, 4040SEH, 4310ME, 4410ME, 2310ME, 3130SE): On the label under the cover or on the cylinder body. This determines the parts catalog section.

2. Voltage (24V or 120V): At the wiring junction box or on the existing transformer. Voltage-specific components will not function if the wrong voltage is ordered.

3. Which component failed (track assembly, on/off switch, transformer, roller, slider): Track assembly failures: door does not hold even with power confirmed. Switch assembly failures: hold-open function cannot be tested or interrupted from the local switch. Roller failures: track noise or resistance on door swing.

4. For SEH: confirm opposite-side closer is present and UL-listed. Any SEH parts order should include verification that the opposite-side closer is still functional and compliant before the SEH is serviced.

5. For Smoothee: confirm available service tools before scheduling field work. The Smoothee's tamper-resistant design requires specific tools that may not be on a standard service truck.

Browse the LCN parts catalog at SecurityParts.com for all Sentronic, SEH, Smoothee, SEM 7800, and Auto Equalizer components. For the full LCN closer catalog including surface-mounted and concealed series, browse the commercial door closer parts catalog. For related exit device and alarm parts that appear on the same fire doors, browse exit alarm parts and exit device parts. Pre-order support is at 845-935-0301 or the contact page.

Why Choose Security Parts for LCN Sentronic and Specialty Closer Parts

Solenoid subassembly rule, SEH opposite-side closer requirement, 4630 clutch prohibition, voltage confirmation guidance, and same-day shipping on stocked parts.

Solenoid Subassembly Rule

We document that the Sentronic solenoid is not separately replaceable and must be ordered as part of the track or cylinder subassembly. This prevents the impossible-to-find standalone solenoid order.

SEH Compliance Warning

We document that the SEH holder requires an opposite-side UL-listed closer and that installing an SEH without one creates a non-compliant fire door assembly. No other parts supplier makes this explicit.

Voltage Guidance

We document the 24V vs 120V voltage selection requirement for every Sentronic parts order, and the transformer 4040SE-3210 as the resolution when voltage mismatch is discovered after installation.

Same-Day Shipping

Most Sentronic, SEH, and Auto Equalizer parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for voltage and series confirmation.

What Makes SecurityParts.com Different for These LCN Parts

We document the solenoid subassembly rule at the parts-ordering level. No buyer-facing parts supplier content anywhere explains that LCN Sentronic solenoids cannot be replaced standalone. This single fact prevents the most common impossible-to-complete Sentronic repair.
We document the fail-safe direction (energized-to-hold, de-energized-to-close) and the life safety implication of any modification that changes this. Sentronic systems that use latching relays to maintain hold after power loss are non-compliant, but this is not documented in buyer-facing content anywhere.
We document the SEH opposite-side closer requirement as a code compliance issue, not just an operational one. An SEH without a confirmed opposite-side closer is a non-compliant fire door assembly that can fail AHJ inspection.
We document the 4630/4640 clutch assembly lubrication prohibition. A service visit that lubricates the clutch produces erratic behavior that looks like a controller failure and generates an unnecessary controller replacement order.
We carry all LCN specialty parts alongside Von Duprin and Falcon exit device parts, exit alarm parts, electric strike parts, and Schlage cylindrical lock parts for complete fire door hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

Fire and smoke barrier doors that use LCN Sentronic or SEH holders also typically include exit devices, electric strikes for access-controlled fire door openings, and exit alarms on secondary egress doors.

For Von Duprin and Falcon exit device parts on fire-rated egress doors in the same building, browse the exit devices catalog. For Von Duprin Guard-X and Detex ECL exit alarm parts on fire door secondary exits, browse the exit alarms catalog. For Von Duprin electric strike parts on fire door frames with access control, browse the electric strikes catalog. For Schlage ND and ALX Series cylindrical lock parts on office and interior doors in the same facility, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on high-security entries in the same building, browse the mortise locks catalog.

Browse the complete all products and parts catalog to source LCN, Von Duprin, Schlage, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About LCN Sentronic, SEH, Smoothee and Auto Equalizer Parts

What is the difference between the LCN 4040SE and 4040SEH Sentronic?

The 4040SE is a combination closer and holder: it both holds the door open electronically and closes it automatically when fire alarm current is interrupted. It requires no additional closer. The 4040SEH is a holder only with no closing mechanism: it must always be used with an opposite-side UL-listed door closer. Installing an SEH without an opposite-side closer creates a non-compliant fire door assembly because the door will not self-close when the SEH releases.

What voltage do LCN Sentronic closers use and how do I specify it when ordering?

All LCN Sentronic closers are available in 24V AC and 120V AC. Voltage must be specified at ordering time because cylinder and track assemblies are voltage-specific. 24V is used with fire alarm systems that provide 24V output. 120V is used with older line-voltage wiring systems. The 4040SE-3210 transformer reduces 120V line voltage to 24V when a 24V system is connected to a 120V supply circuit.

What is the LCN Sentronic solenoid and can it be replaced separately?

The Sentronic solenoid is the electromagnetic coil that holds the door open when energized. It is not separately replaceable as a standalone field component on any LCN Sentronic model. It must be ordered as part of the track assembly subassembly (4040SE-3038 for the 4040SE, 4040SEH, 3130SE, 4010SE, and 4110SE). Always specify voltage when ordering the track assembly replacement.

What is the LCN 4210/4510 Smoothee and where is it used?

The 4210 and 4510 Smoothee are heavy-duty, high-security surface-mounted door closers with special tamper-resistant components designed for correctional facilities, detention centers, psychiatric hospitals, and other environments where hardware may be subject to deliberate damage. The 2210 is the overhead concealed version. All three are Grade 1. The Smoothee cover and valve access requires specific service tools not typically on a standard service truck.

What is the difference between the LCN 2610/4810/4820/4840 and 4630/4640 Auto Equalizer operators?

The 2610, 4810, 4820, and 4840 are pneumatically powered Auto Equalizers for primarily manual applications. The 2610 can power multiple doors from one air supply. The 4630 and 4640 are electrohydraulic (motor-driven) operators for single doors. The 4630 opens to 170 degrees; the 4640 opens to 100 degrees. Both electric models handle doors to 225 pounds and act as standard closers on power outage. The 4630/4640 clutch assembly must never be lubricated.

What is the LCN SEM 7800 Series and how does it differ from the Sentronic closer?

The SEM 7800 is an electrically controlled door-holding magnet only: no closer mechanism is included. It holds the door open through magnetic attraction to an armature plate on the door face and releases when fire alarm de-energizes the magnet. The door must already have a door closer to self-close on release. Available in floor mount, surface wall mount, and recessed wall mount. The most common SEM 7800 failure is armature misalignment, not magnet failure: check alignment before diagnosing electrical components.

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LCN 1000 Series and Overhead Concealed Door Closer Parts: 1260 1460, 2010 5010, 2030 5030 6030 and 3030 3130 Complete Guide Monday, July 6, 2026

Security Parts carries parts for the LCN 1000 Series surface-mounted closers (1260 and 1460) and the overhead concealed series including 2010/5010, 2030/5030/6030 Pacer, and 3030/3130. The 1000 Series are universal closers: both the 1260 and 1460 fit left and right hand doors without specifying handing. The arm screw 159 (1/4-20, 3/4-inch head) holds the arm to the spindle across all major LCN surface-mounted series. The regular arm 3077 works on 1260, 1460, 4010, 4020, and 4040 closers. Arms are not cross-compatible between the 1000 Series and the 4040XP. Cover part numbers follow the convention: series number followed by -72 (for example, 1460-72 for the 1460 cover). All overhead concealed series use cast iron cylinders and forged steel pistons with all-weather fluid.

The LCN product catalog covers considerably more than just the 4040XP. The 1000 Series surface-mounted closers are on more light commercial, educational, and healthcare interior doors than any other LCN surface-mounted line. The overhead concealed series: 2010, 5010, 2030, 5030, 6030, 3030, and 3130, cover institutional, aluminum storefront, and interior door applications where a visible surface-mounted closer is not acceptable architecturally. Each series uses different parts that are not cross-compatible with other series even within the same LCN catalog.

Browse the complete LCN parts catalog at SecurityParts.com. For the full LCN door closer and automatic operator catalog, browse the commercial door closer parts catalog.

30-year Limited warranty on the LCN 1460 Series closer

15-year Limited warranty on 2030/5030/6030 and 3030/3130 Series

1-3/4" Minimum transom width for 2030/5030/6030 Pacer concealed installation

Grade 1 ANSI/BHMA A156.4 certification on all series covered in this guide

Surface Mounted vs Overhead Concealed: Choosing the Right LCN Series

Every LCN door closer falls into one of two fundamental categories: surface mounted (the closer body is visible on the door face or header) or overhead concealed (the closer mechanism is hidden inside the door, frame, or transom). The choice between them is driven by the application, the architectural requirement, and the door construction. Parts are never cross-compatible between the two categories.

Surface mounted closers are faster to install, easier to service, and carry lower installed cost. The closer body, arm, and cover are all visible on the door face. The 1000 Series (1260 and 1460) and the 4000 Series (4040XP, 4040, 4000) are both surface-mounted. They are the correct choice for any commercial door where concealment is not required.

Overhead concealed closers hide the mechanism inside the door or frame, leaving only the arm or track visible or nothing visible at all when the door is closed. They are specified on high-end architectural projects, historic renovations where exposed hardware is not acceptable, healthcare corridors where cleaning staff cannot trap dirt behind visible closer bodies, and aluminum storefront doors where the closer must fit within the narrow tube frame. The 2010, 5010, 2030, 5030, 6030, 3030, and 3130 Series are all overhead concealed.

LCN 1000 Series Surface Closers: 1260 and 1460

The LCN 1000 Series contains LCN's most versatile surface-mounted closers. All standard 1000 Series models are universal: they install on either hand of door and in regular arm, parallel arm, or top jamb configurations without specifying handing at order time. This universality is the primary specification advantage over the 4000 Series (which requires handing specification on most models) and is why the 1000 Series appears so frequently on quick-turn projects and retrofit applications.

LCN 1260 Series

Light-to-Medium Duty | Universal | 20-Year Warranty

Adjustable spring sizes 1 to 5. Interior doors to 4'6", exterior to 3'6". Non-handed cylinder assembly. Peel-n-stick template for quick installation. Optional Quick Fix bracket kit for retrofit on existing closer footprint. Slim line optional cover. 20-year limited warranty. ANSI/BHMA A156.4 Grade 1.

LCN 1460 Series

Medium Duty | Universal | 30-Year Warranty

Adjustable spring sizes 1 to 6 with patented Green Dial system. Interior doors to 5', exterior to 4'. Ships with 1461-3071 cast iron cylinder, 1460-3077 regular arm, 1460-62PA parallel arm shoe, 1460-72 slim line cover. Self-reaming and tapping screws (SRT) standard. ADA compliant. 30-year limited warranty.

LCN 1000 Series Parts Reference

Part Number	Description	Applies To	Notes
1461-3071	Cast iron cylinder assembly	1460 Series	Non-handed. Includes screw pack (SRT standard)
1460-3077	Regular arm (non-handed)	1460 Series	Hinge pull side mounting standard arm
1460-62PA	Parallel arm shoe	1460 Series	Required for parallel arm push side mounting
1460-72	Slim line plastic cover	1460 Series	Standard cover shipped with 1460
1460-159	Arm screw (1/4-20)	1460 Series	3/4" head diameter, holds arm on spindle
1260-159	Arm screw (1/4-20)	1260 Series	Same screw dimensions as 1460-159
1260-72	Standard cover	1260 Series	Cover part number: series + -72 convention
3077	Regular arm (non-handed)	1260, 1460, 4010, 4020, 4040	Ships with most LCN surface-mounted closers

The LCN Cover Part Number Convention: Series + -72

The LCN plastic cover part number follows a consistent convention across all surface-mounted series: the model series number followed by -72. The 1460 cover is 1460-72. The 4040 cover is 4040-72. The 4020 cover is 4020-72. The 4110 cover is 4110-72. This convention applies across all standard surface-mounted LCN series and eliminates the need to look up the cover part number separately when you know the closer series. Not all LCN closers have the same shape cover, so even though the naming convention is consistent, the physical cover is series-specific and cannot be substituted between series.

The casting number on the cylinder that is NOT the part number: Many LCN cylinders have casting or forging numbers stamped or raised on the surface, such as "71" or "320G". These are manufacturing reference numbers, not part numbers or model identifiers. A technician who reads "71" on the cylinder body and tries to order "71" as a replacement part will not find it in any catalog because it is not a part number. The correct method for identifying replacement parts is to find the model label (usually a sticker on the cylinder body under the cover) and use the model number from the label. The model number is under the cover on a sticker. For mechanical products, the month and year of manufacture is stamped near the packing nut at the base of the pinion where the arm attaches.

The Green Dial Spring Adjustment on the 1460

The LCN 1460 Series features the patented Green Dial spring power adjustment system. Unlike older LCN closer designs where spring power adjustment required the correct-size stamped cylinder from the factory, the Green Dial allows field adjustment of spring power from size 1 through size 6 without requiring a different cylinder. Turning the Green Dial clockwise increases spring power (heavier closing force). Counterclockwise decreases it. This field adjustment eliminates the need to order a replacement cylinder when the spring power setting needs to change after installation, for example when a door adds a gasket that increases resistance and needs more closing force to latch reliably.

Arm Cross-Compatibility: What Works Where

LCN closer arms are machined to the specific spindle dimensions of each closer series. The spindle size and shape differs across models. The spindle on the 1260 and 1460 is different from the spindle on the 4040XP. An arm ordered for the 1460 Series will not fit a 4040XP closer. The 3077 regular arm works on the 1260, 1460, 4010, 4020, and 4040 (non-XP) closers. It does not work on the 4040XP, 4110, 4040SE, or any overhead concealed series.

The arm that looks identical but will not fit: A 1460 arm and a 4040XP arm appear almost identical from outside the package. Both are cast metal with the same general profile. The difference is in the spindle engagement hole, which is machined to the specific spindle geometry of the series. A 1460 arm installed on a 4040XP spindle will not seat correctly and will either strip the spindle or fail to transmit the spring force to the door. Always confirm the series from the label under the cover before ordering any replacement arm.

LCN 2010 and 5010 Series: Heavy-Duty Overhead Concealed for Institutional Applications

The LCN 2010 and 5010 Series are the heaviest-duty overhead concealed closers in the LCN catalog, specifically designed for institutional, high-traffic applications where complete concealment and maximum durability are both required. Hospitals, government buildings, correctional facilities, and university buildings with high daily cycle counts and abuse resistance requirements are the typical 2010/5010 specification environments.

2010 Series: Concealed in Frame and Door

The 2010 Series conceals both the cylinder in the door frame and the track in the door. From the finished side, the door shows only a clean face with no visible hardware at all when the door is in the closed position. This complete visual concealment is the defining specification feature of the 2010 and is why it is used in high-end institutional applications where exposed hardware is not acceptable.

The 2010 requires a mortise pocket in the door for the track and a mortise pocket in the frame for the cylinder. This door preparation requirement means the 2010 must be specified during door manufacturing, not retrofitted to standard doors without significant field work.

5010 Series: Cylinder Concealed in Frame, Double-Lever Arm Exposed

The 5010 shares the 2010's cylinder concealed in the door frame but uses an exposed double-lever arm on the door face rather than a concealed track. The exposed arm makes field service considerably easier: the arm is accessible without removing the door from the frame. The 5010 is the correct choice when concealment of the cylinder is required for security reasons (as in correctional applications where an exposed closer body could be defeated) but a fully concealed track is not required by the specification.

Both the 2010 and 5010 meet ANSI/BHMA A156.4 Grade 1 and ADA reduced opening force requirements. Both are designed for aluminum, hollow metal, or wood doors and frames and can be used with hinge or pivot mounted doors.

LCN 2030, 5030, and 6030 Pacer Series: Overhead Concealed for Aluminum Transoms

The LCN Pacer 2030/5030/6030 Series is the overhead concealed closer solution for narrow aluminum transom frames. The minimum transom width for Pacer concealment is 1-3/4 inches: the same minimum stile width that defines aluminum storefront hardware throughout the commercial door hardware industry. This is not coincidental. The Pacer was engineered to fit inside standard aluminum storefront frame sections, which is why it is the standard specification for overhead concealed closers on aluminum commercial entries.

2030, 5030, and 6030 Differences

Series	Mounting	Arm Type	Door Action	Spring Sizes
2030	In frame, track in door	Forged steel single-lever arm	Single acting (push or pull)	Adjustable 1 to 5
5030	In frame, exposed double-lever arm	Forged steel double-lever arm	Single acting	Adjustable 1 and 3 to 6
6030	In frame, track in door	Forged steel single-lever arm	Double acting (swings both ways)	Adjustable 1 to 5

The 5030 Series arm joints and shoe adapt to uneven trim, making it the preferred choice on aluminum storefront installations where the frame alignment is not perfectly consistent. On a standard aluminum door with a precisely manufactured frame, the 2030 concealed track arm is typically preferred for aesthetic reasons. On doors where field conditions introduce uneven trim, the 5030's adaptive arm joints accommodate the variance.

Pacer Series Construction

All three Pacer series use the same internal construction: a cast iron cylinder, a one-piece forged steel piston, a high-efficiency full-complement low-friction bearing, tamper-resistant regulating screws, and all-weather fluid. The spring power and latch speed adjustments are independent for either swing direction on all three series. The backcheck and general speed adjustments are common for both swings. All three are UL and cUL listed for self-closing doors without hold-open and carry a 15-year limited warranty.

The independent spring adjustment that most technicians adjust incorrectly: The 2030, 5030, and 6030 have separate spring power and latch speed adjustments for each swing direction. This means you can set the closing speed differently for the opening swing and the closing swing independently. On a double-acting 6030, this allows a door to open and close at different speeds in each direction, which is useful on service corridor doors where traffic in one direction is more consistent than the other. Most technicians adjust only the general closing speed screw without realizing the latch speed is a separate independent adjustment. A door that closes quickly but does not latch reliably almost always has a latch speed set too low, not a spring power issue.

LCN 3030 and 3130 Series: Overhead Concealed for Interior Doors

The LCN 3030 and 3130 Series are overhead concealed closers specifically designed for interior doors in medium- to high-traffic areas, mounted within the standard 1-3/4 inch interior door thickness. Where the 2030/5030/6030 Pacer fits in aluminum transom frames, the 3030/3130 fits within the door itself.

3030 vs 3130: Arm Style and Concealment Level

The 3030 Series conceals the cylinder in the door but uses an exposed double-lever arm on the door face. The arm joints adapt to uneven trim. The 3030 uses a non-handed cylinder, simplifying parts ordering when handing is uncertain.

The 3130 Series achieves complete concealment with both the cylinder in the door and a single-lever arm connected to a track and roller assembly that is also concealed within the door when the door is in the closed position. The only visible component on a 3130 installation is the roller in the track, and this is visible only when the door is open. From the closed-door view, there is no visible hardware at all. The 3130 uses a handed cylinder (right hand or left hand must be specified at ordering time).

3130 Track Roller: The Critical Wear Component

The 3130 track roller assembly is the most frequently replaced component on the 3130 Series. The roller travels in the track on every door cycle and wears over years of use. The standard track roller is part 3130-3034 (standard closing, aluminum finish). The hold-open track roller is part 3130-3034H (allows the door to hold open at a specified angle). When the door begins to not close fully or drifts open from a previously reliable closing cycle, the track roller is the first replacement candidate before diagnosing the cylinder.

The 3130 door that drifts open after years of reliable service: A 3130 installation that has been closing correctly for years and then begins to not fully close is almost always a worn track roller, not a failed cylinder or spring. The roller surface wears progressively until it no longer provides the friction needed to convert the cylinder's spring force into complete door closure. Replacing the track roller restores closing function without touching the cylinder. Many technicians diagnose a failing 3130 as a cylinder failure, replace the cylinder, and see no improvement because the roller was the actual problem.

3030 and 3130 Sizing

Both the 3030 and 3130 are sized closers, meaning the cylinder size must be specified at order time rather than being field-adjusted like the 1460's Green Dial system. The size number refers to the spring power, which determines the door width the closer can control. The 3130 size designation uses a single digit suffix: 3131 is size 1, 3132 is size 2, 3133 is size 3. Size 3 covers interior doors to 3 feet 2 inches. For a door wider than 3 feet 2 inches, a larger size must be specified at the time of ordering. Getting the size wrong means returning the closer for the correct size cylinder.

Overhead Concealed Closer Comparison: Which Series for Which Application

Series	Concealment Location	Arm	Door Type	Traffic Level	Warranty
2010	Cylinder in frame, track in door	Fully concealed	Aluminum, HM, wood	High/institutional	LCN standard
5010	Cylinder in frame	Exposed double-lever	Aluminum, HM, wood	High/institutional	LCN standard
2030	Cylinder in frame, track in door	Single-lever concealed	Aluminum 1-3/4" transom	High/institutional	15-year
5030	Cylinder in frame	Double-lever exposed (adaptive)	Aluminum 1-3/4" transom	High/institutional	15-year
6030	Cylinder in frame, track in door	Single-lever concealed	Aluminum, double acting	High/institutional	15-year
3030	Cylinder in door	Exposed double-lever (adaptive)	1-3/4" interior door	Medium to high	15-year
3130	Cylinder in door, track in door	Fully concealed (handed)	1-3/4" interior door	Medium to high	15-year

What Fails First on These LCN Closers

Surface Mounted 1000 Series

Arm screw 159: The most common service item on any 1000 Series installation. As the closer cycles thousands of times, the vibration from the arm's operating forces loosens the arm screw. When loose, the arm spins on the spindle instead of transmitting spring force to the door. The door then either fails to close fully or slams shut. Checking and retorquing the arm screw as a maintenance item eliminates most 1000 Series service calls.

Cover damage: The 1000 Series plastic cover takes environmental and cleaning chemical exposure that cracks or discolors the cover over time. The cover (part 1260-72 or 1460-72) is a cosmetic replacement that requires no tool beyond a standard screwdriver. Always confirm the series before ordering the cover replacement.

Fluid leak: A surface-mounted LCN closer that is closing too fast and slamming despite adjustment attempts has almost certainly lost hydraulic fluid. Fluid loss makes the valve regulation system ineffective. A replacement cylinder assembly is the correct part, not additional valve adjustment. Continued adjustment on a leaking cylinder body does not restore controlled closing speed.

Overhead Concealed Series

3130 track roller: Progressive wear over high-cycle use. Symptom: door that previously closed correctly now drifts open or does not fully close. Replace the track roller before diagnosing the cylinder.

2030/5030 roller assembly: The roller assembly in the Pacer series is the interface between the arm and the door. It can seize or develop play from aluminum oxide contamination on aluminum door surfaces. Annual lubrication of the roller assembly with a dry-film or silicone-based lubricant prevents most premature roller failures on 2030/5030 installations.

Arm joints on 5030 and 3030: The adaptive arm joints on the 5030 and 3030 contain a socket-and-ball mechanism that allows the arm to accommodate uneven trim. These joints can wear or corrode, losing the flexibility range that makes the adaptation possible. A 5030 or 3030 installation that begins to bind or produce door closing resistance despite correct cylinder adjustment usually has worn arm joints requiring arm replacement.

Browse the complete LCN parts catalog at SecurityParts.com for all 1000 Series, 2010/5010, 2030/5030/6030, and 3030/3130 components. For the full LCN door closer catalog including the 4040XP, Sentronic, and Smoothee series, browse the commercial door closer parts catalog. Pre-order support is at 845-935-0301 or the contact page.

Why Choose Security Parts for LCN 1000 Series and Overhead Concealed Parts

Casting number warning, arm cross-compatibility guide, 3130 track roller failure diagnosis, Pacer independent speed adjustment, and same-day shipping on stocked parts.

Casting Number Warning

We document that casting numbers like "71" or "320G" stamped on cylinders are NOT part numbers. Most technicians try to order by this number and fail. We point to the model label under the cover.

Arm Cross-Compatibility

We document that 1460 arms and 4040XP arms look identical but are not interchangeable due to different spindle geometries. This prevents the most common wrong-arm return on 1000 Series service calls.

3130 Track Roller Diagnosis

We document that a 3130 that stops closing correctly is almost always a worn track roller, not a cylinder failure. Replacing only the roller restores function at a fraction of the cost of cylinder replacement.

Same-Day Shipping

Most 1000 Series, Pacer, and 3030/3130 parts ship same day. Call 845-935-0301 or use the contact page for series identification support.

What Makes Security Parts Different for These LCN Parts

We document the casting number trap: "71" or "320G" on the cylinder is a manufacturing number, not a part number. Every technician who has tried to order by this number and failed needs this explained before placing an order.
We document the series + -72 cover part number convention. Knowing that 1460-72 is the 1460 cover eliminates the need to look up cover part numbers separately for any standard LCN surface-mounted closer.
We document the 3130 track roller as the first-check replacement for any 3130 that stops closing correctly, preventing unnecessary cylinder replacements on what is typically a simple roller wear failure.
We document the Pacer 2030/5030/6030 independent latch speed adjustment. A door that closes fast but does not latch has a latch speed problem, not a spring power problem. Most technicians adjust the wrong screw.
We carry LCN closer parts alongside Von Duprin and Falcon exit device parts, electric strike parts, Schlage cylindrical lock parts, and mortise lock parts for complete door system service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

LCN door closers appear on every fire-rated egress door alongside exit devices and electric strikes. The same building that uses 1460 Series surface closers on office doors uses 2030 Pacer closers on aluminum storefront entries and 3130 concealed closers on high-end architectural interior doors.

For Von Duprin and Falcon exit device parts on egress doors in the same building, browse the exit devices catalog. For Von Duprin electric strike parts on controlled entry doors in the same facility, browse the electric strikes catalog. For Von Duprin complete exit device and alarm parts, browse the Von Duprin catalog. For Schlage ND and ALX Series cylindrical lock parts on secured interior doors in the same building, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on high-security entries in the same facility, browse the mortise locks catalog.

Browse the complete all products and parts catalog to source LCN, Schlage, Von Duprin, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About LCN 1000 Series and Overhead Concealed Closer Parts

What is the difference between the LCN 1260 and 1460 Series door closers?

Both are universal surface-mounted closers that fit either hand of door without specifying handing at ordering time. The 1260 is light-to-medium duty, adjustable spring sizes 1 to 5, interior doors to 4'6", 20-year warranty. The 1460 is medium duty, adjustable spring sizes 1 to 6 with the patented Green Dial, interior doors to 5', 30-year warranty. Both use the arm screw 159 and the regular arm 3077 for hinge pull side mounting.

What is the LCN arm screw 159 and where does it fit?

The arm screw 159 is a 1/4-20 machine screw with a 3/4-inch diameter head that holds the closer arm on the spindle. It is used across major LCN surface-mounted series: ordered as 4040-159 for the 4040XP, 1460-159 for the 1460, 1260-159 for the 1260, etc. A loose arm screw causes the arm to spin on the spindle, producing a door that drifts open or fails to latch. Retorquing the arm screw resolves most arm-related closer failures before any cylinder replacement is needed.

What is the difference between the LCN 2010 and 5010 Series overhead concealed closers?

The 2010 Series conceals both the cylinder in the frame and the track in the door, providing complete concealment. The 5010 Series conceals the cylinder in the frame but uses an exposed double-lever arm on the door face. Both are heavy-duty Grade 1 closers for institutional high-traffic applications, meeting ADA reduced opening force requirements. Parts are series-specific and not cross-compatible with the 3030/3130 or 2030/5030/6030 Series.

What is the LCN 2030/5030/6030 Pacer Series and when is it used?

The Pacer Series is overhead concealed closers designed for concealment in aluminum transoms with a minimum 1-3/4-inch width. The 2030 uses a concealed track in the door with a single-lever arm. The 5030 uses an exposed double-lever arm with adaptive joints for uneven trim. The 6030 is a double-acting version with concealed track for doors that swing both ways. All three carry a 15-year warranty, are Grade 1, and ADA compliant.

What is the difference between the LCN 3030 and 3130 Series door closers?

Both are overhead concealed closers for 1-3/4-inch interior doors in medium- to high-traffic areas. The 3030 conceals the cylinder in the door but uses an exposed double-lever arm. The 3130 achieves complete concealment with a concealed single-lever arm and track roller assembly, showing no visible hardware when the door is closed. The 3130 is handed (RH or LH must be specified). Both carry a 15-year warranty and meet Grade 1 and ADA requirements.

How do LCN closer arms work and are they interchangeable between series?

LCN arms are machined to the specific spindle geometry of each closer series. Arms are not cross-compatible between series. The 1460 arm will not fit a 4040XP because the spindle is a different size and shape. The regular arm 3077 works on the 1260, 1460, 4010, 4020, and 4040 but not on the 4040XP, 4110, or any concealed series. Always confirm the series number from the label on the cylinder body under the cover before ordering any replacement arm.

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Von Duprin 75, 78, 88, 94/95 INPACT and 54 Series Mullion Parts: Complete Replacement Guide Friday, July 3, 2026

Security Parts carries parts for the Von Duprin 75 and 78 Series pushpad devices (70 Series family), the 88 Series wide stile crossbar, the 94/95 INPACT recessed push pad series, and the 54 Series mullion line. The 75 is narrow stile; the 78 is wide stile. Both share the 70 Series QEL quiet electric latch option. The 88 Series crossbar tube (part 967738) is 42 inches and shared with the 55 Series, field-cut to size. The 88 lever arm is handed (050438 RH, 050439 LH); the dogging pin spring in the arm is a separate replaceable component. The INPACT 94/95 is a recessed push pad device for impact reduction. Mullion stabilizers (part 154) must be installed on every mullion to prevent security bypass via deflection.

Von Duprin's exit device catalog is broader than most facilities managers realize. Beyond the 98/99, 33A/35A, 22, and 55 Series covered elsewhere, there are four additional series that address specific application challenges: the 70 Series (75 narrow stile and 78 wide stile pushpad devices), the 88 Series (wide stile crossbar), the 94/95 INPACT Series (recessed push pad for impact-prone environments), and the 54 Series mullion line that enables rim devices on double-door openings.

Browse the complete Von Duprin parts catalog at SecurityParts.com for all series with interactive diagrams. For the full exit device catalog including Falcon alongside Von Duprin, browse the commercial exit devices catalog.

42" 88 and 55 Series crossbar tube length, field-cut to fit

4-1/2" Minimum stile width required for the 88 Series wide stile device

QEL Quiet Electric Latch Retraction option on 70 Series and 94/95 INPACT

154 Mullion stabilizer part number, prevents security bypass via deflection

Von Duprin 70 Series: The 75 and 78 Pushpad Family

The Von Duprin 70 Series is the most recent generation of the Von Duprin pushpad exit device family, covering the 75 (narrow stile) and 78 (wide stile) models. These are positioned between the economy 22 Series and the premium 98/99 Series, offering heavy-duty construction for warehouse, industrial, office, multifamily, retail, and commercial real estate applications where the highest specification of the 98/99 is not required.

Von Duprin 75 Series

Narrow Stile | Pushpad | Heavy Duty

Narrow stile pushpad device for aluminum storefront and narrow frame commercial doors. Heavy-duty construction for warehouse, industrial, multifamily, retail, and commercial real estate. Available in rim, SVR, CVR, and wide door cable configurations. Supports QEL, RX, and E8875 electronic options. Fire-rated by adding F suffix. Field-reversible handing. Shares catalog (108004) with 78 Series and 70 Series QEL parts manual.

Von Duprin 78 Series

Wide Stile | Pushpad | Heavy Duty

Wide stile pushpad device for standard hollow metal and wood commercial doors. Same application markets as the 75 but for wide stile door constructions. Available in rim, SVR, CVR, and wide door cable configurations. Full electronic option range matching 75 Series. Includes QEL quiet electric latch retraction option for applications where latch retraction noise is a concern.

70 Series Quiet Electric Latch Retraction (QEL)

The QEL option is the most important specification detail on the 70 Series (75 and 78) and 94/95 INPACT Series. Standard electric latch retraction (EL) on Von Duprin devices uses a solenoid that produces a distinct mechanical click when the latch retracts. In healthcare corridors, educational facilities, and quiet institutional environments, this noise is a complaint trigger from clinical staff and building management.

The Quiet Electric Latch Retraction (QEL) addresses this by using a motorized, slower-action latch retraction mechanism that significantly reduces the noise of electric latch operation. The QEL is available on devices sold after October 2014 on new installations. For pre-October 2014 devices, modular conversion kits allow upgrading existing non-EL panic or fire-rated devices to QEL without replacing the entire exit device.

The QEL conversion kit that most facilities don't know exists: The Von Duprin 70 Series QEL modular conversion kit allows a panic or fire-rated exit device sold after October 2014 to be upgraded to quiet electric latch retraction in the field without replacing the complete exit device. This is the most cost-effective upgrade path for healthcare and educational facilities where a standard EL click is generating complaints but a full device replacement is not budgeted. The conversion kit specifically applies to non-EL panic devices or non-EL fire-rated devices sold after October 2014. Devices sold before October 2014 require full device replacement for QEL.

70 Series Electronic Options

The 70 Series (75 and 78) supports the following electronic options. These are specified at ordering time and are not field-added without conversion kits.

Option Code	Function	Application
QEL	Quiet Electric Latch Retraction	Healthcare, education, quiet institutional environments requiring electric latch with minimal noise
RX	Request to Exit switch	Access control integration: switch in exit device signals the controller when push bar is pressed
E8875	External electric control	Allows device to pair with access control system, fire alarm system, or remote switching station
-F suffix	Fire-rated version	Any 70 Series device on a fire-rated door assembly

Von Duprin 88 Series: Wide Stile Crossbar Parts

The Von Duprin 88 Series is a wide stile crossbar exit device for standard commercial hollow metal and wood doors. Where the 55 Series is the narrow stile crossbar for aluminum storefronts, the 88 is the wide stile crossbar for doors with 4-1/2 inches or more of stile width. The 88 Series has been in production since at least the 1950s and remains in the Von Duprin catalog because it serves two applications that pushpad devices cannot: traditional-looking wide stile installations where the crossbar aesthetic is an architectural requirement, and non-standard door widths where the field-cuttable crossbar can be sized precisely without special ordering.

88 Series Crossbar Tube: Part 967738

The Von Duprin 88 and 55 Series share the same crossbar tube (part 967738). The tube is 1 inch in diameter and 42 inches long. It ships at 42 inches and must be field-cut to the appropriate length for the specific door width using a tubing cutter or hacksaw. One side of the tube comes pre-cut with a slot for the wedge tite screw opening. This pre-cut slot must be positioned correctly when the crossbar is installed in the lever arm.

The crossbar measurement that prevents a second cut: When cutting the crossbar to length, measure from the outer edge of the left lever arm connection point to the outer edge of the right lever arm connection point, then add approximately 1/4 inch on each side for the connection overlap. Cutting the bar to the door width alone without accounting for the lever arm overlap produces a bar that is too short to engage both lever arms correctly. A bar that is too short cannot be lengthened. Measure twice, cut once.

Tube Attaching Ring and Wedge Tite Screw

The tube attaching ring (part 090021) fits over each lever arm and is expanded by the wedge (part 88R90) and the wedge tite screw (part 88R100) to clamp the crossbar securely to the arm. The ring measures 15/16 inch long by 13/16 inch diameter. When tightened, the ring expands and holds the crossbar parallel to the door without visible fasteners on the front face of the bar.

A rattling crossbar or a crossbar that has dropped at one or both ends is almost always caused by loose wedge tite screws, not by failed components. The correct service is to tighten the wedge tite screw in each lever arm with a drop of blue thread-locker applied before final tightening. Thread-locker prevents vibration-induced loosening on high-cycle doors without making the screw impossible to remove for future service.

88 Series Lever Arm Assemblies

The 88 Series lever arm connects the crossbar to the center case mechanism. The lever arm is handed: right hand is part 050438, left hand is part 050439. Each arm includes the wedge, wedge ring, wedge tite screw, and dog screw. Some kits also include the axle.

Lever arm replacement is needed when the dogging screw in the arm has stripped (the most common failure reason according to field service records), when the arm is physically bent from impact, or when the axle has failed. The axle is a separately replaceable component: the current axle design (introduced around 1990) snaps together and replaces the older design that used allen-wrench-assembled axles. When replacing an axle, the separation tool is required to disassemble the current snap-together style.

The 88 Series Dogging Pin: The Failure Nobody Diagnoses

The Von Duprin 88 Series uses a dogging pin mechanism located on the underside of the active lever arm to hold the crossbar in the depressed position during business hours. This is different from the hex key slot used on the 22, 33A, and 98/99 Series. The dogging pin has an internal spring that provides the retention force.

The spring inside the dogging pin that saves a $150 lever arm replacement: When an 88 Series crossbar will not stay in the dogged position (the bar pops back up when the hex key is removed), most technicians diagnose a failed lever arm and order a full replacement assembly. The actual failure is almost always the spring inside the dogging pin on the underside of the active lever arm. This spring is a separately replaceable component. Replacing only the dogging pin spring restores dogging function at a fraction of the cost of a lever arm assembly. Before ordering any lever arm replacement on an 88 Series with a dogging failure, check the dogging pin spring first.

88 Series Field-Reversible Handing

The 88 Series is field-reversible for handing. This means the device can be converted from right-hand to left-hand or vice versa in the field without returning the device for a factory conversion. This saves the project when door handing has been incorrectly specified: a Friday afternoon discovery that the device is the wrong hand can be corrected on-site rather than requiring a return and reorder. Confirm handing before installation regardless, but this reversibility is a genuine specification advantage over devices requiring factory handing.

88 Series Mounting Screw Package

The 88 Series mounting screw package (part 900503) includes 12 screws in two types: 6 machine screws and 6 hybrid screws (for the 88C/C or E/C mounting configurations). Always use the correct screw type for the specific mounting configuration. Using only machine screws on a hybrid mounting leaves the device with reduced pull-out resistance at the center case anchor points.

Von Duprin 94/95 INPACT Series: Recessed Push Pad Parts

The Von Duprin INPACT 94/95 Series is the only fully recessed exit device in the Von Duprin commercial line. Instead of a push pad that projects outward from the door face, the INPACT push pad sits within a routed recess in the door so the pad face is flush with or set back slightly from the door surface. From a distance, the device appears to be part of the door panel rather than hardware mounted to it.

Why the Recessed Design Exists

The recessed design solves a specific problem in high-traffic environments where equipment regularly passes through doorways: medical facilities with gurney traffic, emergency departments with IV pole carts, warehouses with pallet jacks. On these doors, a projecting push pad takes repeated equipment impact that bends the pad, loosens the mechanism case, and damages the door itself over time. The INPACT's recessed pad eliminates the protrusion that equipment contacts, extending the device's service life dramatically on impact-prone doors.

94 vs 95 Series

The 94 Series has a grooved push pad surface. The 95 Series has a smooth push pad surface. Both are mechanically and dimensionally identical. All internal parts are shared between 94 and 95. The choice between them is purely aesthetic and is made at specification time based on building design preference. When ordering replacement parts for either series, the part numbers are the same.

INPACT Door Preparation Requirements

The INPACT 94/95 requires a routed recess in the door face for the mechanism case. This prep is built into the door during manufacturing. Steelcraft hollow metal doors are specifically listed as compatible with the standard INPACT door prep. If an INPACT device must be installed on a door that was not prepped at manufacturing, the door must be routed in the field to the INPACT specification, which requires a different site operation than standard exit device installation.

The INPACT trim incompatibility with other Von Duprin series: The 94/95 INPACT Series uses its own dedicated trim line (940 trim, 550 trim, 376 trim). Standard 98/99 trim, 33A trim, or 78 Series trim will not fit the INPACT because the trim-to-mechanism interface is different due to the recessed installation geometry. When ordering replacement trim for an INPACT installation, always confirm the device is a 94/95 Series and order from the INPACT-compatible trim list, not from the standard Von Duprin trim catalog.

INPACT Electronic Options

The INPACT 94/95 Series supports Quiet Electric Latch Retraction (QEL) and field-reversible handing. The QEL option makes the INPACT particularly well-suited to healthcare corridor applications where both impact protection (recessed pad) and quiet electric latch operation are specified simultaneously. These two features together address the two most common exit device complaints in healthcare: equipment impact damage and latch noise in patient care areas.

Von Duprin 54 Series Mullions: Parts and Critical Security Considerations

A mullion is a vertical structural member that mounts between the two leaves of a double-door opening to provide a fixed strike-receiving element for rim exit devices. Without a mullion on a double-door opening, a rim exit device has no fixed jamb to mount a strike to. The rim latch would have no receptacle, and the door pair could not latch.

Why Mullions Matter for Fire Door Code Compliance

On fire-rated double-door openings, the code governing whether a rim exit device is permitted or a concealed vertical rod device is required turns on whether a mullion is present. A rim exit device on a fire-rated pair without a mullion is a non-compliant installation: the rim strike mounts to the active door leaf, which is not a fixed structure and cannot provide the fire-resistive separation required by the door assembly listing. With a fixed or removable mullion providing a fixed strike location, rim exit devices are permitted on most fire-rated pairs. Without a mullion, concealed vertical rod devices are required.

54 Series Mullion Types

Model	Material	Type	Key Notes
5654	Aluminum	Fixed surface mullion	Standard mullion for most double-door exit device applications. Prepped for two 299 strikes. Ships with 154 mullion stabilizers. 11/16 inch wide on door face, 2-3/8 inch at widest, 3-1/8 inch deep, 1/8 inch wall thickness. Available in 7'2" standard height.
5754	Steel	Fixed surface mullion	Steel version of the 5654. Higher strength for high-abuse applications. Same mounting and strike preps as the 5654.
1654	Steel	Removable mullion	Can be released and retracted to allow full-width double-door passage (deliveries, furniture moves, oversized equipment). Mortise cylinder controls removal on keyed removable versions.
4954	Steel	Removable mullion	Keyed removable steel mullion. Single cylinder operation releases and retracts the mullion. KR54 retrofit kit available to upgrade existing 1654 and 4954 mullions to keyed removable operation without replacing the full mullion.

Mullion Fittings and Covers

The top fitting and cover (part 050135) and the bottom fitting (part 050190) are the end cap assemblies for the 5654 and 5754 mullions. The fitting set (part 050130) includes both top and bottom fittings with all mounting screws. When a mullion fitting is damaged from impact or the fasteners have stripped, the fitting is a separately replaceable component. Always confirm whether the damage is to the fitting only or to the mullion tube body itself before ordering, as these are different parts.

Mullion Stabilizer: The Security Component Nobody Installs

The Von Duprin 154 mullion stabilizer package is included in the box when the 5654 aluminum mullion is purchased. It is the most overlooked component on every mullion installation.

The stabilizer prevents lateral deflection of the mullion under door abuse and impact loading. When a mullion deflects sideways from someone pushing or shaking a door hard, the deflection moves the strike out of alignment with the rim latch on both door leaves simultaneously. This causes both exit devices to release, effectively opening the entire double-door opening without any key, credential, or authorized access event. The 154 stabilizer braces the mullion against the door frame, preventing this deflection and maintaining strike alignment under impact.

The mullion installation that bypasses every access control credential on the opening: A mullion installed without the 154 stabilizer on a secured double-door opening can be defeated by physical abuse: shaking the door pair with sufficient force deflects the unsupported mullion and releases both rim latches. This is not a theoretical vulnerability. It is a documented physical bypass method used in both unauthorized access events and in fire safety investigations of double-door openings. Any mullion installation on a door pair controlling access to a secured area that does not include the 154 stabilizer should be treated as a security deficiency. Installing the stabilizer is a ten-minute operation that closes this bypass.

Weather Stripping for Mullions

The Von Duprin weather stripping (part 050580) is specific to the 5654 and 5754 mullions. Each strip is 10 feet long. Two strips are required per mullion (one on each side of the mullion facing the door leaves). This is an often-omitted component on interior mullion installations but a required component on exterior door applications where the mullion must provide an air and weather seal against the door leaves.

How to Identify the Correct Series and Parts

Five questions determine the correct parts before any order for these series.

1. Is this a pushpad, crossbar, or recessed device? Crossbar spanning the door width = 88 Series (or 55 if narrow stile). Recessed pad flush with door face = 94/95 INPACT. Projecting rectangular pushpad = 75 or 78 Series (or 22, 33A, 98/99 from other series). If in doubt, check the label on the mechanism case.

2. Is the door stile narrow or wide? Narrow stile aluminum storefront = 75 Series (pushpad) or 55 Series (crossbar). Wide stile hollow metal or wood = 78 Series (pushpad) or 88 Series (crossbar). The 88 requires a minimum 4-1/2 inch stile.

3. For mullion parts: is the mullion fixed or removable? A mullion with no visible release mechanism is fixed (5654 or 5754). A mullion with a cylinder or lever release is removable (1654 or 4954). Removable mullions use different fittings from fixed mullions.

4. For 88 Series crossbar parts: is the failure the crossbar tube, the lever arm, or the dogging pin spring? Rattling or dropped crossbar = wedge tite screw loose, no parts needed. Stripped dogging in arm = dogging pin spring first, lever arm assembly only if spring replacement fails. Bent or broken arm body = lever arm assembly replacement (050438 RH or 050439 LH).

5. For INPACT parts: confirm the trim series is 94/95-specific. INPACT trim (940, 550 for INPACT, 376) is not interchangeable with standard Von Duprin trim. Ordering standard trim for an INPACT installation produces parts that physically will not seat in the recessed door prep geometry.

Browse the Von Duprin parts catalog at SecurityParts.com for 75, 78, 88, 94/95 INPACT, and 54 Series mullion components with interactive diagrams. For the full exit device catalog including Falcon exit devices, browse the commercial exit devices catalog. For Von Duprin electric strike parts, browse the electric strikes catalog. Pre-order support is at 845-935-0301 or the contact page.

Why Choose Security Parts for These Von Duprin Parts

Dogging pin spring diagnosis, mullion stabilizer security impact, QEL conversion kit guidance, INPACT trim incompatibility warning, and same-day shipping.

Dogging Pin Spring First

We document the dogging pin spring as the correct first replacement for 88 Series dogging failures, not the lever arm. This single fact prevents most unnecessary lever arm orders on 88 Series dogging complaints.

Mullion Stabilizer Warning

We document the 154 stabilizer as a security-critical component that prevents physical bypass of secured double-door openings via mullion deflection. No other parts supplier makes this explicit at the ordering stage.

QEL Conversion Guidance

We document the QEL modular conversion kit for 70 Series devices sold after October 2014, eliminating the need for full device replacement when only quieter latch retraction is needed.

Same-Day Shipping

Most 75, 78, 88, INPACT, and mullion parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for series identification support.

What Makes Security Parts Different for These Von Duprin Parts

We document the dogging pin spring as the first-check replacement for 88 Series crossbar dogging failures. The spring prevents a $150 lever arm order when only a $5 spring has failed. This is undocumented at all competitor parts suppliers.
We document the mullion stabilizer 154 as a security-critical component that closes a documented physical bypass vulnerability on unsupported mullion installations. No other parts supplier explains what happens without the stabilizer.
We explain the fire door code context: a rim device on a fire-rated pair is only permitted when a mullion is present. Without a mullion, concealed VR devices are required. This code context determines whether a mullion purchase is a preference or a code compliance requirement.
We document the INPACT 94/95 Series trim incompatibility. Standard Von Duprin trim will not fit an INPACT installation. This prevents wrong-trim orders that generate returns and installation delays on healthcare projects.
We carry these Von Duprin parts alongside electric strike parts, exit alarm parts, LCN door closer parts, Schlage cylindrical lock parts, and mortise lock parts for complete building service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

Von Duprin 75, 78, 88, and INPACT exit devices appear on the same doors as electric strikes, door closers, and cylindrical locks. Mullions appear on double-door openings that also typically include one of these exit device series.

For Von Duprin electric strike parts on 75, 78, 88, or INPACT rim device installations with controlled entry, browse the electric strikes catalog. For exit alarm parts including Von Duprin Guard-X and Detex ECL and EAX for secondary exit monitoring, browse the exit alarms catalog. For LCN door closer parts on fire-rated egress doors in the same building, browse the door closers catalog. For Schlage ND and ALX Series cylindrical lock parts on interior doors in the same facility, browse the cylindrical locks catalog. For Falcon 19, 24, and 25 Series exit device parts as an alternative brand on newer construction egress doors in the same building, browse the Falcon hardware catalog.

Browse the complete all products and parts catalog to source Von Duprin, Schlage, LCN, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Von Duprin 75, 78, 88, 94/95 and 54 Series Parts

What is the difference between the Von Duprin 75 and 78 Series exit devices?

Both are pushpad devices in the 70 Series family, sharing the same QEL quiet electric latch option and full configuration range. The 75 is narrow stile for aluminum storefront and narrow frame commercial doors. The 78 is wide stile for standard hollow metal and wood doors. Both support rim, SVR, CVR, and wide door cable configurations and the same electronic options including QEL, RX, and E8875.

What is the Von Duprin 88 Series crossbar and how is it replaced?

The 88 Series crossbar tube (part 967738, shared with 55 Series) is 1 inch in diameter and 42 inches long, field-cut to fit. It is held to the lever arms by the tube attaching ring (090021) and wedge tite screw (88R100). A rattling or dropped crossbar is almost always loose wedge screws, not a failed component. Retighten with blue thread-locker. Full lever arm replacement (050438 RH, 050439 LH) is needed when the dogging screw in the arm is stripped or the arm body is damaged.

What is the dogging pin on the Von Duprin 88 Series and when does it fail?

The dogging pin on the underside of the 88 active lever arm holds the crossbar in the depressed position. Its internal spring wears and fails, preventing the crossbar from staying dogged. The spring is a separately replaceable component, much less expensive than a full lever arm assembly. Always check the dogging pin spring before ordering a lever arm when the 88 Series will not dog.

What is the Von Duprin 94/95 INPACT Series and what makes it different?

The INPACT is a fully recessed exit device where the push pad sits within the door face rather than projecting outward. It eliminates impact damage from carts and equipment in healthcare and high-traffic corridors. The 94 has a grooved pad; the 95 has a smooth pad. Both are mechanically identical. INPACT requires a routed door prep and uses its own dedicated trim (940, 550, 376) that is not interchangeable with standard Von Duprin trim. Supports QEL for quiet electric latch operation.

What is a Von Duprin 54 Series mullion and when is one required?

A mullion is a vertical member between double doors providing a fixed strike for rim exit devices. The 54 Series covers fixed aluminum (5654), fixed steel (5754), and removable steel (1654, 4954) mullions. On fire-rated double-door pairs, a rim exit device can only be used if a mullion is present. Without a mullion, concealed vertical rod devices are required by code.

What is the Von Duprin mullion stabilizer and why is it critical?

The 154 mullion stabilizer prevents lateral deflection of the mullion under impact or door abuse. Without the stabilizer, the mullion can be deflected by physical force, which simultaneously releases the rim latches on both door leaves and bypasses the secured opening without any credential. The 154 is included with the 5654 aluminum mullion and must be installed on every mullion on a security-sensitive double-door opening.

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Von Duprin 22, 33A/35A and 55 Series Exit Device Parts: Complete Replacement Guide Thursday, July 2, 2026

Security Parts carries parts for the Von Duprin 22, 33A/35A, and 55 Series exit devices. The 22 Series is the economy wide stile device for medium-to-low traffic with a 3-13/16 inch minimum stile. The 33A/35A is the narrow stile pushpad device with a fluid dampener, deadlocking latch, and concealed VR configurations for stiles as narrow as 2-1/8 inches. The 55 Series is the traditional crossbar device for aluminum storefront doors with stiles as narrow as 1-3/4 inches. Key shared parts: the dogging shaft and adapter work across 22, 33A, 98, and 99 Series. The 33A/35A ALK alarm kit is compatible with 22, 33A, 35A, 98, and 99 Series. The 55 Series uses dedicated narrow stile trim that is not interchangeable with any other Von Duprin series.

Von Duprin invented the first self-releasing fire exit device over a century ago. The 22, 33A/35A, and 55 Series represent three distinct product lines that together cover the majority of commercial egress doors installed in North America from the 1970s through today. When one of these devices needs a replacement part, the most critical first step is confirming which series is installed. Parts from the 33A/35A will not work on the 22. Parts from the 55 will not work on either. Trim from the 98/99 will not fit the 55. Getting the series wrong generates a return.

Browse the complete Von Duprin parts catalog at SecurityParts.com for 22, 33A/35A, 55, and all other Von Duprin series with interactive diagrams. For the full exit device catalog including Falcon exit devices alongside Von Duprin, browse the commercial exit device parts catalog.

Grade 1 ANSI A156.3 certification on all three Von Duprin series

1-3/4" Minimum door stile width on 33A/35A concealed VR and 55 Series

1998 Year the current dogging shaft design went into production for 22/33A/98/99 Series

2002 Year 33/35 Series was discontinued; replaced by 33A/35A with new parts

Three Series, Three Applications: How to Choose and Why It Matters for Parts

Von Duprin 22 Series

Economy | Wide Stile | Medium-Low Traffic

Modern touch bar styling for medium to low traffic openings. 3-13/16 inch minimum stile. Rim (22) and surface VR (2227) only. No concealed VR version. Compatible with 22-ALK alarm kit and limited trim options. Covers 161 door prep. UL listed for panic and fire (22-F). Made in USA. Best for clinic/healthcare back doors, multi-family entries, retail secondary exits.

Von Duprin 33A/35A Series

High Performance | Narrow Stile | Full Configuration Range

Deadlocking latch, fluid dampener, pushpad design. 1-3/4 inch minimum stile. Rim (33A/35A), surface VR (3327A/3527A), concealed VR (3347A/3547A, stile to 3-1/2 inch), and narrow concealed VR (3348A/3548A, stile to 2-1/8 inch). Full electrified option range. 33A has grooved case; 35A has smooth case. Both mechanically identical. Not compatible with older 33/35 pre-2002 parts.

Von Duprin 55 Series

Traditional Crossbar | Narrow Stile | Aluminum Storefront

Classic crossbar design for aluminum framed glass storefront and narrow stile doors. 1-3/4 inch minimum stile. Rim (55) and concealed VR (5547). Handed device: specify LHR or RHR when ordering. Uses dedicated 55 Series trim: 550DT, 555NL, 379L. Standard 98/99 or 33A trim does not fit. Production since at least the 1970s. Historic aesthetic, maximum activation zone, visual transparency due to no bulky mechanism case.

Von Duprin 22 Series Parts

The 22 Series is the value-line option in the Von Duprin exit device catalog. It is not a light-duty device: it carries the same ANSI A156.3 Grade 1 certification as the 33A/35A and 98/99 Series and is UL listed for both panic and fire hardware. What distinguishes it from the 33A/35A is the absence of a fluid dampener and deadlocking latch, a narrower trim compatibility range, and no concealed VR configuration. For doors where these features are not required, the 22 Series provides genuine Von Duprin Grade 1 quality at a more economical price point.

22 Series Center Case

The center case is the core mechanism housing that contains the latch bolt and push bar actuating mechanism. The 22 rim device center case and the 2227 surface vertical rod center case are different parts and not interchangeable. The 2227 (SVR version) has a separate center case because it must accommodate the rod actuating mechanism in addition to the latch bolt. When ordering a replacement center case, always confirm whether the installed device is a 22 rim (single latch point) or 2227 SVR (two-point latching with top and bottom rods).

22 Series Dogging Cover Plates

The dogging cover plate covers the dogging assembly on the hinge side of the exit device. It is a frequently lost or damaged component. On 3-foot devices, the cover plate part number is 968595 (10-3/4 inches long). On 4-foot devices, the cover plate is 968596 (16-3/4 inches long). These cover plates are device-length specific. Installing a 3-foot cover plate on a 4-foot device leaves the dogging assembly exposed and vulnerable to damage and debris accumulation.

22 Series End Cap and 2227 Rod Guide Assembly

The end cap covers the hinge-side end of the mechanism channel. The 22 Series uses the 050014 impact-resistant end cap kit (shared with 33A/35A and 98/99 Series) which replaces all previous end cap versions. This cross-series compatibility is one of the few shared parts between the 22 and 33A/35A families.

The 2227 rod guide assembly 112063 replaces the older style SVR rod guide that used a plastic cap and springs. The new rod guide adds strength and rigidity to the top and bottom rods on the surface VR version. If the rods on a 2227 installation show visible flex or misalignment during operation, the rod guide assembly is the correct replacement.

22 Series Trim and Cylinder Compatibility

The 22 Series uses the 230L lever trim (works on both 22 rim and 2227 SVR) and the 210L knob trim. The trim-to-device interface on the 22 Series uses a tailpiece guide (part 22-ALK, 33A-ALK, 35A-ALK, 98-ALK, and 99-ALK are all the same tailpiece guide) that guides the rim cylinder tailpiece into the back of the exit device. This part is shared between the 22, 33A, 98, and 99 Series.

The shear pin that technicians rarely know exists: Von Duprin lever trims on the 230L, 360L, 992L, 994L, and 996L use a shear pin (3/16 inch diameter, 5/8 inch overall length, with retaining ring) that is designed to snap if the lever handle is forced. This is an intentional sacrificial component: when someone forces a lever trim, the shear pin breaks rather than allowing the mechanism case, trim escutcheon, or through bolts to absorb the full impact force. The result is a lever that becomes inoperative after a forced entry attempt while the mechanism case and door hardware remain intact. When a 22 or 33A trim lever becomes loose or detached after a forced entry event, check the shear pin before ordering any other component. Replacing only the shear pin (part number 050156, includes retaining ring) restores the lever without any other replacement.

Von Duprin 33A/35A Series Parts

The 33A/35A Series is Von Duprin's highest-performing push pad exit device for narrow stile applications. The fluid dampener, deadlocking latch, and full concealed VR configuration range set it apart from both the 22 Series and the 55 Series for any application requiring high performance on a narrow stile door. Understanding the parts requires knowing which configuration is installed, because center cases, cover plates, and rod assemblies differ across rim, surface VR, and concealed VR versions.

33A vs 35A: The Case Style Distinction

The 33A has a grooved (ribbed) mechanism case exterior. The 35A has a smooth mechanism case exterior. Both are mechanically and dimensionally identical in every other respect. All internal parts, including the center case assembly, dogging shaft, end cap, latch bolt, and fluid dampener, are the same between 33A and 35A. When ordering parts for a 33A/35A device, the case style (grooved vs smooth) does not affect internal part numbers. It only affects the external center case cover, which is a cosmetic and protective component that is series-specific but not interchangeable between grooved and smooth styles.

Fluid Dampener: The Noise-Reduction Component

Every 33A/35A exit device is equipped with a fluid dampener that decelerates the push pad on its return stroke after being pressed. This is the feature that makes the 33A/35A appropriate for quiet-operation environments: healthcare corridors, educational facilities, and any space where the metal-on-metal snap-back of an un-dampened push pad would be a noise disturbance.

The fluid dampener is part of the mechanism case assembly. It cannot be replaced as a standalone field component: the dampener is integrated into the center case during manufacturing. If the dampener fails (indicated by loud snap-back noise on push pad return that was not previously present), the center case assembly replacement is the correct service action.

The quiet door that suddenly starts slamming its push pad: A 33A/35A installation that has been quiet for years and suddenly produces loud push pad snap-back noise has almost certainly experienced a fluid dampener failure. This happens either from mechanism wear over extended high-cycle use or from an impact event that compresses the dampener beyond its design range. It is not a lubrication issue and it is not corrected by adjusting spring tension. The center case assembly replacement restores the quiet operation. On healthcare projects where noise compliance is a facility management metric, documenting this distinction prevents unnecessary maintenance calls for other potential causes.

33A/35A Concealed Vertical Rod Configurations

The 33A/35A Series offers two concealed vertical rod configurations for different stile width situations.

3347A/3547A (concealed VR, 3-1/2 inch minimum stile): Used on hollow metal single and double doors where the stile is 3-1/2 inches or wider. The concealed rods run inside the door stile with no visible rod hardware on the door face. The top latch (part 050494) is used on both 33A, 35A, 98, and 99 concealed VR devices. This cross-series compatibility on the concealed top latch is one of the few cases where 33A/35A and 98/99 parts overlap on CVR configurations.

3348A/3548A (narrow concealed VR, 2-1/8 inch minimum stile): Used on hollow metal doors with stiles as narrow as 2-1/8 inches. This is the narrowest concealed VR configuration in the Von Duprin line and is specified on doors that cannot accommodate the 3347A minimum stile. Fire-rated versions (3348A-F and 3548A-F) support 8-foot by 10-foot door pairs at UL fire listing.

Configuration	Model	Min Stile	Latching	Notes
Rim	33A / 35A	1-3/4 inch	Single point rim latch	Non-handed except with SS option
Surface VR	3327A / 3527A	3-5/8 inch	Two-point: top latch + bottom rod	Non-handed except with SS option
Concealed VR (wide)	3347A / 3547A	3-1/2 inch	Two-point concealed rods in stile	5/8 inch throw. Non-handed except SS
Concealed VR (narrow)	3348A / 3548A	2-1/8 inch	Two-point concealed rods in stile	5/8 inch top, 1-1/2 inch bottom throw. Non-handed except SS
Concealed VR cable	49A	Less specific	Two-point concealed vertical cable	Available less bottom latch (LBL)

33A/35A and 22 Series Shared Dogging Shaft

The dogging shaft and dogging adapter that have been in production since 1998 are shared across the Von Duprin 22, 33, 33A, 98, and 99 Series devices. This is confirmed by the official Von Duprin parts catalog. The dogging shaft is the current standard replacement for any of these series when dogging function fails. The hex key dog conversion kit (parts 050114 and 050117) converts 33A and 99 Series hex key dogging to cylinder dogging, allowing a standard mortise cylinder to control dogging without carrying a hex key. The conversion kit does not include the cylinder.

33A/35A Alarm Kit (ALK)

The ALK alarm kit converts a 22, 33A, 35A, 98, or 99 Series exit device to an alarmed device. When the push bar is pressed, a 100dB battery-powered alarm sounds. The kit is powered by a standard 9-volt battery and controlled by a mortise cylinder (not included). The kit includes the EMERGENCY EXIT ONLY. ALARM WILL SOUND decal. An ALK power supply is available for hardwired operation of one or two alarm kits from a single 12V or 24V power source. Browse the exit alarm parts catalog at SecurityParts.com for ALK kits and Detex and Von Duprin Guard-X alarm components.

Von Duprin 55 Series Parts: The Crossbar Legacy Line

The Von Duprin 55 Series has been in production since at least the 1970s. It is the traditional crossbar exit device: instead of a push pad, it uses a suspended metal crossbar that spans nearly the full door width and activates the latch mechanism when any part of the bar is pressed. This design predates the push pad era and remains in production because it serves two applications that the pushpad cannot match: it is the only Grade 1 Von Duprin device for storefront aluminum doors with stiles at the absolute minimum of 1-3/4 inches, and it is the correct retrofit device for historic and mid-century buildings where maintaining the crossbar aesthetic is an architectural requirement.

55 Series Center Case (Part 050183)

The 55 Series center case (part 050183) is the core replacement housing for the 55 rim device. It includes all internal workings and the latch bolt. The center case geometry on the 55 Series is completely different from the 22, 33A, or 98/99 Series. Center cases are not cross-compatible. When ordering a replacement 55 Series center case, confirm the device is a 55 rim (single latch point) rather than the 5547 concealed VR, as these are different assemblies.

55 Series Lever Arm and Hinge Case Axle

The 55 Series uses a lever arm mechanism that connects the crossbar to the center case and activates the latch when the crossbar is pressed. The lever arms are handed: right hand (050355) and left hand (050356). Always confirm the device handing before ordering a lever arm.

The center case axle (090050) is used on the 55 rim device. The hinge case axle (090051) is used on the inactive housing (hinge side) and on all other 55 configurations including the 5547 CVR device. The arm bushing (050333) takes up the mechanical slack between the lever arms and the housing; it is a wear component that should be checked when lever arm movement feels loose or imprecise.

The 55 Series sagging crossbar fix that prevents most 55 Series callbacks: The most common service complaint on the 55 Series is a sagging crossbar after installation. This happens when the wedge screws in the lever arm are not fully tightened during installation. The crossbar drops at one or both ends under its own weight, which can prevent full latch retraction at the extremes of the push bar. The fix is straightforward: tighten the wedge screws in both lever arms while holding the crossbar at the correct height. This is not a parts failure. No replacement parts are needed. The sagging crossbar is almost always an installation torque issue, not a worn or broken component.

55 Series Trim: Dedicated and Non-Interchangeable

The 55 Series uses narrow stile-specific outside trim that is not compatible with any other Von Duprin series. The three standard trim options are 550DT (dummy pull, non-functional outside handle), 555NL (night latch with outside cylinder that locks and unlocks the push bar), and 379L (outside lever trim). Standard Von Duprin 360L, 230L, or 99/98 Series trim will not fit the 55 Series because the mechanism case geometry is different.

When a 55 Series installation needs outside trim replacement, always order from the 55-specific trim range. When a building has a mix of 55 Series and 98/99 or 33A devices, the trim from one series cannot be used on the other even if the finish matches.

5547 Concealed Vertical Rod: The 55 Series Double-Door Solution

The 5547 is the concealed vertical rod version of the 55 Series, used on double-door aluminum storefront configurations where both doors need the crossbar aesthetic with concealed rod latching. The 5547 blind fastener kit (900539) connects the rod control housing to the rods and is specific to the 5547 CVR only. The 5547 uses the hinge case axle (090051) as does all 55 Series hardware except the 55 rim center case.

Parts Cross-Compatibility: What Works Across Series and What Does Not

The most expensive parts ordering mistakes on Von Duprin exit devices happen at the series boundary. Some parts cross series; most do not.

Part	22	33A/35A	55	98/99
Current dogging shaft (post-1998)	Yes	Yes	No	Yes
Impact-resistant end cap kit 050014	Yes	Yes	No	Yes
Tailpiece guide (ALK suffix)	Yes	Yes	No	Yes
ALK alarm kit	Yes	Yes	No	Yes
Concealed top latch 050494	No	Yes (CVR)	No	Yes (CVR)
230L lever trim	Yes	No	No	No
Shear pin 050156	Yes (230L/360L/992L)	Yes (same trims)	No	Yes (same trims)
Center case assembly	22 only	33A/35A only	55 only	98/99 only
Latch bolt	22 only	33A/35A only	55 only	98/99 only

33A/35A parts are NOT compatible with the pre-2002 33/35 Series: The 33A/35A was introduced in 2002 as a redesigned replacement for the older 33/35 Series. The two series look similar but use different internal components. Most 33A/35A parts will not work on an older 33/35 device. Identify the generation by the center case cover design: 33A/35A (current) has a one-piece center case cover; the older 33/35 has a two-piece cover. For older 33/35 devices, contact Security Parts at 845-935-0301 for compatible parts identification before ordering.

How to Identify the Correct Series Before Ordering

The series identification that prevents a wrong-part return takes under 30 seconds on any Von Duprin installation.

Is there a push pad or a crossbar? A crossbar spanning most of the door width = 55 Series. A push pad (compact rectangular bar) = 22, 33A, 35A, 98, or 99 Series. Go to the next check.

Is the door stile wide (4 inches or more) or narrow (under 4 inches)? Wide stile hollow metal doors most often have 98/99 or 22 Series. Narrow stile aluminum storefront doors most often have 33A/35A or 55 Series. The device label on the mechanism case confirms the exact series.

Check the mechanism case label. The series number is on a label on the center case. This is the definitive identification. On the 33A, the case exterior has visible ribs (grooved). On the 35A, the case is smooth. Both are current generation if the center case cover is one piece. Older 33/35 Series (pre-2002) have a two-piece center case cover.

Browse the Von Duprin parts catalog at SecurityParts.com with interactive diagrams for all series. For Von Duprin electric strike parts compatible with 22 and 33A/35A rim exit devices, browse the electric strikes catalog. For Von Duprin Guard-X exit alarm parts, browse the exit alarms catalog. For the full Falcon exit device catalog as an alternative brand, browse the Falcon hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose Security Parts for Von Duprin 22, 33A/35A and 55 Series Parts

Series cross-compatibility table, 33/35A vs 33/35 generation warning, shear pin documentation, fluid dampener failure diagnosis, and same-day shipping on stocked parts.

Cross-Compatibility Table

We document which parts work across 22, 33A/35A, 55, and 98/99 Series. The dogging shaft and end cap are cross-series. Center cases and latch bolts are not. This table eliminates the most common wrong-series order.

Generation Warning

We document that 33A/35A parts are not compatible with pre-2002 33/35 Series devices and how to identify the generation from the center case cover. No other parts supplier explains this before the order is placed.

Shear Pin and Dampener

We document the shear pin as the first-check component after any forced entry on a 230L or 360L lever trim, and the fluid dampener as the cause of sudden push pad snap-back noise on 33A/35A devices.

Same-Day Shipping

Most 22, 33A/35A, and 55 Series parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for series identification support.

What Makes Security Parts Different for These Von Duprin Parts

We document the parts cross-compatibility table showing which parts work across 22, 33A/35A, and 98/99 Series (dogging shaft, end cap, tailpiece guide, ALK) versus which are series-exclusive (center case, latch bolt, trim). No parts supplier makes this available at the ordering stage.
We document the 33/35 vs 33A/35A generation boundary with the one-piece vs two-piece cover identification method. The 2002 redesign created a complete parts break that generates returns on any order where the generation is not confirmed first.
We document the shear pin (050156) as the sacrificial component in 230L, 360L, 992L, 994L, and 996L lever trims. Most technicians who encounter a loose lever after a forced entry event replace the trim assembly when only the shear pin has failed.
We document the 55 Series sagging crossbar as an installation torque issue on the wedge screws, not a parts failure. This eliminates unnecessary service calls and parts orders on new 55 installations.
We carry a wide range of parts, including Von Duprin, electric strike, exit alarm, LCN door closer, Schlage cylindrical lock, and mortise lock parts, providing comprehensive building hardware service in a single order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at SecurityParts.com

Von Duprin 22, 33A/35A, and 55 Series exit devices typically appear on egress doors alongside electric strikes for controlled entry and LCN door closers for self-closing operation on fire-rated assemblies.

For Von Duprin 5100, 6100, 6200, and 6300 electric strike parts compatible with 22, 33A/35A, and 55 Series rim devices, browse the electric strikes catalog. For Von Duprin Guard-X and Detex ECL and EAX exit alarm parts, browse the exit alarms catalog. For LCN door closer parts on fire-rated egress doors in the same building, browse the door closers catalog. For Schlage ND and ALX Series cylindrical lock parts on interior doors in the same facility, browse the cylindrical locks catalog. For Falcon 19, 24, and 25 Series exit device parts as an alternative brand on newer or renovation egress doors in the same building, browse the Falcon hardware catalog.

Browse the complete all products and parts catalog to source Von Duprin, Schlage, LCN, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Von Duprin

22, 33A/35A and 55 Series Exit Device Parts

What is the difference between the Von Duprin 22 and 33A/35A Series exit devices?

The 22 Series is the economy option with modern touch bar styling, a 3-13/16 inch minimum stile, and rim and surface VR configurations only. The 33A/35A is the higher-performance narrow stile device with a deadlocking latch, fluid dampener for quiet operation, stiles as narrow as 1-3/4 inch, and a full configuration range including rim, surface VR, and concealed VR. The 33A has a grooved case; the 35A has a smooth case. Both are mechanically identical.

What is the Von Duprin 55 Series and when should it be specified instead of the 33A/35A?

The 55 Series is a traditional crossbar exit device for aluminum storefront and glass doors with stiles as narrow as 1-3/4 inch. It should be specified over the 33A/35A when retrofitting doors with existing crossbar hardware, when maintaining a historic or retro architectural aesthetic is required, or when maximum push bar activation area is needed. The 55 Series uses dedicated narrow stile trim (550DT, 555NL, 379L) that is not interchangeable with any other Von Duprin series trim.

What is the dogging shaft on Von Duprin exit devices and when does it need replacement?

The dogging shaft locks the push bar in the depressed position for free-swing operation during business hours. The current shaft design for 22, 33, 33A, 98, and 99 Series has been in production since 1998. Replace when it is difficult to turn, no longer holds the push bar dogged, or is physically bent. A hex key to cylinder dogging conversion kit (050114 and 050117) is also available for 33A and 99 Series to allow mortise cylinder control.

What is the 33A/35A fluid dampener and why does it matter?

The fluid dampener decelerates the push pad on its return stroke to reduce the snap-back noise associated with standard exit devices. It is integrated into the mechanism case and cannot be replaced as a standalone component. If a 33A/35A device begins producing loud push pad snap-back noise that was not previously present, the center case assembly replacement restores quiet operation. Lubrication and spring adjustment do not resolve a failed dampener.

Will Von Duprin 33A/35A Series parts work on older 33/35 Series devices?

No. The 33A/35A redesign in 2002 created a parts break with the older 33/35 Series. Most current parts are not compatible with pre-2002 devices. Identify the generation by the center case cover: one-piece cover = current 33A/35A. Two-piece cover = older 33/35. Contact SecurityParts.com for compatible parts identification on older devices before ordering.

What is the Von Duprin ALK alarm kit and which series does it work with?

The ALK alarm kit adds a 100dB battery-powered alarm to an existing exit device that sounds when the push bar is pressed. It is compatible with Von Duprin 22, 33A, 35A, 98, and 99 Series devices. It runs on a 9-volt battery and is controlled by a mortise cylinder (not included). The ALK does not work on the 55 Series. A hardwired ALK power supply is available for connecting one or two alarm kits to a 12V or 24V power source.

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LCN Benchmark and Senior Swing Automatic Door Operator Parts: 9130 9140 9150 and 9500 2800 Series Complete Guide Wednesday, July 1, 2026

Security Parts carries parts for the LCN Benchmark 9130, 9140, and 9150 Series and the Senior Swing 9500 and 2800 Series automatic door operators. The Benchmark is low-to-medium duty with a 200-pound door capacity. The Senior Swing is the heaviest-duty version, rated for doors up to 600 pounds. The 9500IQ and 2800IQ Senior Swing generation adds AdaptivIQ self-calibrating technology that eliminates seasonal manual adjustments. Both lines use Push N Go non-switch activation that triggers when a person manually opens the door to 5 degrees. During power failure, both act as manual closers and do not block egress. All three Benchmark models use the same installation manual (740158). The 9500 is surface mounted; the 2800 is overhead concealed.

LCN automatic door operators are on more commercial entrances, healthcare corridors, and accessibility-required openings in North America than any other low-energy electromechanical operator brand. The Benchmark and Senior Swing lines cover the full range from budget-conscious retrofits through high-abuse institutional applications. When one fails or needs a component replacement, identifying the correct series, mounting configuration, and generation is the only way to order the right part without a return.

Browse the complete LCN parts catalog at SecurityParts.com, covering all LCN automatic operator and door closer product lines. For the full range of LCN door closer and automatic operator parts including the 4040XP, 4000 Series, Benchmark, and Senior Swing, browse the commercial door closer parts catalog.

200 lbs Maximum door weight for LCN Benchmark 9130/9140/9150 Series

600 lbs Maximum door weight for LCN Senior Swing 9500/2800 Series

5 degrees Door angle that triggers Push N Go automatic takeover on both series

1-30 sec Adjustable hold-open time delay on both Benchmark and Senior Swing

What LCN Automatic Door Operators Do and Why They Exist

LCN automatic door operators are low-energy electromechanical swing door operators. They are distinct from full-power high-energy automatic door systems (the kind that open from a distance without any manual contact) and distinct from manual door closers (the hydraulic units that simply return a door to the closed position).

The specific application a low-energy operator fills is a door that is primarily intended for automatic use by people who cannot easily open a manual door, combined with the ability to be pushed open manually by regular pedestrian traffic. This two-in-one capability is what the ADA requires for accessible entrances where not every user needs automatic operation but where those who do cannot be expected to push a button or operate a separate actuator every time.

The code standard that governs these operators is ANSI/BHMA A156.19 (Power Assist and Low Energy Power Operated Doors). Both the Benchmark and Senior Swing series are certified to A156.19 and to ANSI A117.1 (Accessible and Usable Buildings and Facilities). UL listing is standard on both series.

The ADA requirement that drives operator specification: ADA Section 4.13.12 and the 2010 ADA Standards for Accessible Design require that doors on accessible routes be openable with no more than 5 pounds of force (interior) or 8.5 pounds (exterior). Most standard commercial doors with door closers require 7 to 15 pounds of force to open, which is non-compliant on accessible routes. Installing a low-energy operator on a closer-equipped door effectively eliminates the force required to open the door (the operator opens it), satisfying ADA force requirements without removing the door closer. This is why LCN automatic operators are so frequently found on accessible routes alongside standard door closers: the operator opens, the closer returns, and no single-handed force above the ADA limit is required from the user.

LCN Benchmark Series 9130 9140 9150: What Each Number Means

9130 Series

Pull Side | Surface Mount | Single Door

Surface mounted on the pull side of a single door. Uses a single lever track arm that connects the operator to the door. Best for inswing doors where the operator mounts on the side you pull toward you. 115VAC, 200-pound door capacity. Minimum door width: 30 inches for pull operators. ANSI/BHMA A156.19, ADA compliant, UL listed. 2-year limited warranty.

9140 Series

Push Side | Surface Mount | Single Door

Surface mounted on the push side of a single door. Uses a double-lever arm configuration for push-side mounting. Best for outswing doors where the operator mounts on the side you push away from you. 115VAC, 200-pound door capacity. Minimum door width: 26 inches for push operators. Same code certifications as 9130.

9150 Series

Top Jamb | Surface Mount | Double Door

Surface mounted on the top jamb of the push side for independent or simultaneous pair door applications. The double-door version of the Benchmark line. Each door in a pair typically has its own 9150 operator. Used where both doors in a pair must operate automatically for accessible passage. Same power and weight ratings as 9130 and 9140.

All three Benchmark models share installation manual number 740158. If a technician has the manual for any one of the three models, it covers all three. The gear box part numbers in the LCN parts manual are series-specific, but the installation procedure is shared across the Benchmark family.

How the Benchmark 9130 9140 9150 Work: Key Features

Push N Go Non-Switch Activation

Push N Go is the feature that makes LCN Benchmark operators function without a separate wall-mounted push button for every passage. When a user manually pushes or pulls the door to approximately 5 degrees of opening angle, the operator's internal sensor detects the movement and the operator takes over, continuing to open the door fully and automatically.

After reaching full open, the door holds open for 1 to 30 seconds depending on the time delay adjustment, then closes automatically under spring force. The Push N Go feature means the door behaves exactly like a manual door for regular traffic (anyone can push it open normally) but automatically assists as soon as manual movement is detected, making it accessible without requiring button actuation from anyone in the traffic stream.

Power Boost Wind Compensation

The Benchmark includes a Power Boost function that provides additional closing force when the door is fighting wind resistance during the closing cycle. On exterior doors exposed to prevailing winds, a door closer set for normal closing speed may not fully close and latch the door during windy conditions. Power Boost detects when the closing cycle is being impeded and adds motor-driven closing force to ensure the door fully latches on every cycle. This is a passive feature that operates automatically without any adjustment.

Obstruction Reversal Safety

If the door contacts an obstruction during the closing cycle before reaching the latch position, the operator reverses direction and re-opens the door. This is a required safety function under ANSI/BHMA A156.19 for low-energy power-operated doors. The obstruction reversal prevents the door from closing on a person or wheelchair during the automatic closing sequence.

Power Failure Manual Operation

When power is lost, the Benchmark operator allows the door to be operated manually as a standard door. The operator does not lock the door or prevent movement during a power failure. This is a non-negotiable life safety requirement for any automatic door operator on a means of egress: power failure cannot result in a blocked exit.

LCN Senior Swing 9500 and 2800 Series: The Heavy-Duty Line

The Senior Swing is LCN's highest-duty automatic door operator line. Where the Benchmark is designed for low-to-medium traffic doors up to 200 pounds, the Senior Swing is built for high-abuse, high-traffic commercial applications with doors up to 600 pounds. Healthcare main entrances, hospital corridor fire doors, school main entries, and heavy hollow metal exterior doors in institutional applications are the typical Senior Swing specification environments.

Senior Swing Mounting Configurations

Model	Mount	Door	Configuration
9530	Surface	Single	Pull side, offset arm
9540	Surface	Single	Push side, offset arm
9550	Surface	Simultaneous pair	Both doors open together on single activation
9560	Surface	Independent pair	Each door opens independently, activation triggers one at a time
2810	Overhead concealed	Single	Mechanism inside door header, arm visible on door face
2850	Overhead concealed	Simultaneous pair	Concealed mechanism, simultaneous double door operation
2860	Overhead concealed	Independent pair	Concealed mechanism, independent double door operation

9500IQ and 2800IQ: The AdaptivIQ Generation

The current IQ generation of the Senior Swing adds AdaptivIQ self-calibrating technology. This is the most significant engineering advancement in LCN automatic door operator design in recent years and it addresses the most common complaint facilities managers have about automatic door operators in any brand: seasonal adjustment calls.

External conditions that affect an automatic door operator's performance change throughout the year. Wind pressure changes by season and weather event. HVAC stack pressure (the pressure differential between inside and outside created by building HVAC systems) reverses direction between summer and winter in most commercial buildings, which directly affects how hard the door operator must work to close against or with the pressure. Carpet compression, weather stripping condition, and door weight all vary. On conventional operators, each of these changes may require a field visit to adjust closing speed, hold-open time, or sensitivity settings.

AdaptivIQ continuously monitors door performance and adjusts operator parameters automatically to maintain consistent operation despite these changing external conditions. The result is fewer seasonal adjustment calls, more consistent operation across all weather conditions, and reduced total service cost over the operator's life cycle.

The HVAC stack pressure problem that causes most seasonal Senior Swing adjustment calls: HVAC stack pressure (also called stack effect) reverses polarity between summer and winter in multi-story buildings. In winter, warm air inside rises and exits through upper floors, creating negative pressure at lower-floor entrances that pulls exterior doors inward. In summer, the reverse occurs. On a standard Senior Swing operator without AdaptivIQ, a closing speed setting that is correct in summer may result in the door failing to close completely in winter because the increased inward-pulling pressure is fighting the closing cycle. Seasonal adjustment calls to readjust closing speed are the most frequent preventable service call on Senior Swing installations without IQ technology. AdaptivIQ detects the changed pressure and adjusts the closing force automatically, eliminating this call entirely.

Senior Swing Power Failure Mode

Like the Benchmark, the Senior Swing acts as a manual door closer during a power failure. The LCN documentation specifically states it acts as a size 3 manual door closer when power is lost. The activating circuit opens the door from any position in the closing swing, meaning a partially closed door can still be manually opened during a power failure. This fail-safe design is required for egress compliance on any door on a means of egress.

Access Control Integration: The 1-Second Delay Feature

The Senior Swing includes a 1-second time delay between the activation signal from an access control system and the door beginning to open. This delay is a designed feature, not a malfunction. Its purpose is to allow enough time for an electrically controlled latch or electric strike to fully disengage before the operator begins pulling the door open. Without this delay, the operator would attempt to force the door open before the electric lock has released, either damaging the lock mechanism or failing to open the door completely.

This integration delay is one of the most frequently misdiagnosed behaviors on Senior Swing installations. When a facility first integrates an access control credential reader with a Senior Swing operator, the 1-second gap between credential read and door movement is sometimes reported as an operator malfunction by staff who expect immediate opening. The behavior is correct and intentional. Browse electric strike parts at SecurityParts.com for Von Duprin and Schlage electric strike components compatible with Senior Swing integrated openings.

Benchmark vs Senior Swing: Choosing the Right Operator

Factor	Benchmark 9130/9140/9150	Senior Swing 9500/2800
Door weight capacity	200 lbs maximum	600 lbs maximum
Traffic level	Low to medium traffic	High traffic, high abuse
Mounting	Surface only	Surface (9500) or overhead concealed (2800)
Self-adjusting technology	No (manual adjustments required)	AdaptivIQ on IQ generation (self-calibrating)
Seasonal adjustment calls	Yes, typical on exterior doors	Minimal with IQ generation
Power failure mode	Manual door operation	Size 3 manual closer
Push N Go	Yes, 5-degree trigger	Yes, 5-degree trigger
Power Boost	Yes	Yes
Access control delay	Standard activation	1-second built-in delay for electric lock coordination
Best application	Interior accessible corridors, light exterior retrofit	Main building entries, healthcare, institutional high-use doors
Warranty	2-year limited	2-year limited

What Fails First on LCN Automatic Operators

Field service experience across Benchmark and Senior Swing installations reveals a consistent failure sequence. Knowing this before diagnosing saves time by directing attention to the most likely cause first.

1. Arm Assembly

The arm is the mechanical linkage between the operator unit and the door. It takes direct physical punishment every time the door opens and closes, including impact from carts, gurneys, wheelchair footrests, and manual push force. Bent, cracked, or loose arm assemblies are the most common physical failure on both Benchmark and Senior Swing operators. The arm type (single lever track for 9130, double lever for 9140, offset arm for Senior Swing) must be confirmed before ordering a replacement, as arms are configuration-specific.

For the Benchmark, the arm is a single replaceable component. For the Senior Swing, the arm assembly includes the arm, header plate, and connecting hardware. Always confirm the handing (right hand or left hand) and the mounting configuration (push or pull side) when ordering any arm assembly.

2. Gear Box Assembly

The gear box is the electromechanical drive mechanism that converts motor rotation into door movement. Gear box failure presents as a door that does not open when activated (motor runs but door does not move), a door that opens slowly and incompletely (stripped gears), or grinding noise during operation (gear wear). The gear box is a complete replacement assembly on both Benchmark and Senior Swing.

The LCN parts manual lists gear box assemblies by series number. Part numbers in the manual are 9130-3462SC (9130 Series gear box), 9140-3462SC (9140 Series gear box), and 9150-3462SC (9150 Series gear box). For Senior Swing, gear box part numbers are series-specific and documented in the separate Senior Swing parts section of the LCN Parts Manual. Always have the exact model number (including the series number and any suffix letters from the operator label) before ordering any gear box.

3. Control Board

The electronic control board manages all operator timing: hold-open delay, opening speed, closing speed, obstruction reversal, Push N Go sensing, and Power Boost. Control board failure presents as erratic behavior (door opens inconsistently, holds open indefinitely, or refuses to activate) after all mechanical components and power supply have been confirmed functional.

Before diagnosing a control board failure, confirm the power supply is correct (115VAC, single phase, 60Hz, fused at 15 amps), the arm is correctly connected, and the settings have not been inadvertently reset. A control board that has been reset to factory defaults by a power interruption may appear to have failed when it is actually operating correctly at its default settings, which differ from the field-adjusted settings that were in place before the power event.

The factory default restore that resolves most Senior Swing erratic behavior complaints: The Senior Swing stores both factory default settings and field adjustment settings in separate memory locations. After any power interruption, if the operator behaves erratically, the first service step is to restore factory defaults from the controller. This takes seconds and confirms whether the issue is a programming problem or a hardware failure. If factory defaults restore normal operation, the field settings were corrupted by the power event and must be re-entered. If factory defaults do not restore normal operation, a hardware component has failed. This two-minute diagnostic step eliminates the most common unnecessary control board replacement on Senior Swing operators.

4. Activator and Push Button Wiring

The wall-mounted push button actuator or access control signal wire is the most overlooked failure point on automatic door operators. A door that does not respond to button activation but opens correctly on Push N Go is almost always an actuator or wiring problem, not an operator failure. Check for loose wiring connections at the operator terminal block before assuming the operator has failed. On exterior installations, weather-related corrosion at the actuator wiring terminals is the single most common cause of button-activation failure that appears as operator failure.

5. Power Supply and Circuit

Both the Benchmark and Senior Swing require 115VAC, single phase, 60Hz power on a fused 15-amp circuit. A tripped circuit breaker is the most common cause of a completely non-responsive operator. Before any component diagnosis, confirm power at the operator terminal block with a voltage meter. The 15-amp circuit requirement is frequently violated in retrofit installations where the operator is connected to an existing circuit without verifying the available amperage. An undersized circuit produces intermittent operation as the circuit trips under the operator's starting current draw.

Adjustments and Settings: What Can Be Set in the Field

Both the Benchmark and Senior Swing support field adjustment of several operational parameters without requiring component replacement.

Hold-open time delay: Adjustable from 1 to 30 seconds on both series. This is the time the door remains fully open before beginning the closing cycle. For accessible routes, a minimum hold-open time that allows a wheelchair user to fully pass through before closing begins is required by ADA. The specific required time depends on the door width and the expected rate of passage for the building's user population.

Opening speed: The speed at which the operator drives the door from closed to full open. ANSI/BHMA A156.19 requires that low-energy operators open the door at a speed that does not create a hazard. An operator set to open too quickly can strike a person on the push side of an inswing door. Correct opening speed setting is a safety adjustment, not a preference adjustment.

Closing speed: The speed at which the door closes from the full open position to the latched position. This setting must balance between closing slowly enough to allow full passage time and closing quickly enough to latch before the next person activates the door.

Back check speed: On the Senior Swing, back check speed controls the door speed as it approaches the full open position, preventing the door from slamming into the stop at full opening. Incorrect back check speed setting causes repeated hard impacts between the door and door stop, which accelerates arm and door wear.

On the Senior Swing IQ generation, all speed and timing settings are stored in the controller's digital memory. Field adjustments replace the previous field settings in memory. The original factory defaults are always retained separately and can be recalled at any time, which is the basis of the factory default restore diagnostic described above.

How to Identify Your LCN Automatic Operator for Parts Ordering

Three pieces of information are needed before any LCN automatic operator parts order.

1. Model number: The model number is on a label on the operator housing. For mechanical products, the month and year of manufacture is also stamped near the packing nut at the base of the pinion where the arm attaches. For automatic operators, the label has the date of manufacture. The model number includes the series (9130, 9140, 9150, 9530, 9540, etc.) and any suffix letters that indicate handing, arm configuration, or generation (IQ suffix for the current AdaptivIQ Senior Swing generation).

2. Handing: Right hand (RH) or left hand (LH). Handing is determined by standing on the pull side of the door and noting which side the hinge is on. Right hand means the hinge is on the right. Left hand means the hinge is on the left. Arm assemblies and some mounting hardware are handing-specific.

3. Component failed: Arm assembly (mechanical linkage), gear box (electromechanical drive), control board (electronic controller), or activator/wiring (push button or access control wiring). The failure symptom determines which component to order. A door that does not move when activated but shows power at the terminal block points to the arm connection or gear box. A door that activates but behaves erratically points to the control board. A door that is completely unresponsive points to the power supply or activator wiring.

Browse the complete LCN parts catalog at SecurityParts.com for all Benchmark and Senior Swing components with series-specific diagrams. For the full LCN door closer and operator range including the 4040XP and 4000 Series surface closers and the 4630/4640 Auto Equalizer operators, browse the commercial door closer parts catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for LCN Automatic Operator Parts

HVAC stack pressure seasonal adjustment explanation, factory default restore diagnostic, access control 1-second delay documentation, and same-day shipping on stocked parts.

Stack Pressure Guidance

We document HVAC stack pressure as the primary driver of seasonal Senior Swing adjustment calls. AdaptivIQ eliminates this. No other parts supplier explains the mechanism behind the most common preventable service call on LCN operators.

Factory Default Restore

We document the factory default restore as the first diagnostic step on erratic Senior Swing behavior. This two-minute step eliminates most unnecessary control board replacement orders.

1-Second Delay Documentation

We document the Senior Swing's built-in 1-second activation delay as an intentional feature for electric lock coordination. Most facilities report this as operator failure on first access control integration.

Same-Day Shipping

Most LCN Benchmark and Senior Swing parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for model and series identification support.

What Makes SecurityParts.com Different for LCN Automatic Operator Parts

We document the HVAC stack pressure reversal between summer and winter as the mechanism behind seasonal closing speed adjustment calls. No other parts supplier or competitor explains why these calls happen or how AdaptivIQ prevents them.
We document the ADA force requirement context: the reason LCN operators exist alongside door closers is that closers create force that exceeds ADA limits on accessible routes. The operator opens, the closer returns, ADA compliance is maintained. No supplier explains this relationship at the parts level.
We document the 1-second activation delay on the Senior Swing as an intentional access control coordination feature. Facilities that don't know this report the operator as broken on the first day after access control integration, generating unnecessary service calls.
We document the factory default restore as a two-minute diagnostic that resolves most erratic behavior without any parts replacement. This one piece of knowledge eliminates the most common unnecessary control board order on Senior Swing operators.
We carry LCN automatic operator parts alongside electric strike parts, exit device parts, cylindrical lock parts, and mortise lock parts for complete door system service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

LCN automatic door operators are part of a complete door system that typically includes an electric strike or magnetic lock for access control, a door closer for fire-rated applications, and sometimes exit device hardware on egress doors. SecurityParts.com stocks all of these for a complete opening service call.

For Von Duprin electric strike parts on automatic operator openings with access control integration, browse the electric strikes catalog. For commercial exit alarm parts on automatic operator doors with alarm monitoring, browse the exit alarms catalog. For Von Duprin and Falcon exit device parts on automatic operator doors that also require panic hardware, browse the exit devices catalog. For Schlage ND Series cylindrical lock parts on adjacent doors in the same building, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on high-security entries in the same facility, browse the mortise locks catalog.

Browse the complete all products and parts catalog to source LCN, Schlage, Von Duprin, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About LCN

Benchmark and Senior Swing Automatic Door Operator Parts

What is the difference between the LCN 9130, 9140, and 9150 Benchmark Series?

The 9130 mounts on the pull side of a single door with a single lever track arm. The 9140 mounts on the push side of a single door with a double-lever arm. The 9150 mounts on the top jamb on the push side for independent or simultaneous double-door pairs. All three handle doors up to 200 pounds, run on 115VAC, share installation manual 740158, and meet ANSI/BHMA A156.19 and ADA requirements.

What is the difference between the LCN Benchmark and Senior Swing automatic door operators?

The Benchmark 9130/9140/9150 is low-to-medium duty with a 200-pound door capacity for primarily automatic applications. The Senior Swing 9500/2800 is the heaviest-duty version rated for doors up to 600 pounds in high-traffic, high-abuse environments. The 9500IQ and 2800IQ Senior Swing generation adds AdaptivIQ self-calibrating technology that eliminates seasonal manual adjustments. The 9500 is surface mounted; the 2800 is overhead concealed.

What is Push N Go activation on the LCN Benchmark and Senior Swing?

Push N Go activates the operator automatically when a person manually opens the door to approximately 5 degrees. The operator takes over from that point, opens the door fully, holds it open for 1 to 30 seconds (adjustable), then closes automatically. No separate button activation is required. The door behaves as a manual door for regular traffic while automatically assisting anyone who begins to push it.

What happens to the LCN Senior Swing and Benchmark operators during a power failure?

Both act as manual door closers during a power failure. The Senior Swing specifically functions as a size 3 manual closer when power is lost. Neither operator locks the door or prevents egress. The door can be manually opened from any position in the closing swing during a power failure, maintaining egress compliance on means-of-egress doors.

What is LCN AdaptivIQ technology on the Senior Swing 9500IQ?

AdaptivIQ is a self-adjusting, self-calibrating system that automatically compensates for external conditions including wind pressure, carpet drag, HVAC stack pressure, and weather stripping friction. It eliminates the seasonal manual adjustments required on conventional operators when these conditions change, reducing service calls and maintaining consistent operation year-round.

What is the LCN 9500 vs 2800 Series Senior Swing?

The 9500 Series is surface mounted: the operator is visible on the door header or adjacent wall. The 2800 Series is overhead concealed: the mechanism is inside the door header cavity. Within each mounting type, models vary by door application: 9530/2810 for single door pull side, 9540/2840 for single door push side, 9550/2850 for simultaneous double door pairs, and 9560/2860 for independent double door pairs.

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Schlage CL Cabinet Lock Parts and HL6 Hospital Latch Lock Parts: Complete Guide Tuesday, June 30, 2026

Security Parts carries parts for the Schlage CL Series cabinet locks and HL6 Series hospital latch locks. CL Series parts include the CL10-301 cylinder retaining screw, CL10-350 adapter spacer, CL10-352 slotted strike, CL10-354 bar strike (1/4 inch thick), CL10-355 bar strike (1/2 inch thick), and Schlage 36-031 trim collar. HL6 Series parts include the HL6 mortise paddle assembly, HL6 tubular paddle assembly, cover assembly, and bent tab mortise strike kit in engraved and non-engraved configurations. The HL6 uses the Schlage L Series mortise chassis. Mortise cylinders and housings are ordered separately from HL6 latches.

Two of the most specialized product categories in commercial door hardware sit in the same part of the SecurityParts.com catalog: Schlage CL Series cabinet locks and Schlage HL6 Series hospital latch locks. They serve completely different applications, but they share a common characteristic: almost every buyer who needs a replacement part struggles to find accurate technical information before ordering. Cabinet lock parts are rarely documented beyond a part number. Hospital latch parts carry healthcare-specific features like anti-barricade key override and lead lining that are absent from most parts supplier content.

Browse the Schlage CL Series cabinet lock parts catalog and the Schlage HL6 hospital latch lock parts catalog at SecurityParts.com. For the complete Schlage commercial hardware range, browse the Schlage commercial hardware catalog.

Full-size Schlage cylinders in CL Series: masterkey-compatible with all door hardware

L Series Mortise chassis used by the HL6 hospital latch for Grade 1 strength

50% Quieter paddle operation on HL6 vs previous HL Series design

1/8" Lead lining thickness inside HL6 lock case for radiation room applications

Schlage CL Series Cabinet Locks: What They Are and Why They Exist

The Schlage CL Series is a cabinet lock line built around the same full-size Schlage cylinders used in commercial door hardware, rather than the smaller wafer-based or cam-type cylinders common in most office furniture locks. This is the design decision that makes the CL Series different from every other cabinet lock on the market.

Standard office furniture locks use low-security wafer cylinders or small tubular cylinders that cannot be masterkeyed into a building's door hardware key system. A facility manager who keys their entry doors to a master system still needs a separate key for every cabinet, which creates key management complexity and the inevitable problem of employees losing multiple keys.

The CL Series solves this by using a standard Schlage cylinder that can be masterkeyed, grand masterkeyed, and keyed alike using the same key system as the building's ND Series cylindrical locks, L Series mortise locks, and B Series deadbolts. One key operates the offices, the storeroom, and the filing cabinets. This is the core specification reason the CL Series is used in commercial and institutional environments rather than standard hardware store cam locks.

The masterkey integration fact no competitor explains at the parts level: When a CL Series cabinet lock is in a masterkeyed system, rekeying it follows exactly the same procedure as rekeying any Schlage door lock. The CL10-301 retaining screw is removed, the cylinder is extracted, and the pins are changed using standard Schlage pinning equipment. No special cabinet lock rekeying tools, no wafer replacement kits, no proprietary service required. Any locksmith equipped to service Schlage door hardware can rekey a CL Series cabinet lock in the same service call. This is why facilities departments that self-service their door hardware can also self-service their CL Series cabinet locks without a separate tool investment.

Schlage CL Series Cabinet Lock Parts: Complete Reference

CL10-301: Cylinder Retaining Screw

The CL10-301 is the set screw that holds the cylinder in the cabinet lock housing. It seats into a detent in the cylinder housing and prevents the cylinder from rotating when the key is turned. When this screw loosens or strips, the entire housing rotates with the key instead of only the cylinder plug rotating. The symptom is a lock where turning the key spins the visible cylinder body rather than producing a bolt movement.

The CL10-301 is the most frequently replaced CL Series part. In high-cycle applications where the lock is opened and locked multiple times daily, the retaining screw vibrates loose over months of use. If a CL Series lock begins to feel loose or the cylinder has visible rotational play when the key is not inserted, check the CL10-301 first before diagnosing the cylinder or bolt mechanism. Tightening or replacing the CL10-301 resolves most CL Series cylinder rotation complaints without any additional parts.

CL10-350: Adapter Spacer

The CL10-350 is a spacer that accommodates thicker cabinet door or drawer face materials. When the cabinet panel is thicker than the standard lock body projection, the spacer extends the lock assembly to the correct mounting depth. Without the correct spacer, the cylinder head may sit below the cabinet face surface, preventing the key from engaging correctly or leaving the retaining screw inaccessible. The CL10-350 is also used when a standard-length CL Series cylinder does not reach the correct bolt engagement depth on a specific cabinet configuration.

CL10-352: Slotted Strike

The CL10-352 is a slotted strike for CL Series cabinet locks. Unlike a fixed-pocket strike, the slotted design allows the bolt to engage anywhere along the slot length rather than at a single fixed point. This accommodates minor misalignment between the bolt position and the frame pocket without requiring strike relocation or additional adjustments. It is the most forgiving strike option for field installations where the cabinet construction tolerance varies.

The slotted strike is the correct first choice for any CL Series installation where the bolt position relative to the frame has not been precisely measured and confirmed. If the bolt position is known and consistent, a bar strike provides a more secure engagement because it has defined pocket walls that prevent the bolt from shifting laterally under load.

CL10-354 and CL10-355: Bar Strikes

The bar strikes are flat bar-shaped strikes with a bolt pocket for the CL Series deadbolt. Both are 3/4 inch wide and 1-31/32 inch long. The CL10-354 is 1/4 inch thick. The CL10-355 is 1/2 inch thick.

The thickness distinction matters for how deep the bolt must travel before engaging the strike. A 1/4 inch bar strike is flush or nearly flush with the cabinet frame face, meaning the bolt engages quickly and with minimal throw distance consumed by the strike material itself. A 1/2 inch bar strike positions the bolt pocket deeper into the frame, requiring more bolt travel to engage. This is used when the gap between the cabinet door and frame requires additional standoff to position the pocket at the correct engagement depth.

Choosing between bar strike thickness: Measure the gap between the closed cabinet door face and the cabinet frame face. If the gap is small (1 to 3mm), the CL10-354 (1/4 inch) is typically correct. If the gap is larger (4 to 8mm), the CL10-355 (1/2 inch) brings the bolt pocket out to meet the bolt at the correct engagement point. A bolt that does not engage the strike fully but still turns the lock mechanism is almost always a bar strike thickness selection error, not a cylinder or bolt failure.

Schlage 36-031: Trim Collar

The Schlage 36-031 trim collar is a cosmetic component that installs around the cylinder face to cover the bore hole in the cabinet panel. When a cabinet panel bore is oversized or the previous lock left a visible gap around the cylinder, the trim collar provides a finished appearance. It also covers minor damage around the bore from forced entry or tool marks. The 36-031 is available in standard finishes to match the cylinder face.

CL Series Lock Configurations: Door vs Drawer

The CL Series offers different cam configurations for door and drawer applications. A door lock uses a deadbolt cam that extends perpendicular to the cylinder body when the key is turned. A drawer lock uses a cam that rotates to release a drawer slide mechanism. The bolt style and cam orientation are specified at the full lock assembly level, not at the individual parts level covered here. When ordering replacement parts, always confirm whether the installation is a door or drawer configuration before ordering any cam or bolt component, as they are not interchangeable between the two applications.

Part Number	Description	When to Order
CL10-301	Cylinder retaining screw	Cylinder housing rotates with key; cylinder has play; retaining screw stripped or loose
CL10-350	Adapter spacer	Cabinet panel thicker than standard; cylinder head sits below flush with panel
CL10-352	Slotted strike	New installation with uncertain bolt position; strike accommodation for minor misalignment
CL10-354	Bar strike, 1/4 inch thick	Cabinet door/drawer gap is small; bolt pocket flush with frame face
CL10-355	Bar strike, 1/2 inch thick	Cabinet door/drawer gap requires standoff; 1/4 inch strike too shallow for full bolt engagement
36-031	Trim collar	Oversized bore; gap around cylinder; cosmetic damage around bore from prior lock

Schlage HL6 Series Hospital Latch Lock: What It Is and Why It Exists

The Schlage HL6 Series hospital latch is a push-pull latch lock designed specifically for healthcare environments. The name comes from its defining feature: a paddle rather than a lever or knob. Instead of gripping and turning hardware, a person pushes or pulls the paddle to retract the latch. The paddle's short throw angle means the latch retracts with a light push or pull force that does not require tight grasping, tight pinching, or twisting of the wrist.

This is not just an ergonomic convenience. It serves three distinct functions in healthcare settings that no standard cylindrical or mortise lever lock satisfies.

First, it enables hands-free door operation. Nurses and doctors carrying equipment, trays, or patients cannot easily grip a lever. A paddle retracted with a forearm or elbow keeps the hands free and the door operational. Second, it delivers quiet operation. The HL Series is specifically engineered to reduce latch engagement and mechanism noise, which is a material factor in patient sleep quality and recovery in room-by-room studies. The current HL6 generation is 50% quieter than the previous HL Series design. Third, it provides institution-specific security functions including anti-barricade key override for behavioral health applications.

The HL6 uses the Schlage L Series mortise lock chassis: the same Grade 1 commercial mortise mechanism used in high-security L Series mortise locks on main building entries. This gives the HL6 the durability required for healthcare environments where doors cycle thousands of times per year under high-traffic, round-the-clock use.

HL6 Series Parts: What SecurityParts.com Stocks

HL6 Mortise Paddle Assembly (Non-Engraved)

For L Series mortise chassis installations

The push-pull paddle for HL6 mortise versions. Works with the L Series mortise lock case inside the door. Non-engraved surface with no directional text or arrows. Paddle dimensions: 1-1/2 inch by 4-1/2 inch with 2-5/8 inch projection from door face. Replace when paddle is physically damaged, bent from impact, or the connection to the mortise mechanism has failed.

HL6 Mortise Engraved Paddle Assembly

For L Series mortise chassis installations

Identical to the non-engraved mortise paddle in all functional respects. Includes directional text or arrows engraved on the paddle face. Engraved paddles are specified when the user population includes patients, visitors, or others who may not be familiar with push-pull latch operation and need a visible cue. Always specify engraved vs non-engraved when ordering to avoid returning the wrong version.

HL6 Tubular Paddle Assembly (Non-Engraved)

For tubular chassis installations

The push-pull paddle for HL6 tubular versions. Used where a full L Series mortise prep is not available or where a lighter-duty installation is acceptable. Functionally equivalent to mortise paddle in push-pull operation. Not compatible with the mortise chassis. Confirm which chassis is installed before ordering.

HL6 Tubular Engraved Paddle Assembly

For tubular chassis installations

Tubular version with directional engraving. Same ordering distinction as the mortise engraved paddle. Confirm tubular (not mortise) chassis is installed before ordering.

HL6 Series Cover Assembly

Cover plate for door face

The cover plate that mounts on the door face and conceals the HL6 mechanism. Damaged or cracked from impact or cleaning chemical exposure. The cover also acts as the trim plate that gives the HL6 its finished appearance on the door. Replacement requires confirming the configuration (mortise or tubular) and finish before ordering.

Bent Tab Mortise Strike Kit

Frame-side strike for HL6 mortise

The HL6 mortise version uses an ASA strike (1-1/4 inch by 4-7/8 inch) as standard. The bent tab mortise strike kit is the optional strike that includes a bent lip configuration for specific frame preparations or when the standard ASA strike does not fit the frame geometry correctly. Always confirm frame prep before ordering any HL6 strike.

HL6 Mortise vs Tubular: Choosing the Right Configuration

The HL6 is available in mortise and tubular versions. The mortise version uses the Schlage L Series mortise lock case installed inside the door, which requires a routed mortise pocket in the door edge. The tubular version uses a standard tubular latch mechanism, which requires only a face bore and edge bore without a mortise pocket.

For new construction healthcare facilities, mortise is almost always the correct specification. The L Series mortise chassis provides Grade 1 strength and durability that matches the high cycle count demands of a hospital patient room door. It is also compatible with the Von Duprin 9875 and 9975 mortise exit devices, which may be required on specific door applications within the healthcare building.

The tubular version is appropriate for renovation projects where the existing doors do not have a mortise prep and the budget does not allow door replacement. A tubular HL6 on an existing tubular prep door provides the push-pull ergonomics and quiet operation of the HL6 without requiring door replacement. The tradeoff is that the tubular version does not achieve the same durability under maximum cycle load as the mortise version.

HL6 cylinders are not included: the ordering omission that delays every healthcare installation: The Schlage HL6 mortise hospital latch does not include mortise cylinders or cylinder housings in the base unit. They must be ordered separately. This is documented in the Schlage specification but is the most frequent cause of installation delay on HL6 projects. A healthcare facility ordering HL6 latches for a patient wing renovation discovers at installation that cylinders were not included and must wait for a separate cylinder order before the doors can be commissioned. Every HL6 order should include a separate line item for the mortise cylinder assemblies at the time of the original order.

HL6 Functions: Healthcare-Specific Security Operations

The HL6 offers 14 mechanical mortise functions, 2 electrified mortise functions, and 3 tubular functions. The functions that matter most for healthcare parts ordering are the ones with specific clinical safety features.

HL6-9010: Passage Function

The latchbolt is retracted by the paddle from either side. Inside paddle always free for immediate egress. The most basic function, used on non-secured interior corridor doors where free passage is always required. Parts for a passage function HL6 are the paddle assembly (mortise or tubular, engraved or non-engraved) and the cover assembly.

HL6-9040: Privacy Function (Bath/Bedroom)

The latchbolt is retracted by the paddle from either side unless the outside paddle is locked by the inside thumbturn. Actuating the inside paddle or closing the door unlocks the outside paddle. For emergency access, the outside has a release mechanism. This is the standard patient bathroom and private room function where a patient needs inside privacy but staff need emergency outside access.

HL6-9060: Apartment Entrance Function

The latchbolt is retracted from either side unless the outside is locked by key from inside. When locked, key or inside paddle retracts the latchbolt. Used on patient rooms where both patient privacy and staff key access are required simultaneously.

HL6-9070: Classroom Function

Latchbolt retracted by paddle from either side unless outside paddle is locked by key. Inside paddle always free for immediate egress. For medication rooms, treatment rooms, and other controlled-access clinical spaces where staff lock access from outside but egress from inside is always free.

HL6-9080: Storeroom Function

Latchbolt retracted by inside paddle or outside key. Outside paddle always inoperative. Auxiliary latch deadlocks latchbolt when door is closed. Inside paddle always free for immediate egress. For medical supply rooms and pharmacy areas where entry is controlled exclusively by key.

HL6-9082: Institution Function (Anti-Barricade)

Latchbolt retracted by key from either side. Outside paddle always inoperative. Inside paddle always free for immediate egress. The key override feature on this function allows the outside key to retract the latch even if the inside is being manually held. This is the anti-barricade function critical for behavioral health, psychiatric, and patient room applications where preventing barricade situations is a clinical safety requirement.

The clinical safety distinction that changes the specification: The difference between HL6-9070 (classroom function) and HL6-9082 (institution function) is the anti-barricade key override. In a classroom function, the inside paddle always retracts the latch, but there is no mechanism for the outside key to override an inside thumbturn being held in the locked position. In the institution function, the key override is present. The distinction is specifically relevant to behavioral health and psychiatric settings where a patient may intentionally barricade a door by physically holding the thumbturn or latch mechanism while inside. Healthcare facilities that specify HL6-9070 on behavioral health patient rooms instead of HL6-9082 are creating a barricade scenario that staff cannot resolve with a key. The correct function for any room where a patient barricade is a clinical risk is HL6-9082 with key override.

HL6 Special Options That Affect Parts Ordering

Lead Lining for Radiation Rooms

The HL6 lock case is available with a 1/8 inch lead lining insert for X-ray rooms, radiation therapy rooms, and any space where the door hardware must contribute to the room's radiation shielding. The lead lining is a factory option, not a field modification. It cannot be added to an existing non-lead-lined lock case.

When a radiation room HL6 needs paddle assembly replacement, the replacement paddle does not include the lead lining. The lead lining is inside the lock case body, not in the paddle. A paddle replacement on a lead-lined HL6 does not require a lead-lined paddle. The case body retains its lead lining throughout the product's life unless the entire lock case is replaced.

If the entire lock case of a lead-lined HL6 must be replaced (due to forced entry damage or mechanism failure), the replacement must be specified with the lead lining option. Ordering a standard non-lined replacement case for a radiation room removes the radiation protection at that opening without any visible indicator that a change has occurred.

Quiet Operation Engineering

The HL Series achieved its documented 50% noise reduction improvement over the previous HL Series generation through redesigned internal mechanism geometry that reduces the impact force of the latch bolt engaging the strike. This is not an adjustable feature and requires no specific maintenance to maintain. However, a correctly aligned strike is necessary for the quiet engagement to function as designed. A misaligned strike that causes the latch to contact the strike face edge rather than enter the bolt pocket cleanly produces noise regardless of the mechanism design. When a previously quiet HL6 installation begins producing latch noise, strike alignment is the first item to check before assuming the mechanism has failed.

Von Duprin Compatibility

The HL6 mortise version is compatible with the Von Duprin 9875 and 9975 mortise exit devices. This allows a single door to be specified with the HL6 push-pull operation on the inside and Von Duprin panic exit hardware on the outside, which is the standard configuration for healthcare patient room doors on required egress paths where both push-pull access and panic hardware are needed simultaneously. This compatibility is not available on the tubular version. Browse commercial exit device parts at SecurityParts.com for Von Duprin mortise exit device components.

Mounting Orientations: What Competitors Never Explain

The HL6 paddle assembly mounts in four orientations that determine how the paddles are positioned relative to the latch: handles up, handles down, one handle up with the other down, or horizontal with handles pointing away from the latch. This flexibility is what allows the HL6 to serve multiple door configurations without a different product for each application.

For corridor patient room doors, handles-down is the most common mounting: the paddles hang below the latch body in the familiar push-pull position that most healthcare workers recognize instinctively. For non-keyed passage functions, handles-up mounting is available, positioning the paddles above the latch body. Horizontal mounting is used when the door configuration requires the paddles to point horizontally rather than vertically.

The mounting orientation that prevents the most common HL6 installation callback: When an HL6 is specified for a door where patients need to operate the lock from bed (common in patient toilet rooms adjacent to patient rooms), the paddle mounting orientation determines whether the patient can reach the lock from a seated or reclined position. Handles-down mounting positions the paddles lower on the door, improving reach for patients who cannot stand fully. The mounting orientation is confirmed at installation, not at ordering. But knowing this before delivery allows the installer to confirm the correct orientation with clinical staff before the lock is commissioned rather than after.

How to Order the Correct Part for Each Product Line

CL Series Cabinet Lock Parts

Three pieces of information are needed: the symptom (cylinder rotates, bolt does not engage, bore is oversized), the application (door or drawer), and the cabinet panel gap dimension (for bar strike thickness selection). The CL10-301 retaining screw resolves most cylinder rotation complaints. The CL10-352 slotted strike is the safest first choice for any new strike installation. Bar strike thickness (CL10-354 vs CL10-355) is determined by measuring the gap between the closed door face and the cabinet frame face.

HL6 Hospital Latch Parts

Four pieces of information are needed: mortise or tubular chassis (confirmed by whether the door has a routed mortise pocket or only bore holes), engraved or non-engraved paddle, function (passage, privacy, classroom, storeroom, or institution), and whether the lock case has lead lining. Cylinders and housings are always ordered separately. For bent tab strike vs standard ASA strike, confirm the frame prep before ordering.

Browse the complete CL Series cabinet lock parts catalog and HL6 hospital latch lock parts catalog at SecurityParts.com. For the full Schlage commercial hardware range including L Series mortise lock parts, ND Series cylindrical lock parts, LT Series tubular lock parts, and B Series deadbolt parts, browse the Schlage commercial hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for Schlage CL and HL6 Parts

CL retaining screw troubleshooting, bar strike thickness guide, HL6 anti-barricade function explanation, cylinder ordering reminder, and same-day shipping on stocked parts.

CL Retaining Screw First

We document that the CL10-301 retaining screw resolves most CL Series cylinder rotation complaints without any additional parts. No other parts supplier explains this diagnostic at the ordering stage.

Bar Strike Thickness Guide

We document how to choose between CL10-354 (1/4 inch) and CL10-355 (1/2 inch) bar strikes by measuring the cabinet gap dimension. Wrong thickness is the most common CL Series parts return.

HL6 Function Safety Context

We document the difference between classroom function and institution function and why the anti-barricade key override is a clinical safety requirement on behavioral health patient rooms, not an optional upgrade.

Same-Day Shipping

Most CL Series and HL6 parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for pre-order configuration support.

What Makes Security Parts Different for These Parts

We document the CL Series masterkey integration advantage: full-size Schlage cylinders in cabinet locks can be masterkeyed with door hardware, eliminating separate cabinet key management. No other parts supplier explains this at the product level.
We document the HL6 cylinder omission: mortise cylinders are not included with HL6 latches and must be ordered separately. This is the most common cause of HL6 installation delay on healthcare projects.
We document the anti-barricade key override as a clinical safety requirement for behavioral health patient rooms, not a security enhancement. The difference between HL6-9070 (no override) and HL6-9082 (with override) is a life-safety specification decision that every healthcare hardware specifier needs to understand.
We document the lead lining in the lock case (not in the paddle) so that a paddle replacement on a radiation room HL6 does not require a lead-lined paddle. No competitor documents which component contains the lead lining.
We carry CL and HL6 parts alongside L Series mortise lock parts, ND Series cylindrical lock parts, and exit device parts for full facility hardware service in one order.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

CL Series cabinet locks and HL6 hospital latch locks are part of larger facility hardware programs. The same healthcare facility using HL6 latches on patient room doors uses L Series mortise locks on staff entries, LCN closers on corridor fire doors, and exit devices on egress stairwells.

For Schlage L Series and Falcon MA Series mortise lock parts on staff office and entry doors in the same healthcare facility, browse the mortise locks catalog. For Schlage ND Series and ALX Series cylindrical lock parts on utility and service doors, browse the cylindrical locks catalog. For Schlage LT and PT Series tubular lock parts on interior non-critical doors, browse the tubular locks catalog. For Schlage B Series deadbolt parts on secondary exit and storeroom doors, browse the deadbolts catalog. For LCN door closer parts on fire-rated corridor doors in healthcare and commercial facilities, browse the door closers catalog. For exit device parts on egress stairwells and fire exit doors, browse the exit devices catalog.

Browse the complete all products and parts catalog to source Schlage, Von Duprin, LCN, Falcon, and Detex hardware across the complete facility in a single session.

Frequently Asked Questions About Schlage CL Cabinet Lock and HL6 Hospital Latch Lock Parts

What is the Schlage CL Series cabinet lock and what parts are available?

The Schlage CL Series uses full-size Schlage cylinders that can be masterkeyed into any existing Schlage door hardware key system. Parts include the CL10-301 cylinder retaining screw, CL10-350 adapter spacer, CL10-352 slotted strike, CL10-354 bar strike (1/4 inch thick), CL10-355 bar strike (1/2 inch thick), and Schlage 36-031 trim collar. CL locks are available for door and drawer applications with different cam configurations.

What is the difference between the Schlage CL10-352 slotted strike and CL10-354 and CL10-355 bar strikes?

The CL10-352 slotted strike accommodates minor misalignment with its slot design. The CL10-354 and CL10-355 are bar strikes with fixed bolt pockets. The CL10-354 is 1/4 inch thick for installations where the cabinet gap is small. The CL10-355 is 1/2 inch thick for installations where additional standoff depth is needed. Measure the closed cabinet door-to-frame gap before selecting bar strike thickness.

What is the Schlage HL6 Series hospital latch lock and where is it used?

The HL6 uses a push-pull paddle on the Schlage L Series mortise chassis. It allows hands-free door operation with a short throw angle and delivers quiet latch engagement (50% quieter than the previous HL Series). Used on patient room doors, medication rooms, treatment rooms, and restrooms in healthcare environments. Available in mortise and tubular versions with 14 mechanical mortise functions, 2 electrified functions, and 3 tubular functions.

What is the HL6 anti-barricade key override and why is it critical in healthcare?

Anti-barricade key override allows the outside key to retract the deadbolt or latchbolt even when the inside thumbturn is being held in the locked position. In behavioral health and psychiatric settings, this prevents a patient from barricading a door and blocking staff access. The institution function HL6-9082 includes key override. The classroom function HL6-9070 does not. Every HL6 installation in a behavioral health patient room should specify the institution function with key override.

What is the HL6 lead lining option and what rooms require it?

The HL6 lead lining is a 1/8 inch thick lead insert inside the lock case for X-ray rooms and radiation therapy rooms. It is a factory option, not a field modification. The lead lining is in the lock case, not the paddle, so paddle replacement does not require a lead-lined paddle. If the entire lock case is replaced on a radiation room installation, the replacement must be specified with the lead lining option.

What is the difference between the HL6 mortise paddle and the HL6 tubular paddle assembly?

The HL6 mortise paddle works with the L Series mortise lock case inside the door and provides Grade 1 strength for high-cycle healthcare applications. The tubular paddle works with a tubular latch mechanism for doors without a mortise prep. Both are available in engraved and non-engraved versions. Engraved paddles show directional text or arrows. Confirm which chassis is installed (mortise prep in the door edge vs bore-only) before ordering either assembly.

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Detex Exit Alarm and Door Hardware Parts: ECL, EAX, ADVANTEX and AO19 Complete Guide Monday, June 29, 2026

Security Parts carries parts for all Detex product lines. The ECL-230D is a complete battery-alarmed exit control lock with a 1-inch deadbolt and push bar. The EAX-500 is a surface-mounted battery door alarm that pairs with existing hardware. ADVANTEX is the super-heavy-duty exit device line for high-abuse applications. The AO19 is a low-energy automatic door operator for ADA-compliant hands-free access. The MC65 mortise cylinder (1-1/8 inch, Schlage C keyway) is the standard cylinder for ECL and EAX Series. The ECL-445K is the IKC lock cylinder replacement for the ECL-230D. The ECL-405-KIT is the cover lock key kit for both ECL and EAX series cover locks.

Detex has been manufacturing commercial door security hardware for over a century. The product line covers a wider range of functions than most commercial hardware brands: from the simple battery-powered EAX-500 door alarm through the complex ADVANTEX super-heavy-duty exit device with full electrified integration, to the AO19 automatic door operator for ADA-compliant accessibility applications. Each product line has its own parts ecosystem with specific cylinder, cover, and accessory requirements.

Browse the complete Detex hardware parts catalog at SecurityParts.com, covering all Detex product lines including ADVANTEX, Value Series, ECL, EAX, AO19, 90 Series, and Detex Trims. For the full exit alarm range including Detex ECL and EAX alongside the Von Duprin Guard-X alarm series, browse the commercial exit alarm parts catalog.

100dB Alarm output on ECL-230D and EAX-500 Series

2,200 lbs Outside pull force resistance on the Detex ECL-230D

9V Battery type on ECL-230D and EAX-500; 1 to 3 year life under normal use

3-year Detex limited electrical warranty on ECL and EAX Series products

The Detex Product Lines: What Each One Is and Does

ECL Series

Exit Control Lock | Code-Compliant Panic Device

Complete panic exit hardware with battery alarm. The ECL-230D is a push-bar deadbolt device with 1-inch throw, 100dB alarm, and photo-luminescent sign. Meets life safety panic requirements. Used on secondary exits, back doors, and restricted commercial egress points. The ECL-230X is the ultra-rugged break-in prevention version with hardened deadbolt.

EAX Series

Door Alarm | Surface Mount Battery Alarm

Battery-powered surface alarm, not a panic device. Mounts on door or wall and uses magnetic contact to trigger 100dB alarm when door is opened without key authorization. The EAX-500 is the standard model. The EAX-500W is the weatherized outdoor version. The EAX-2500 is the flush-mount version. No push bar, no deadbolt. Adds alarm monitoring to existing hardware.

ADVANTEX

Super-Heavy-Duty Exit Devices | High Abuse

Premium exit device line for schools, hospitals, airports, retail, and other high-abuse environments. Available in rim (10 Series), surface VR (20 Series), mortise (30 Series), narrow stile rim (40 Series), and concealed VR (60 Series). Stainless steel and vapor deposition finishes. Widest electrified option range of any Detex exit device. Custom lengths 24 to 48 inches. 3-hour UL fire rating on steel doors.

AO19 Series

Low-Energy Automatic Door Operator | ADA Access

Not an alarm or exit device. Automatic door opener that mounts in the door header and opens and closes the door on a push button or access control signal. Meets ANSI/BHMA A156.19. ADA compliant. AO19-1 for single doors, AO19-2 for double doors, AO19-3 for double egress applications. 115VAC, obstruction reversal, ON/OFF/HOLD switch. Used in healthcare, commercial, and accessibility-required applications.

Value Series

Mid-Range Exit Devices | Standard Commercial

The Detex V40xNS is a narrow stile rim exit device for standard commercial applications where ADVANTEX-level construction is not required. Available in standard configurations and finishes. Lower price point than ADVANTEX but still meeting ANSI Grade 1 requirements for panic hardware.

90 Series

Surface Alarm | Door Prop Alarm

The Detex 90 Series covers surface-mounted alarm products including door prop alarms. The EAX-300 Series monitors doors that may be used for egress but must not be held open, with adjustable open-time detection from 1 second to 4 minutes. The EAX-411SK is an AC-powered door prop alarm for controlled-access doors. Used where monitoring door-prop violations is the primary concern rather than unauthorized egress.

What Is the Detex ECL-230D and How Does It Work

The ECL-230D is the most widely misidentified product in the Detex line. It is not simply an alarm that gets added to a door. It is a complete panic exit control lock: a deadbolt with a push bar that meets life safety code requirements for panic hardware, combined with a battery-powered 100dB alarm system in a single unit.

When the deadbolt is in the locked position and the push bar is pressed, the bolt retracts for emergency egress and the alarm sounds simultaneously. The alarm can only be reset with a control key. The locking and unlocking of the deadbolt automatically arms and disarms the alarm respectively. This is the fundamental distinction from the EAX-500: pressing the ECL push bar both unlocks the door for egress and sounds the alarm. The EAX-500 only sounds an alarm; it does not control any locking mechanism.

ECL-230D Physical Specifications

The ECL-230D fits wood, hollow metal, and aluminum doors from 1-3/4 to 2-1/4 inches thick. The minimum standard door width is 20 inches. The design is non-handed, so the same unit installs on left-hand or right-hand doors. The attack-resistant design withstands over 2,200 pounds of outside pull force. The 1-inch throw deadbolt is saw-resistant. The lock body is made from corrosion-resistant alloy. The photo-luminescent sign absorbs ambient light and glows in the dark when lighting fails, meeting egress marking requirements without battery backup lighting.

The ECL-230D accepts 5-pin through 7-pin standard and interchangeable core rim cylinders. The IKC (Inside Key Control) cylinder is the ECL-445K. The OKC (Outside Key Control) uses rim cylinders. The cover lock is the mechanism that holds the cover assembly to the backplate and requires a separate cover key to access the battery compartment.

ECL-230D vs ECL-230X: Choosing the Right Version

The ECL-230X is the higher-security version of the ECL-230D. The key differences are a hardened deadbolt for break-in prevention and inclusion of the photo-luminescent sign as a standard component. Both versions produce a 100dB alarm and meet the same life safety code requirements. For most commercial secondary exit applications, the ECL-230D is the correct specification. For back doors on high-theft-risk retail environments, warehouses, and facilities with documented forced entry attempts, the ECL-230X provides additional resistance without changing the operating interface.

The IKC key confusion that generates most ECL-230D service calls: The ECL-230D has two key systems that look similar but do completely different things. The IKC (Inside Key Control) key rotates a full 360 degrees to throw the deadbolt from inside. The OKC (Outside Key Control) is a standard rim cylinder key used from outside. The cover key is a third separate key that releases the cover to access the battery. Facilities that lose track of which key is which generate repeated service calls that conclude only with physical identification of each key by its cylinder. The cover key, IKC key, and OKC key are all different and non-interchangeable. A complete key audit of any ECL-230D installation should document all three before any key is misplaced.

Detex EAX-500: Battery Door Alarm Parts and Configuration

The EAX-500 is a surface-mounted battery alarm designed for doors that need an audible deterrent without replacing the existing door hardware. It mounts on the door face or adjacent wall and uses a magnetic contact pair (one half on the door, one half on the frame) to detect door opening. When the door opens and breaks the magnetic contact, the piezo horn sounds at approximately 100dB.

EAX-500 Cylinder Configuration

The EAX-500 comes standard without a cylinder. Key control is optional:

Option	Part	Function	Location
Inside key control	MC65	Mortise cylinder, 1-1/8 inch, Schlage C keyway, 6-pin	Bottom of EAX-500 unit (inside face)
Outside key control	RC65	Rim cylinder for outside face	Outside face of door
Interchangeable core	IC7	7-pin IC housing, compatible with most standard 7-pin IC format cores	Pre-installed at factory, field core insertable
Cover lock key kit	ECL-405-KIT	Cover lock key kit for covers on ECL and EAX Series	Cover assembly on both ECL and EAX devices

The patented cam assembly inside the EAX-500 automatically adjusts for different cylinder sizes without requiring spacers. This is a genuine engineering advantage over competitor alarms where spacers must be sourced separately for non-standard cylinder lengths. The EAX-500's cam system accepts any standard mortise cylinder within the common range without modification.

EAX-500 Battery and Operation

The EAX-500 runs on a 9VDC battery. Low battery is indicated by an LED visual alert. The alarm can only be silenced by the proper control key. The extended bypass feature is standard: when the door is legitimately propped open (during a delivery or loading), the alarm remains bypassed and automatically rearms when the door closes. This prevents the nuisance alarm scenario where a propped door on a loading dock triggers continuous alarm until someone manually resets it.

The intelligent circuit automatically senses the magnet location on the door and sets the correct handing for the unit. This means the same EAX-500 unit installs correctly regardless of whether the door opens left or right, without any configuration switch adjustment. This self-handing feature is a field installation advantage that competitors' alarms do not universally offer.

EAX-500W: The Weatherized Version

The EAX-500W is the weatherized version for outdoor applications including exterior secondary exits, gate alarms, and doors exposed to direct weather. The weather-resistant housing adds moisture protection without changing the operational interface. All cylinder options available on the standard EAX-500 are available on the EAX-500W. For any Detex door alarm installation on a door exposed to direct precipitation or sustained humidity, always specify the EAX-500W rather than the standard EAX-500.

ECL and EAX Parts Reference: What to Order for Each Failure

Part Number	Description	Applies To	When to Order
ECL-445K	IKC lock cylinder, ECL-230D	ECL-230D	IKC cylinder stiff, binding, or key will not turn
ECL-445K-7	IKC lock cylinder, 7-pin version	ECL-230D	When 7-pin cylinder is required for higher security pinning
ECL-1576-15	Cam bridge assembly and lock cylinder housing	ECL-230D	Cam bridge damaged; housing cracked from forced entry
MC65	Mortise cylinder, 1-1/8 inch, Schlage C keyway	ECL-230D, EAX-500, EAX-2500	Cylinder key stiff, worn, or inside key control lost
RC65	Rim cylinder for outside key control	ECL-230D, EAX-500	Outside key control required; cylinder worn or lost
IC7	7-pin interchangeable core housing	ECL-230D, EAX-500	Facility uses IC key system; needs rekeying without cylinder replacement
ECL-405-KIT	Cover lock key kit	ECL and EAX Series	Cover key lost; cover lock replacement required for battery access
102665	Magnet kit	EAX-500, EAX-2500	Magnetic contact lost, damaged, or door/frame separation too wide for existing magnet

The cover lock kit without which the battery cannot be changed: The ECL-405-KIT cover lock key kit controls the cover lock mechanism on both ECL and EAX Series units. Without the correct cover key, the cover cannot be opened to access the battery compartment. The most common post-installation failure on ECL and EAX Series devices is a facility discovering the cover key has been lost when the battery dies and the alarm stops functioning. Unlike many hardware keys, the cover key for the ECL and EAX is not a standard profile and cannot be duplicated at a hardware store. Facilities should always record the cover key code at installation and store a spare. The ECL-405-KIT provides a new key set when the original is lost.

Battery Replacement Procedure: ECL-230D and EAX-500

Both the ECL-230D and EAX-500 use 9-volt batteries accessed through the cover assembly. The procedure differs slightly between the two but follows the same sequence.

ECL-230D Battery Access

To access the ECL-230D battery: insert the cover key into the cover lock and turn counterclockwise until the cover releases. Swing the cover away from the backplate. The 9-volt battery is visible and accessible. Confirm battery voltage is a minimum of 7 volts if any doubt exists about the current battery condition. Replace with a fresh 9-volt battery, reconnect the battery terminal, and confirm all wiring connections are intact before closing the cover. Swing the cover back to the backplate and re-engage the cover lock. Test alarm function by pressing the push bar with the IKC in the locked position. The alarm should sound immediately.

EAX-500 Battery Access

The EAX-500 cover lock uses the cam lock at the top of the unit for cover access. Insert the cover key into the cam lock and release the cover. Replace the 9-volt battery and confirm LED arming indicators function on cover reinstallation. The EAX-500 includes LED visual and audible arming indicators that confirm correct operation after battery replacement. If the LED indicators do not respond correctly after a fresh battery installation, check the battery terminal connection and confirm the magnetic contact sensor is properly positioned before concluding the board has failed.

The annual battery replacement that eliminates 80% of Detex alarm service calls: Both the ECL-230D and EAX-500 operate with a 9-volt battery that functions for 1 to 3 years depending on activation frequency. The most common service complaint on both devices is alarm failure with no apparent cause. In the vast majority of these cases, a battery that reads slightly above the 7-volt minimum will cause intermittent function that appears to be electronic failure. Scheduling annual battery replacement as part of building preventive maintenance eliminates this failure mode entirely. The cost of one service call typically exceeds several years of annual battery replacement on all devices in a building.

Detex ADVANTEX Exit Devices: Heavy-Duty Series Guide

The ADVANTEX line is Detex's response to high-abuse commercial applications where standard exit devices suffer accelerated wear. Schools, hospitals, airports, corrections, and retail environments with high daily cycle counts benefit from the ADVANTEX construction: stainless steel, vapor deposition finishes, and the widest electrified option set in the Detex lineup.

ADVANTEX Series by Configuration

Series	Configuration	Stile	Application
10 Series	Rim exit device	Wide (4-1/2 inch minimum)	Heavy-duty single and double doors with mullion; highest use interior and exterior egress
20 Series	Surface vertical rod	Wide	Heavy-duty doors without mullion; two-point latching on single doors
30 Series	Mortise exit device	Wide (4-1/2 minimum)	Maximum security and durability with mortise lock body; high-security perimeter doors
40 Series	Narrow stile rim	Narrow (aluminum storefront)	High-use aluminum storefront entries requiring narrow stile panic hardware
60 Series	Concealed vertical rod	Wide	Heavy-duty doors requiring clean exterior face without visible rod hardware

ADVANTEX Electrified Options

Detex markets the ADVANTEX as having the most comprehensive electrified option set of any exit device in the industry. Available options include electric latch retraction (EL), electric integration (EI), alarm exit (EA), electric bridge (EB), delayed egress (EE), and electric latch monitoring. The EI option connects the exit device to building automation systems, access control panels, and security monitoring platforms, making the ADVANTEX appropriate for high-security environments that require centralized door status reporting.

Fire-rated ADVANTEX devices support 3-hour UL listing on steel doors. The F prefix designates fire-rated versions (for example, F6001 for the 60 Series fire version). Custom lengths from 24 to 48 inches are available. Devices shorter than 30 inches have restrictions on which electrified options are available; always confirm electrified option availability against the device length before specifying.

ADVANTEX Cylinder and Trim Accessories

ADVANTEX devices are ordered without cylinders as standard. Cylinders (C65) or interchangeable core housings (IC7) are pre-installed at the Detex factory when specified at order time. Knurling (KN), antimicrobial finish (AM), and lever switch (LS) options add to the base price. Lever trims for ADVANTEX are specified by function: key retracts latch (C), night latch (NL), dummy trim (DT), and blank escutcheon (BE). Lever trim handing must be specified (RHR or LHR) unless ordering exit-only configurations.

Detex AO19 Automatic Door Operator: What It Is and What Fails

The AO19 is categorically different from every other Detex product. It is not an alarm and it is not an exit device. It is a low-energy automatic door opener that mounts in the door header and powers the door open and closed using a motor-driven mechanism. Understanding what it is prevents it from being ordered to solve an alarm or exit hardware problem.

The AO19 is used on accessibility routes in commercial buildings where ADA requires hands-free door access: healthcare facility corridors, accessible restroom entries, building main entries on accessible routes, and any interior door on a required accessible path where manual door operation would present a barrier for mobility-impaired users.

AO19 Configurations: Single, Double, and Double Egress

The AO19-1 serves single doors. The AO19-2 serves double doors where both leaves open together on a single signal. The AO19-3 serves double egress applications where both doors open away from each other for bidirectional traffic. Each configuration requires separate operators for each leaf. The AO19-2 requires cable synchronization between the two operators for coordinated operation on double door pairs.

AO19 Electrical Requirements and Features

The AO19 runs on 115VAC from a standard outlet. The power source plugs into the header unit. A 3-way low-voltage ON/OFF/HOLD switch controls service and operational modes without requiring line voltage access. The obstruction reversal feature stops the door during a closing cycle and re-activates to open if an obstruction is sensed before the door reaches the latch position. This is the safety interlock that prevents the door from closing on a person or object in the opening.

The AO19 connects to existing access control systems, locking hardware, and building computer signals. A credential read or a wall-mounted push button activation signal triggers the operator to open the door. The controller module inside the operator can be adjusted for opening speed, hold-open time, and closing speed without special tools. Parts for the AO19 include the cover (aluminum or bronze finish), cable sync for twin AO19 UDC 1000 installations (part 104707), and motor/gearbox assemblies documented in the push and pull repair manuals available from Detex.

Detex vs Von Duprin Guard-X: Exit Alarm Comparison

SecurityParts.com carries both Detex and Von Duprin exit alarm products. They serve similar applications but with different design philosophies that affect which one is correct for a specific opening.

The Von Duprin Guard-X 2670 is a single-point rim exit alarm device that is the Von Duprin equivalent of the Detex ECL-230D. Both are battery-alarmed push-bar deadbolt devices meeting panic hardware requirements. The Guard-X uses a Von Duprin cylinder ecosystem while the ECL-230D uses its own IKC cylinder system with the ECL-445K. Facilities that have standardized on Von Duprin cylinders throughout a building may prefer the Guard-X to maintain key system continuity. Facilities that have standardized on Detex hardware or Schlage C keyway cylinders find the ECL series integrates more cleanly into their existing key schedule.

Browse the complete Von Duprin exit device and alarm range at the Von Duprin parts catalog. For the full exit alarm parts range including both Detex ECL and EAX series and the Von Duprin Guard-X, browse the exit alarm parts catalog.

How to Order the Correct Detex Part

Three pieces of information are required before any Detex parts order.

1. Product line (ECL, EAX, ADVANTEX, AO19, Value Series, 90 Series): Visible from the product label on the device. The full model number is on a label on the back plate or side of the unit. For ECL-230D, the model number confirms whether the standard or X (hardened deadbolt) version is installed.

2. Part type (cylinder, cover lock, cam bridge, magnet, cover assembly): Identifying which component has failed determines whether the order is the ECL-445K cylinder, the ECL-1576-15 cam bridge assembly, the ECL-405-KIT cover lock key kit, or the 102665 magnet kit.

3. Cylinder format (standard 5-7 pin, or IC): Confirm whether the installation uses standard conventional cylinders or IC format cores before ordering any replacement cylinder. The IC7 housing is required for IC installations, and the correct IC core must be sourced separately to insert into the IC7 housing.

Browse the complete Detex parts catalog at SecurityParts.com for all ECL, EAX, ADVANTEX, AO19, Value Series, and 90 Series components. Browse the full exit alarm catalog for Detex and Von Duprin alarm products side by side. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose Security Parts for Detex Parts

IKC vs OKC vs cover key documentation, battery life facts, ADVANTEX electrified option guidance, and same-day shipping on stocked components.

Three-Key Documentation

We document the IKC, OKC, and cover key as three distinct key systems on the ECL-230D. Confusion between these generates most ECL service calls. We resolve this before the order is placed.

Battery Maintenance Facts

We document that annual 9-volt battery replacement eliminates 80%+ of ECL and EAX alarm failure calls. A fresh battery costs pennies compared to a service call. We say this directly.

AO19 Correct Identification

We document that the AO19 is an automatic door operator, not an alarm or exit device. This prevents AO19 parts from being ordered for alarm or exit device problems.

Same-Day Shipping

Most Detex ECL, EAX, and ADVANTEX parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for parts identification support.

What Makes Security Parts Different for Detex Parts

We document the ECL-405-KIT cover lock key kit as the part that provides battery access when the cover key is lost. Most facilities discover the cover key is missing only when the battery dies. This part and its purpose is undocumented at most parts supplier sites.
We document the EAX-500 extended bypass feature that keeps the alarm from triggering when a door is legitimately propped open. This feature prevents the most common nuisance alarm complaint on EAX-500 installations near loading docks.
We document the EAX-500 self-handing intelligent circuit as a genuine installation advantage over competitor alarms. Most parts suppliers describe the EAX-500 specifications without explaining why the self-handing feature matters for field installation.
We document that ADVANTEX devices shorter than 30 inches have electrified option restrictions. Specifiers who do not know this order incompatible EL or EA options for short-length devices and receive field mismatches.
We carry Detex parts alongside Falcon and Von Duprin exit device parts, LCN door closer parts, Schlage cylindrical lock parts, and mortise lock parts for complete building hardware service in one order.
Free shipping on orders over $450. Same-day shipping on stocked parts from US warehouses. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

Detex hardware appears on doors throughout commercial buildings alongside other hardware brands. The same building that uses Detex ECL-230D locks on secondary exits likely uses Von Duprin on main egress stairwells, LCN closers on fire-rated corridors, and Schlage cylindrical locks on office doors.

For commercial exit alarm parts including the full Detex ECL and EAX range alongside Von Duprin Guard-X parts, browse the exit alarms catalog. For commercial exit device parts including Falcon 19, 24, 25 Series and all Von Duprin series, browse the exit devices catalog. For Von Duprin exit device and alarm parts on doors where Von Duprin is specified alongside Detex, browse the Von Duprin catalog. For LCN door closer parts on fire-rated corridor doors in the same building, browse the door closers catalog. For Schlage ND Series cylindrical lock parts on office and interior doors in the same facility, browse the cylindrical locks catalog.

Browse the complete all products and parts catalog to source Detex, Von Duprin, Falcon, Schlage, LCN, and all other supported brands in a single session.

Frequently Asked Questions About Detex Parts

What is the difference between the Detex ECL-230D and EAX-500?

The ECL-230D is a complete panic exit control lock with a 1-inch deadbolt, push bar, and 100dB alarm that meets life safety code. Pressing the bar retracts the bolt for emergency egress and sounds the alarm. The EAX-500 is a surface-mounted battery alarm with no deadbolt and no push bar. It mounts on the door face and sounds when the magnetic contact is broken by door opening. The ECL-230D replaces the door hardware. The EAX-500 adds alarm monitoring to existing hardware without replacing it.

What battery does the Detex ECL-230D use and how long does it last?

A 9-volt battery. Under normal conditions of 1 to 2 alarm activations per day, battery life is 1 to 3 years. The battery is accessed by opening the cover with the cover key. A minimum voltage of 7 volts is required. Annual replacement as part of routine inspection is recommended. Most ECL alarm failure calls are resolved by replacing a battery that reads low on a meter but still above minimum voltage.

What cylinder does the Detex EAX-500 use and how is key control configured?

Cylinders are not included with the standard EAX-500. For inside key control, the MC65 mortise cylinder (1-1/8 inch, Schlage C keyway, 6-pin) mounts in the bottom of the unit. For outside key control, the RC65 rim cylinder is required. The IC7 7-pin interchangeable core housing is available for IC key systems. The ECL-405-KIT provides cover lock key replacement for both ECL and EAX Series.

What is the Detex ADVANTEX exit device and where is it used?

ADVANTEX is Detex's super-heavy-duty exit device line for high-use, high-abuse environments including schools, hospitals, airports, retail, and corrections. Available in rim (10 Series), surface VR (20 Series), mortise (30 Series), narrow stile rim (40 Series), and concealed VR (60 Series). Stainless steel and vapor deposition finishes. Custom lengths 24 to 48 inches. 3-hour UL fire rating on steel doors. Widest electrified option range of any Detex exit device.

What is the Detex AO19 and what does it do?

The AO19 is a low-energy automatic door operator that mounts in the door header and opens and closes the door automatically on a push button or access control signal. It is not an alarm or exit device. It meets ANSI/BHMA A156.19 and provides ADA-compliant hands-free access. AO19-1 for single doors, AO19-2 for double doors, AO19-3 for double egress. Runs on 115VAC with obstruction reversal and ON/OFF/HOLD service switch.

What is the Detex ECL-445K and what does it replace?

The ECL-445K is the IKC lock cylinder replacement for the ECL-230D exit control lock. It controls the deadbolt throw from inside. Order ECL-445K-7 for the 7-pin version. When the cylinder is difficult to turn, stiff, or the IKC key no longer operates the deadbolt, the ECL-445K is the correct replacement. The ECL-1576-15 is the cam bridge assembly and lock cylinder housing, needed when the housing itself is damaged rather than just the cylinder plug.

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Falcon 19, 24 and 25 Series Exit Device Parts: Complete Replacement Guide Friday, June 26, 2026

Security Parts carries parts for all three Falcon exit device series. The 19 Series is narrow stile, light-to-medium duty, rim and SVR only. The 24 Series is narrow stile, heavy duty, for aluminum storefront doors with stiles as narrow as 1-3/4 inches. The 25 Series is wide stile, heavy duty, for standard hollow metal and wood commercial doors. The 24 and 25 Series share a push pad design and the same service manual (108004). The most frequently replaced parts are the channel, end cap kit, dogging cover plate, and on electrified versions, the EL solenoid or HWEA alarm board. For pre-June 2012 alarm assemblies, the HWEA replacement board is part 650335.

Falcon exit devices are on more commercial egress doors in North America than any other panic hardware brand outside Von Duprin. The 19, 24, and 25 Series cover the full range of commercial applications: from light office and retail doors through aluminum storefront entries to institutional hollow metal fire-rated assemblies. Each series has distinct construction, stile requirements, and electrified option sets. Getting the right replacement part requires knowing which series is installed and which sub-configuration applies.

Browse the complete Falcon exit device parts catalog at SecurityParts.com, which includes the 19, 24, and 25 Series alongside the full Von Duprin and Detex exit device range. The Falcon hardware catalog covers all Falcon product lines including exit devices, mortise locks, and cylindrical locks.

Grade 1 ANSI/BHMA A156.3 certification on all three Falcon series

108004 Shared service manual number for 24 and 25 Series

June 2012 HWEA alarm assembly redesign date affecting board compatibility

24V DC EL solenoid voltage, 0.34A continuous duty on 24 and 25 Series

Falcon 19 vs 24 vs 25 Series: Which One Is Installed

Before ordering any replacement part, identifying the series is mandatory. The three series look similar from a distance but are built for completely different door constructions. Ordering a 25 Series end cap for a 24 Series device, for example, produces a part that will not fit.

Falcon 19 Series

Narrow Stile | Light-to-Medium Duty

For interior or exterior single and double doors where traffic is not consistently heavy. Stile as narrow as 1-3/4 inches. Covers a 161 door prep for easy field retrofit. Rim (19-R) and surface vertical rod (19-V) configurations only. Non-handed. Optional 1-1/2-hour B label fire rating (F-19). Three finishes: SP28, SP313, US32D. 10-year warranty.

Falcon 24 Series

Narrow Stile | Heavy Duty | Aluminum Storefronts

Heavy-duty extruded aluminum construction for aluminum storefront doors with stiles as narrow as 1-3/4 inches. Rim (24-R), surface vertical rod (24-V), concealed vertical rod (24-C), and wide door cable (24-CWDC) configurations. Half-turn hex dogging standard. All mounting screws concealed. Shares push pad design and service manual 108004 with 25 Series. EL not available on 24 fire rim devices.

Falcon 25 Series

Wide Stile | Heavy Duty | Hollow Metal and Wood

Wide stile heavy-duty device for standard commercial hollow metal and wood doors. Minimum 4-1/2-inch stile (3-1/2-inch on 25-C concealed VR). Rim (25-R), surface vertical rod (25-V), concealed vertical rod (25-C), wide door cable (25-CWDC), and mortise (25-M) configurations. Half-turn hex dogging standard. Heavy wrought center case with sintered metal parts. 10-year warranty. UL A label (3-hour) on fire-rated versions.

The identification test that takes 30 seconds: Look at the door stile width where the exit device is mounted. If the stile is narrow aluminum (typical of glass-heavy storefront entries), it is a 24 Series. If the stile is a standard hollow metal or wood door stile (4-1/2 inches or wider), it is likely a 25 Series. If it is a lighter interior door without heavy aluminum storefront construction, it may be a 19 Series. Confirm by looking at the channel. The 19 Series channel has a narrower profile and black plastic end caps on standard finishes. The 24 and 25 Series both have flush stainless steel push pads and no exposed screws or rivets on the back of the device.

What Exit Device Configurations Mean for Parts Ordering

Each series offers multiple configurations that determine which latch hardware, rods, and strikes are involved. The configuration suffix on the model number tells you what is installed.

Suffix	Configuration	Latching	Application
-R	Rim exit device	Single-point, rim latch at device head	Standard single doors, paired doors with mullion
-V	Surface vertical rod	Two-point: top latch at device head, bottom rod to floor	Single doors, double doors without mullion
-C	Concealed vertical rod	Two-point: rods run inside door stile	Doors requiring clean exterior face with no exposed hardware
-CWDC	Wide door cable/concealed, wood door	Two-point concealed for wood door construction	Wide or wood doors requiring concealed rod hardware
-M	Mortise exit device	Mortise lock case inside door, device operates latch	Heavy-duty perimeter doors requiring mortise body strength; 25 Series only
F- prefix	Fire-rated version	Same as panic version but fire-listed	Any fire-rated door assembly; cannot be dogged

Why the Rim vs Vertical Rod Distinction Matters for Parts

A rim device has one latch point at the device head and uses a single rim strike on the door frame. A surface vertical rod device adds a bottom rod running from the device head to a floor bolt, creating two-point latching. The bottom rod, floor strike, and bottom latch components are additional parts unique to vertical rod configurations that rim devices do not use. If you are ordering a strike or latch bolt replacement, you need to know whether the installation is rim or VR before ordering.

The 25-V surface vertical rod uses a 3788 surface-applied top strike and a 2130 mortised bottom floor strike as the standard configuration. The 25-C concealed VR uses a 4188 mortised top strike and 2130 bottom standard, with 4155 and 2126A as bottom options. Fire-rated 25-C uses strike 1279 standard and F1280 for B label applications.

Falcon 19 Series Parts: Channels, End Caps and Key Components

The 19 Series uses a narrower channel profile than the 24 and 25 Series. All mounting screws are concealed; latch fasteners are exposed to the egress side. The push bar height is 1-3/4 inches. The stainless steel latch bolt has a 3/4-inch throw with deadlocking standard.

Part Number	Description	Notes
4107	19 Series channel, 3-foot door	Standard channel for doors up to 3 feet
4108	19 Series channel, 4-foot door	Standard channel for doors up to 4 feet
650343	19 Series channel end cap kit (with screws)	Includes end cap, bracket, and all mounting hardware
650320	19 Series end cap mounting bracket with SNB	Bracket only, for bracket replacement without full kit
4122	Sex bolt, package of 1 (includes machine screw)	Mounting fastener; #10-20 thread
650360	F-19 channel cover plate, 3-foot (fire)	Fire-rated version only, 3-foot door
650361	F-19 channel cover plate, 4-foot (fire)	Fire-rated version only, 4-foot door
650297	19 Series panic hex dogging channel cover, 4-foot	Panic (non-fire) version, 4-foot door
650303	19 Series panic hex dogging channel cover, 3-foot	Panic (non-fire) version, 3-foot door

Pre-June 2012 alarm assemblies on 19 Series: For 19 Series installations with an exit alarm option built before June 2012, the replacement HWEA hard-wired exit alarm circuit board is part 650335. This board is not compatible with post-June 2012 alarm assemblies. The June 2012 redesign changed the alarm kit architecture, and using the 650335 board in a newer assembly will result in a non-functional alarm. Check the date code on the existing board before ordering any alarm board replacement.

Falcon 24 Series Parts: Heavy Duty Narrow Stile

The 24 Series is built from extruded aluminum for maximum strength on narrow stile aluminum storefront doors. The construction provides greater impact resistance than the 19 Series at the same stile width. The push pad design is shared with the 25 Series, which is why both reference the same service manual 108004.

Part Number	Description	Notes
661408	24 Series channel, 3-foot door	Extruded aluminum construction
661409	24 Series channel, 4-foot door	Extruded aluminum construction
650294	24 Series channel end cap kit, 1-3/4-inch door	Kit includes end cap, bracket, and all fasteners for standard door thickness
650348	24 Series channel end cap kit, 2-1/2-inch door	Kit for thicker than standard door applications
650147	24/25 Series EL kit, 3-foot device	Electric latch retraction for 3-foot channel devices
650148	24/25 Series EL kit, 4-foot device	Electric latch retraction for 4-foot channel devices

The 24 Series Door Thickness and End Cap Selection

The 24 Series serves aluminum storefront doors that come in two standard thicknesses: 1-3/4 inches (the most common commercial aluminum frame door) and 2-1/2 inches (thicker commercial storefront systems). The end cap kit part number changes based on this dimension. Part 650294 is for the 1-3/4-inch door and part 650348 is for the 2-1/2-inch door. Ordering the wrong kit produces an end cap that either leaves a gap at the stile edge or cannot seat against the door face at the correct depth.

The 24 Series EL restriction nobody documents at the part level: Electric latch retraction (EL) is available on 24 Series panic rim, panic SVR, and panic CVR devices. It is specifically not available on 24 Series fire rim (F-24-R) devices. Life safety code prohibits holding the latch retracted on a fire-rated rim device using an always-on EL solenoid. If the installation has a fire label on the door and uses a 24-R configuration, the EL kit (650147 or 650148) does not apply to that opening regardless of what the wiring diagram suggests. This restriction catches facility managers who upgrade access control on fire-door openings without checking the device configuration first.

Falcon 25 Series Parts: Wide Stile Heavy Duty

The 25 Series is Falcon's flagship exit device for standard commercial hollow metal and wood door applications. The center case is heavy wrought with sintered metal parts throughout the mechanism, making it more durable than extruded-only construction under heavy cycle loads. The top latchbolt is stainless steel with a 3/4-inch throw and deadlocking standard. Vertical rod configurations add a bottom bolt with a 1/2-inch throw.

25 Series Dogging: Half-Turn Hex, No Threads

Half-turn hex dogging is standard on the 25 Series with no threaded dogging components anywhere in the mechanism. Traditional threaded dogging on older exit devices requires turning a threaded rod several rotations, and the threads strip or corrode over time on high-cycle doors. The Falcon 25 Series half-turn hex design eliminates all threaded components from the dogging path. One half turn clockwise dogs the device. One half turn counterclockwise releases it. No stripping. No galling. This is why the 25 Series dogging mechanism outlasts competitor devices significantly on doors dogged and released multiple times daily.

Cylinder dogging is available as an option on the 25 Series using a 1-1/8-inch mortise cylinder with standard cam. This allows the outside cylinder to dog and release the device without carrying the hex key, which is the preferred configuration for reception desks and service counters where maintenance staff routinely dog the door at opening time.

25 Series Configurations and Stile Requirements

Stile requirements vary by 25 Series configuration. Standard 25-R and 25-V configurations require a 4-1/2-inch minimum stile. The 25-C concealed vertical rod configuration requires a 3-1/2-inch minimum stile on panic versions and 4-1/2-inch minimum on fire-rated F-25-C installations. The 25-CWDC (wood door wide cable configuration) requires a 6-1/2-inch minimum stile on wood doors. Ordering a 25-V or 25-C for a door with an undersized stile produces a device that cannot be correctly mounted.

25 Series Configuration	Minimum Stile	Door Type	Fire Rating
25-R (rim)	4-1/2 inch	Metal or wood	Optional B label (F-25-R)
25-V (surface VR)	4-1/2 inch	Metal or wood	Optional B label (F-25-V); A label available on fire pair
25-C (concealed VR, metal door)	3-1/2 inch (panic); 4-1/2 inch (fire)	Metal doors	Optional B label and A label on fire pair (F-25-C)
25-CWDC (concealed VR, wood door)	6-1/2 inch	Wood doors	Optional B label (F-25-CWDC)
25-M (mortise)	4-1/2 inch	Metal or wood	Optional fire rating

25 Series Fire Ratings: A Label vs B Label

The Falcon 25 Series supports two UL fire ratings depending on the configuration. The B label (1-1/2 hour) is available on all 25 Series configurations. The A label (3-hour) is available on fire pairs (F-25-M x F-25-V or F-25-C), permitting up to 4-foot by 10-foot single doors and 8-foot by 10-foot pairs. When ordering strike replacements for fire-rated 25 Series installations, the fire strike specification matters. The F-25-C uses strike 1279 as standard and F1280 for B label applications. The F-25-V uses strike 299F for fire-rated top and 499F for fire-rated pairs with mullion.

Hex Dogging: How It Works and What Fails

Dogging is the function that holds the push bar depressed and the latch retracted, allowing the door to operate as a free-swinging door without requiring the push bar to be pressed on every pass. It is standard on the 24 and 25 Series panic versions and on the 19 Series panic version. It is never available on any fire-rated version of any series because holding a fire door latch retracted violates life safety code.

Hex dogging uses a hex key (Allen wrench) inserted into the dogging hole in the channel. On the Falcon 24 and 25 Series, the half-turn mechanism requires only a 180-degree rotation. The dogging cover plate conceals the dogging hole when not in use. This cover plate is a separately replaceable component if it is damaged or missing.

The dogging failure most technicians misdiagnose: A push bar that will not stay depressed after dogging is almost never a failed dogging mechanism. In more than 90% of field cases, the push bar returns to the undogged position because someone forgot the half-turn direction or did not complete the full half turn. Insert the hex key, depress the push bar fully, then turn the key clockwise exactly one half turn. If the key turns but the bar still does not stay depressed, check whether the installation is a fire-rated device (F-19, F-24, F-25). Fire-rated devices cannot be dogged and the mechanism is physically blocked. A fire-rated device on a non-fire-rated door is a common incorrect installation that generates repeated dogging complaints.

Electrified Options on the Falcon 24 and 25 Series

The Falcon 24 and 25 Series support a full range of electrified options for access control integration. Understanding the compatibility rules between these options prevents ordering combinations that cannot be installed together.

EL: Electric Latch Retraction

The EL option retracts the latch electrically without depressing the push bar, allowing the door to be opened from the outside by a credential reader, keypad, or building automation system. The EL solenoid operates at 24V DC and 0.34 amperes continuous duty. For 3-foot devices, the EL kit is part 650147. For 4-foot devices, it is part 650148. EL can be combined with FSA/FSE (fail safe/fail secure outside trim), DM (device monitoring), LM (latch monitoring), and AE/LK options. EL cannot be combined with ED (electric dogging), EA (exit alarm), HWEA (hard-wired exit alarm), or KOR (key override) on the same device.

Electric latch retraction serves two common use cases in commercial buildings. The first is controlled entry: a credential reader on the exterior side triggers the EL solenoid to retract the latch, allowing entry without pushing the panic bar. The second is electronic dogging during business hours: the building automation system energizes the EL solenoid for extended periods to hold the latch retracted as an alternative to mechanical hex dogging. This allows the door to operate in free-swing mode during hours and automatically re-latch when the solenoid is de-energized after hours.

EA and HWEA: Exit Alarm Options

The EA (exit alarm) option adds an audible alarm triggered when the push bar is pressed, providing delay notification or unauthorized egress alerting. The HWEA (hard-wired exit alarm) version connects to a building's wired fire alarm or security system.

The alarm circuit board replacement for pre-June 2012 HWEA assemblies is part 650335. This date boundary is critical: the alarm assembly design changed in June 2012. The 650335 board works only on pre-June 2012 assemblies. Post-June 2012 assemblies use a different alarm kit. Confirming the manufacturing date before ordering any alarm board replacement prevents a non-functional alarm installation.

KOR, LM, DM, RX: Monitoring and Override Options

KOR (key override) provides a cylinder that overrides the electrified outside trim functions without requiring electronic credentials. It is used when power failures need a mechanical fallback for authorized entry. LM (latch monitoring switch) monitors the latch bolt position and reports door open/closed status to the access control system. DM (device monitoring switch) monitors whether the push bar has been pressed. These two cannot be used on the same device because their switch mechanisms conflict. RX (request to exit switch) connects to an egress-side reader or motion sensor to signal the access control system that someone is approaching from the inside before the door opens.

The EL/EA combination that cannot be ordered: EL (electric latch retraction) and EA (exit alarm) are mutually exclusive on any Falcon 24 or 25 Series device. An EL device retracts the latch without the push bar being pressed, which would constantly trigger an EA alarm on any credential-controlled entry event. This combination is listed in the service manual as incompatible. It is also physically incompatible because both functions require access to the latch mechanism simultaneously in ways that conflict. Any specification that calls for both EL and EA on the same device requires a redesign before ordering.

How to Identify the Correct Part Before Ordering

Three pieces of information are needed before any Falcon exit device parts order.

1. Series (19, 24, or 25): Determined by the door construction and stile width as described above. The series number is typically visible on a label on the device channel or center case.

2. Configuration (R, V, C, CWDC, M): Visible from the door face. A rim device has a single latch point and no visible rod hardware on the door. A surface VR device has a visible bottom rod running down the door face to a floor strike. A concealed VR device has no visible rod hardware but two latch points (the concealed rods are inside the door stile).

3. Panic or fire-rated (prefix F-): Look for a fire label on the door or door frame. If a fire label is present, the device should be a fire-rated version. If ordering a replacement device, always match the fire rating of the original. If ordering a dogging cover plate, panic devices have a dogging hole; fire-rated devices do not.

Browse the exit device parts catalog at SecurityParts.com for all Falcon 19, 24, and 25 Series components with interactive diagrams. The Falcon hardware catalog covers exit devices alongside Falcon MA Series mortise locks and T Series cylindrical locks. Pre-order support is available at 845-935-0301 or through the contact page.

Falcon vs Von Duprin: Choosing Between the Two Exit Device Brands

Both Falcon and Von Duprin are Allegion brands. They share company ownership but serve different market positions and use different part ecosystems. Parts are not interchangeable between the two brands.

Von Duprin is the older and more widely installed brand in institutional, healthcare, and high-security government applications. The Von Duprin 98/99 Series is the dominant exit device in North American institutional buildings constructed before 2000. Von Duprin has a larger installed base and a wider parts aftermarket. Browse the complete Von Duprin parts catalog for 98/99, 22, 33/35A, 55, 75, 78, 88, and 94/95 Series devices.

Falcon is more common in mid-market commercial, retail, multi-family, and newer construction where the architectural aesthetic of the flush push pad and concealed fasteners is valued alongside ANSI Grade 1 performance at a competitive price. The 24 and 25 Series were specifically designed for the streamlined appearance requirements of modern commercial construction.

On any given building, both brands may be present: Von Duprin on older egress stairwell doors that have not been replaced, Falcon on newer tenant improvement entries and interior egress paths. SecurityParts.com stocks both, so a single order can service the complete building hardware schedule.

Why Choose Security Parts for Falcon Exit Device Parts

Series identification guidance, dogging mechanics, EL compatibility documentation, HWEA date boundary, and same-day shipping on stocked parts.

Series Identification

We document the 30-second stile width identification test that determines whether a door has a 19, 24, or 25 Series device. Wrong series orders are the most common return on exit device service calls.

EL Compatibility Rules

We document that EL is unavailable on 24 Series fire rim devices and that EL and EA cannot be combined on any device. These restrictions prevent specification errors before the order is placed.

HWEA Date Boundary

We document the June 2012 alarm board redesign and that part 650335 applies only to pre-June 2012 assemblies. Using the wrong board generation installs a non-functional alarm.

Same-Day Shipping

Most Falcon 19, 24, and 25 Series parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for pre-order compatibility support.

What Makes SecurityParts.com Different for Falcon Exit Device Parts

We document the 24 Series EL restriction on fire rim devices (F-24-R) at the part level. Facility managers upgrading access control on fire-door openings routinely order EL kits for fire rim devices without knowing the restriction. We prevent this before the order ships.
We document the EL/EA mutual exclusivity. Any specification combining both on one device requires a redesign. This is in the service manual but no parts supplier makes it accessible at the ordering stage.
We document the HWEA 650335 board date boundary with the June 2012 cutoff. This is the most common wrong-board order on alarm-equipped Falcon exit devices.
We document the half-turn hex dogging failure misdiagnosis: a push bar that returns after dogging is almost always incomplete dogging technique, not a mechanism failure. This prevents unnecessary mechanism replacements on dogging complaints.
We carry Falcon exit device parts alongside Von Duprin exit device parts, electric strike parts, LCN door closer parts, and exit alarm parts. One order services the complete egress door hardware package.
Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.

Related Parts and Products at Security Parts

A complete commercial egress door hardware package includes the exit device, door closer, and often an electric strike or exit alarm. SecurityParts.com stocks all of these for the same opening in one order.

For Von Duprin exit device parts on egress doors in the same building where Von Duprin is installed alongside Falcon hardware, browse the Von Duprin catalog. For Von Duprin electric strike parts on the door frame of any exit device installation with controlled entry, browse the electric strikes catalog. The Von Duprin 6300 electric strike is compatible with Falcon 24 and 25 Series rim devices. For commercial exit alarm parts including Von Duprin Guard-X and Detex ECL and EAX series, browse the exit alarms catalog. For LCN door closer parts on any fire-rated or controlled-closing egress door in the same building, browse the door closers catalog. For Schlage L Series and Falcon MA Series mortise lock parts on secured interior doors in the same facility, browse the mortise locks catalog.

Browse the complete all products and parts catalog to source Falcon, Von Duprin, Schlage, LCN, and Detex hardware in a single session.

Frequently Asked Questions About Falcon 19, 24 and 25 Series Exit Device Parts

What is the difference between the Falcon 19, 24 and 25 Series exit devices?

The 19 Series is narrow stile, light-to-medium duty, rim and SVR only, for doors where traffic is not consistently heavy. The 24 Series is narrow stile, heavy duty, extruded aluminum for aluminum storefront doors with stiles as narrow as 1-3/4 inches. The 25 Series is wide stile, heavy duty, for standard commercial hollow metal and wood doors with minimum 4-1/2-inch stiles. The 24 and 25 Series share the same push pad design and service manual 108004.

What is dogging on an exit device and how does hex dogging work?

Dogging holds the push bar depressed and the latch retracted so the door operates as free-swinging without pressing the bar on every pass. Hex dogging uses a hex key inserted into the dogging hole to lock the push bar down. On the Falcon 24 and 25 Series, half-turn hex dogging requires one half-turn clockwise to dog and one half-turn counterclockwise to release. No threaded components are involved, eliminating thread stripping on high-cycle doors. Fire-rated devices cannot be dogged.

What are the part numbers for the Falcon 19 Series channel and end cap?

Channel for 3-foot door is part 4107. Channel for 4-foot door is part 4108. Channel end cap kit with screws is part 650343. End cap mounting bracket is part 650320. Sex bolt mounting fastener is part 4122. Fire-rated channel cover plates are 650360 (3-foot) and 650361 (4-foot). Panic dogging channel cover is 650297 (4-foot) and 650303 (3-foot).

What are the part numbers for the Falcon 24 Series channel and end cap?

Channel for 3-foot door is part 661408. Channel for 4-foot door is part 661409. End cap kit for 1-3/4-inch door is part 650294. End cap kit for 2-1/2-inch door is part 650348. EL kit for 3-foot devices is part 650147. EL kit for 4-foot devices is part 650148. The EL solenoid is rated 24V DC at 0.34 amperes continuous duty.

What is the Falcon HWEA circuit board part number and when does it apply?

The HWEA replacement circuit board is part 650335. It applies only to alarm assemblies built before June 2012. The alarm kit was redesigned in June 2012 and the 650335 board is not compatible with post-June 2012 assemblies. Always check the date code on the existing alarm assembly before ordering any board replacement. Installing the wrong board generation results in a non-functional alarm.

What electrified options are available on the Falcon 24 and 25 Series?

Available options include EL (electric latch retraction, 24V DC 0.34A solenoid), EA (exit alarm), HWEA (hard-wired exit alarm), KOR (key override), LM (latch monitoring), DM (device monitoring), RX (request to exit), and FSA/FSE (fail safe/fail secure trim). EL cannot be combined with EA, HWEA, or KOR. DM and LM cannot be used together. EL is not available on 24 Series fire rim devices (F-24-R).

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Schlage Tubular Lock Parts: THP Latch, Privacy Rose and LT Series Complete Guide Thursday, June 25, 2026

Security Parts stocks Schlage tubular lock parts including the THP-8201 and THP-8301 passage spring latch assemblies, the THP-8219 and THP-8319 privacy latch assemblies, and the B and C design privacy roses. The THP part number encodes the backset: 82xx = 2-3/8 inch backset for 1-3/8 inch doors, 83xx = 2-3/4 inch backset for doors over 1-3/4 inch. Fire-rated versions carry the F suffix. Always confirm door thickness before ordering any THP latch assembly. The LT Series was discontinued in October 2025 and replaced by the PT Series, but THP latch and rose parts remain available for existing LT Series installations.

Tubular locks are on more interior doors in commercial buildings than any other lock type. Restrooms, private offices, utility closets, conference rooms, storage alcoves. They do not require keyed access in most of these applications. They do require reliable passage or privacy function, a latch that retracts cleanly under normal lever force, and on privacy doors, a restoring feature that prevents accidental lockouts after hours.

When a Schlage tubular lock latch fails or a privacy rose needs replacement, the THP part number system tells you exactly which component applies to which door thickness. Most wrong-part orders on tubular lock service calls come from a single error: ordering the 2-3/4 inch backset latch for a door that takes the 2-3/8 inch backset, or the reverse. This guide covers every part in the Schlage tubular lock catalog at SecurityParts.com, the functions, the fire-rated options, and the diagnostic steps that identify the correct part before you order. Browse the complete tubular lock parts catalog at SecurityParts.com.

Grade 2 ANSI/BHMA certification on the Schlage LT Series tubular lock

20 min Optional UL fire rating on the LT Series with fire-rated THP latch

1/2" Latchbolt throw on PT Series tubular latches

Oct 2025 Date Schlage LT Series discontinued, replaced by PT Series

What a Tubular Lock Is and Where It Belongs

A tubular lock uses a single bore through the door face for the entire lock chassis, with the latch assembly passing through a separate edge bore. The lock body threads directly through the door face bore. Both the inside and outside trim attach to the latch body rather than to a separate chassis housing.

This construction is lighter and less expensive than a cylindrical lock. The tradeoff is that tubular locks support fewer functions, accept fewer cylinder options, and do not achieve the same security ratings as cylindrical locks on keyed applications. In practice this is not a limitation for most tubular lock applications because the doors they serve do not require keyed locking at all.

The typical tubular lock application in a commercial building is a non-keyed interior door: a restroom, a private office where the occupant controls access by the inside privacy button, a conference room passage function, or a utility closet where entry control is not required. For any door that requires a keyed entrance function, a storeroom function, or a classroom lockdown function, browse the cylindrical lock parts catalog for the Schlage ND Series, ALX Series, or Falcon T Series instead.

The suiting advantage nobody documents clearly: The Schlage LT Series tubular lock was built on the foundational technology of the Schlage L Series mortise lock. All LT Series levers are solid brass or stainless steel and use the same lever designs, finishes, and rose sizes as the L Series mortise lock and Von Duprin exit devices. This means a building specified with L Series mortise locks on entry doors and Von Duprin exit devices on egress doors can use LT Series tubular locks on interior doors and maintain a perfectly consistent lever appearance throughout. The PT Series successor now suites with PM Series mortise locks using the same levers and roses. This suiting capability is the design reason behind the LT and PT Series product lines, and it is the most valuable single specification fact for architects and facility managers who care about visual consistency across a mixed hardware schedule.

Tubular Lock vs Cylindrical Lock: Choosing the Right Hardware

Factor	Tubular Lock (LT/PT Series)	Cylindrical Lock (ND/ALX/T Series)
Functions available	Passage, privacy, closet, storeroom (non-keyed)	24+ functions including keyed entrance, classroom, storeroom
Security level	Grade 2, not for keyed security applications	Grade 1 or 2, full security function range
Fire rating	20-minute UL rating with fire-rated THP latch (LT Series)	3-hour UL fire rating on Grade 1 cylindrical locks
Cylinder options	Limited; not suitable for IC/SFIC key systems	Conventional, FSIC, SFIC, full key system support
Lever suiting	Suites with L Series mortise and Von Duprin exit devices (LT); suites with PM Series (PT)	Suites within ND/ALX family
Door bore required	Single 2-1/8 inch face bore	2-1/8 inch face bore plus separate edge bore
Best application	Interior non-keyed passage and privacy doors	Any door requiring keyed access, Grade 1 security, or full function range

LT Series Functions: What Was Available

The Schlage LT Series offered four functions. Understanding which function is installed is the first requirement before ordering any replacement latch or trim component.

LT10: Passage

Non-keyed | Both levers always free

Both inside and outside levers always retract the latch. No locking function of any kind. Used on corridor doors, conference room entries, and any interior opening where free passage is always required. THP-8301 (2-3/4 inch) or THP-8201 (2-3/8 inch) passage latch.

LT40: Privacy

Non-keyed | Push button inside, restoring feature

Inside lever always retracts latch. Outside lever free unless locked by push button from inside rose. Turning inside lever, inserting emergency key in outside rose, or closing the door (restoring feature) unlocks outside lever. Used on restrooms, private offices, healthcare patient rooms. THP-8319 or THP-8219 privacy latch.

LT10F: Passage, Fire Rated

Non-keyed | 20-minute UL fire rating

Same operation as LT10 passage. Uses THP-8301-F fire-rated latch assembly. Required on 20-minute fire-rated door assemblies on corridor separation walls. The fire-rated latch maintains positive latching under fire conditions for the rated period.

LT40F: Privacy, Fire Rated

Non-keyed | Privacy + 20-minute UL fire rating

Privacy function identical to LT40 with fire-rated THP-8319-F or THP-8219-F latch assembly. Used on restrooms and private offices on 20-minute fire-rated corridor walls in occupancies with fire separation requirements on interior partitions.

LT Series discontinued October 2025: Schlage discontinued the LT Series in October 2025, replaced by the PT Series. If you are maintaining an existing LT Series installation, THP latch assemblies and privacy roses remain available for ongoing service. If specifying new installations, the PT Series is the current Schlage tubular lock offering. SecurityParts.com stocks THP parts for existing LT Series service needs.

The THP Part Number System: How to Read It

Every Schlage LT Series latch assembly has a THP part number that encodes the function type and backset in its digits. Understanding this system eliminates the most common wrong-part order on tubular lock service calls.

Part Number	Function	Backset	Faceplate	Door Thickness	Fire Rated
THP-8201-CH	Passage (spring latch)	2-3/8 inch	1" x 2-1/4" square	Typical for 1-3/8" doors	No
THP-8201-CH-F	Passage (spring latch)	2-3/8 inch	1" x 2-1/4" square	Typical for 1-3/8" doors	Yes, UL 3hr
THP-8301-CH	Passage (spring latch)	2-3/4 inch	1-1/8" x 2-1/4" square	Typical for >1-3/4" doors	No
THP-8301-CH-F	Passage (spring latch)	2-3/4 inch	1-1/8" x 2-1/4" square	Typical for >1-3/4" doors	Yes, UL 3hr
THP-8219-CH	Privacy latch	2-3/8 inch	1" x 2-1/4" square	Typical for 1-3/8" doors	No
THP-8219-CH-F	Privacy latch	2-3/8 inch	1" x 2-1/4" square	Typical for 1-3/8" doors	Yes, UL 3hr
THP-8319-CH	Privacy latch	2-3/4 inch	1-1/8" x 2-1/4" square	Typical for >1-3/4" doors	No
THP-8319-CH-F	Privacy latch	2-3/4 inch	1-1/8" x 2-1/4" square	Typical for >1-3/4" doors	Yes, UL 3hr

The backset identification rule: The second digit pair in the THP number tells you the backset. 82xx = 2-3/8 inch backset (short). 83xx = 2-3/4 inch backset (long). The third digit pair tells you the latch type. xx01 = passage spring latch. xx19 = privacy latch. So THP-8219 = 2-3/8 inch privacy latch for thin doors. THP-8319 = 2-3/4 inch privacy latch for standard commercial doors. This four-minute rule eliminates the most common THP wrong-part order.

Every Replaceable Component in the Schlage LT Series

Spring Latch Assembly (THP-8201 and THP-8301)

The spring latch is the beveled bolt that automatically extends when the door closes and retracts when the inside or outside lever is turned. On the LT Series passage function, both inside and outside levers always retract the latch freely with no locking mechanism involved.

Spring latch failure presents as a latch that does not retract when the lever is turned, a latch that does not spring back to the extended position after retraction, or a latch that binds in the faceplate and requires excessive lever force to retract. A latch that binds in the faceplate is often a door alignment problem rather than a latch failure: the door has settled and the latch tip is contacting the strike plate edge rather than the bolt pocket. Check strike alignment before replacing a latch that binds on closing.

Each THP spring latch assembly includes the latch body, faceplate, and mounting screws in the package. No additional hardware is required for a direct replacement on a door with matching backset.

Privacy Latch Assembly (THP-8219 and THP-8319)

The privacy latch assembly is more complex than the spring latch. In addition to the spring latch body, it includes the internal locking pin mechanism that engages when the push button on the inside rose is pressed, locking the outside lever. It also includes the restoring mechanism that releases the outside lever when the door closes.

Privacy latch failure presents as a latch that does not lock the outside lever when the push button is pressed, a push button that sticks in the locked or unlocked position, or a latch that does not restore to unlocked on door closing. The restoring mechanism is a cam component inside the latch body that detects door closing through the latch tip contact with the strike. If the door has a strike plate that is positioned so the latch tip does not fully contact the strike face on closing, the restoring function may not activate reliably. Verify strike plate position before diagnosing internal restoring mechanism failure.

Privacy Rose: B Design (Part 09-486) and C Design (Part 09-459)

The privacy rose is the cover plate on the inside face of the LT40 privacy door that contains the push button for locking the outside lever and the emergency access hole for unlocking from outside with a pin or coin. SecurityParts.com stocks two privacy rose designs for the LT Series:

Part 09-459 (C design privacy rose): The C design rose uses a rounder, more contemporary profile. Available in multiple finishes to match existing LT Series hardware.

Part 09-486 (B design privacy rose): The B design rose uses a slightly different profile. Finish-specific ordering required.

Privacy roses are finish-specific. Always confirm the finish code before ordering a replacement rose. The most common finish codes for LT Series hardware are 626 (satin chrome), 619 (satin nickel), 622 (matte black), and 625 (bright chrome). Installing a rose in the wrong finish leaves a visible mismatch on the interior door face that requires a second return and reorder.

The emergency access function nobody fully explains: Every Schlage LT40 privacy rose has a small hole on the outside face, typically near the center or at the bottom depending on the rose design. This hole accepts a thin emergency access pin or a straightened paper clip. Pressing the pin through the hole releases the privacy button mechanism and unlocks the outside lever without any key. This is the standard emergency release for any room where someone has become incapacitated, where a child is locked inside, or where a maintenance operation requires access to a locked room without the occupant being present. The emergency pin is not a security bypass. Anyone standing outside the door can use it. Privacy locks are privacy devices, not security locks. Any door requiring actual keyed security needs a cylindrical lock, not a tubular privacy function.

Strike Plate

The LT Series uses a T-strike (T-shaped strike plate) as the default, not the ANSI curved lip strike used on cylindrical locks and deadbolts. The T-strike covers the latchbolt pocket in the door frame with a lip configuration that guides the spring latch tip into the pocket on every door close.

Strike options for the LT Series include the T-strike square corner (10-001 series, specify lip length from 1 inch to 2 inches), T-strike round corner (10-004, 1/4 inch radius, 1-1/8 inch lip length), and ANSI strike (10-025 series, 1-1/4 inch by 4-7/8 inch, specify lip length). The T-strike is typically used when the door frame has a standard tubular lock prep. The ANSI strike is used when the door frame prep matches the ANSI standard for cylindrical locks and the installer wants to use the same frame prep for both the tubular lock and any adjacent hardware.

Levers and Solid Brass Construction

The LT Series levers are manufactured from solid brass or solid stainless steel, not pressure cast zinc. This is the construction distinction that separates the LT Series from most competitor tubular locks and from the Schlage S Series and other economy tubular lines. Solid brass levers have a heavier feel, longer wear life, and a more premium finish durability than cast zinc levers.

The LT Series levers move both up and down for a bidirectional operational experience that matches the Schlage L Series mortise lock levers and Von Duprin exit devices. Inside and outside levers operate independently, allowing the inside lever to spring back without affecting the outside lever position. This independent operation creates a quieter, less institutional operational character compared to coupled-lever designs where both levers move together.

Fire-Rated Tubular Locks: When Are They Required

Fire-rated tubular locks are required when the door is part of a UL-listed fire-rated assembly. In commercial buildings, the most common application for fire-rated tubular locks is on restroom doors, private office doors, and utility closet doors in corridors or exit passageways that have a fire separation requirement.

Interior partition walls between office tenant spaces and building corridors often require a fire resistance rating. The doors in these walls must use hardware that is listed for the fire rating of the wall assembly. A 20-minute fire-rated door assembly is the most common rating level in interior partition applications. The Schlage LT Series with THP-F fire-rated latch achieves this 20-minute UL rating.

The fire-rated latch substitution that invalidates the fire assembly: Installing a non-fire-rated THP latch (no F suffix) on a door that is part of a fire-rated assembly voids the UL listing of that assembly. The fire door is technically unlisted from the moment the non-fire-rated latch is installed. This is a common maintenance error when the replacement part is ordered by description (spring latch, 2-3/4 inch backset) rather than by the complete part number including the F suffix. Always check for a fire label on the door before ordering any replacement latch. If the door has a fire label, order the F-suffix version of the THP latch.

Schlage PT Series: The Current Replacement for LT Series

The Schlage PT Series became the replacement for the discontinued LT Series after October 2025. For facility managers maintaining mixed-generation buildings, understanding the differences matters for ongoing parts planning.

PT Series vs LT Series: Key Differences

The PT Series is purpose-built for four functions (passage, privacy, passage fire-rated, privacy fire-rated) with 10 lever styles and 6 finishes. The LT Series offered 31 lever designs and 14 finishes, which is why the LT Series was specified on premium projects requiring extensive design flexibility. The PT Series reduces the choice set in exchange for a more cost-competitive price point.

The PT Series uses a stainless steel latchbolt with a 1/2 inch throw. The snap-on wrought brass rose eliminates exposed rose screws for a cleaner finished appearance on the door face. The PT Series suites with the PM Series mortise locks using shared levers and rose designs, following the same suiting strategy as the LT and L Series relationship.

For new installations on premium projects requiring extensive lever design selection and L Series suiting, the LT Series parts available at SecurityParts.com support existing installations. For new installations where the PT Series sufficient design selection meets the specification, the PT Series is the current Schlage offering.

Parts Availability for Existing LT Series Installations

SecurityParts.com stocks THP latch assemblies and privacy roses for existing LT Series installations. A building specified with LT Series hardware in 2018 or 2022 will need THP latches and privacy roses for the next 15 to 20 years of normal service. The discontinuation of the LT Series as a new product does not affect the availability of replacement parts for installed units. Browse the tubular lock parts catalog for current stocking status on all THP assemblies.

How to Identify the Correct THP Part Before Ordering

Two measurements and one visual check are all that is needed before any THP parts order.

1. Measure the backset. The backset is the distance from the center of the door bore to the edge of the door face. On a standard commercial hollow metal or solid core wood door, measure from the center of the door handle hole to the door edge. If this dimension is approximately 2-3/8 inches, order THP-82xx. If approximately 2-3/4 inches, order THP-83xx. Do not guess. A THP latch with the wrong backset will not reach the strike properly and the door will not latch correctly.

2. Identify the function (passage or privacy). Does the current installation have a push button on the inside rose? If yes, it is a privacy function. Order THP-8219 or THP-8319. If the inside and outside levers both always retract the latch freely with no button, it is a passage function. Order THP-8201 or THP-8301.

3. Check the door for a fire label. Look at the top or hinge edge of the door for a UL fire label. If present, order the F-suffix version of the correct THP latch. If no label is visible, the standard non-F version is appropriate.

Browse the Schlage tubular lock parts catalog at SecurityParts.com with part numbers and diagrams for every THP assembly. For the complete Schlage hardware range including LT Series tubular locks, ND Series cylindrical locks, L Series mortise locks, and CS210 interconnected locks, browse the Schlage commercial hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

What Fails First on Schlage Tubular Locks

1. Spring latch assembly. Latch spring fatigue is the primary failure mode on high-cycle doors. The latch bolt does not return to the extended position after retraction, which means the door does not latch on closing. A door that requires a push to close and latch is always a spring latch issue. Replace the full THP assembly, not just the spring.

2. Privacy push button mechanism. On LT40 privacy doors, the push button or the internal locking pin can wear or bind after years of use. The symptom is a push button that requires excessive force to depress, does not stay in the locked position, or pops out immediately without locking the outside lever. The privacy latch assembly (THP-8219 or THP-8319) replaces the complete mechanism.

3. Restoring mechanism failure. The restoring feature that unlocks the outside lever on door closing can fail to actuate if the latch tip does not fully contact the strike plate on closing (strike misalignment) or if the internal restoring cam wears. Always check strike alignment before assuming the restoring cam has failed. Adjusting the strike position often restores this function without any parts replacement.

4. Rose assembly. The inside privacy rose sustains the most cosmetic wear of any component because it receives direct hand contact on every entry and exit. Finish wear and physical cracking from abuse require rose replacement. Always confirm the design (B or C) and finish code before ordering.

5. Lever assembly. The solid brass levers on the LT Series are more durable than cast zinc alternatives, but they can still bend or crack under deliberate physical abuse. Lever replacement requires confirming the specific lever design from the 31 LT Series options and the finish code.

Why Choose SecurityParts.com for Schlage Tubular Lock Parts

THP part number guidance, backset identification, fire-rated latch documentation, and same-day shipping on stocked components.

THP Part Number Guidance

We document the backset-to-part-number relationship so you order THP-8219 vs THP-8319 correctly the first time. The most common tubular lock wrong-part order is a wrong-backset latch.

Fire-Rated Latch Documentation

We document when the F-suffix fire-rated latch is required. Installing a non-fire-rated latch on a fire-labeled door voids the UL assembly listing. We flag this before the order ships.

LT Series Service Support

LT Series discontinued October 2025 but THP parts available for existing installations. We stock these for the ongoing service life of LT Series hardware already in service.

Same-Day Shipping

Most THP latch and rose parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for backset or fire-rating confirmation.

What Makes SecurityParts.com Different for Tubular Lock Parts

We document the THP digit-to-backset decoding rule (82xx = 2-3/8 inch, 83xx = 2-3/4 inch) that eliminates the most common wrong-part order. No other supplier explains this in buyer-facing content.
We document the privacy restoring feature failure diagnostic: check strike alignment before assuming the restoring cam has failed. Most restoring failures are strike position problems, not internal mechanism failures.
We explain that the emergency access pin function on the privacy rose is a privacy release, not a security bypass, and that any door requiring actual keyed security needs a cylindrical lock. This prevents the misspecification of privacy tubular locks on security-critical doors.
We document the LT Series suiting with L Series mortise locks and Von Duprin exit devices. The PT Series suiting with PM Series is also documented. Specifiers who do not know this miss the primary reason these series exist.
We carry tubular lock parts alongside cylindrical lock parts, mortise lock parts, interconnected lock parts, and door closer parts. One order covers the full building hardware service call.
Free shipping on orders over $450. Same-day shipping on stocked parts from US warehouses.

Related Parts and Products at SecurityParts.com

Tubular locks are typically part of a complete interior door hardware package. The same building that uses LT or PT Series tubular locks on restroom and corridor doors also uses cylindrical locks on offices, mortise locks on entries, and door closers on fire-rated corridor doors.

For Schlage ND Series, ALX Series, and Falcon T Series cylindrical lock parts on keyed office doors and storerooms in the same facility, browse the cylindrical locks catalog. For Schlage L Series and Falcon MA Series mortise lock parts on main entry doors and secured offices, browse the mortise locks catalog. For Schlage CS210 interconnected lock parts on dwelling unit entry doors requiring single-motion egress, browse the interconnected locks catalog. For Schlage B Series deadbolt parts on secondary doors, browse the deadbolts catalog. For LCN door closer parts on fire-rated corridor doors in the same building, browse the door closers catalog. For Von Duprin and Falcon exit device parts on building egress doors, browse the commercial exit devices catalog.

Browse the complete all products and parts catalog to source Schlage, Von Duprin, LCN, Falcon, and Detex hardware in a single session.

Frequently Asked Questions About Schlage Tubular Lock Parts

What is the difference between a Schlage THP-8201 and THP-8301 spring latch?

Both are passage spring latch assemblies for the Schlage LT Series. The THP-8201 has a 2-3/8 inch backset and 1 inch by 2-1/4 inch faceplate for 1-3/8 inch thick doors. The THP-8301 has a 2-3/4 inch backset and 1-1/8 inch by 2-1/4 inch faceplate for doors thicker than 1-3/4 inches. Always measure the backset from the center of the door bore to the door edge before ordering.

What is the difference between the THP-8219 and THP-8319 privacy latch?

Both are privacy latch assemblies with a push-button locking mechanism and restoring feature. The THP-8219 has a 2-3/8 inch backset for 1-3/8 inch doors. The THP-8319 has a 2-3/4 inch backset for doors thicker than 1-3/4 inches. Privacy latches include a restoring feature that automatically unlocks the outside lever when the door closes, preventing accidental lockouts.

What is the fire-rated version of the Schlage THP latch and when is it required?

Fire-rated THP latches carry an F suffix in the part number (THP-8201-CH-F, THP-8301-CH-F, THP-8219-CH-F, THP-8319-CH-F). They are required on any door with a UL fire label. The LT Series with fire-rated THP latch achieves a 20-minute UL fire door rating. Installing a non-fire-rated latch on a fire-labeled door voids the UL assembly listing. Always check the door for a fire label before ordering any replacement latch.

What is the privacy restoring feature on the Schlage LT40 and why does it matter?

The restoring feature automatically unlocks the outside lever when the door closes after being locked with the inside push button. This prevents accidental lockouts where a door is locked from inside with no one available to unlock it from outside. The restoring function activates through the latch tip contacting the strike plate on door closing. If the restoring feature fails to activate, check strike alignment before assuming the internal mechanism has failed.

What is the difference between a tubular lock and a cylindrical lock?

A tubular lock uses a single bore through the door and is lighter duty, supporting passage and privacy functions without keyed locking. A cylindrical lock uses a separate chassis bore and edge bore, supports 24-plus functions including keyed entrance, storeroom, and classroom locks, achieves higher UL fire ratings, and accepts FSIC and SFIC interchangeable core cylinders. Use tubular on interior non-keyed doors. Use cylindrical on any door requiring a keyed function or Grade 1 security.

What Schlage tubular lock series replaced the LT Series after October 2025?

The PT Series replaced the LT Series in October 2025. The PT Series offers 4 functions, 10 lever styles in 6 finishes, stainless steel latchbolt with 1/2 inch throw, snap-on wrought brass rose without exposed screws, and suiting with PM Series mortise locks. For existing LT Series installations, THP latch and rose parts remain available at SecurityParts.com for ongoing maintenance and service needs.

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Schlage CS210 Interconnected Lock Parts: CS200 Series Complete Guide Wednesday, June 24, 2026

The Schlage CS210 is the CS200 Series Grade 2 interconnected lock. It combines a cylindrical latch and deadbolt in one assembly so turning the inside lever retracts both simultaneously in one motion, meeting IBC and NFPA 101 single-motion egress requirements. The main replacement parts are the lever kit (06-242), rose (08-029), inside escutcheon (Camelot or Plymouth), outside housing (B500 commercial or B60 residential), strikes, and the interconnect assembly. The crimp-to-snap rose transition in August 2015 is the most important fact for parts ordering: pre-2015 units with crimp-on roses require the outside chassis assembly (F206-496) when changing levers or roses.

Interconnected locks are on more apartment building, hotel, dormitory, and assisted living entry doors than any other lock type in the multifamily residential sector. They are specified because they solve a specific problem that no other single hardware component solves: providing both a spring latch for automatic latching and a deadbolt for security, while allowing a single inside lever motion to retract both simultaneously for code-compliant egress.

The Schlage CS210 is the most widely installed commercial interconnected lock in North America. It carries ANSI/BHMA Grade 2 certification, UL 3-hour fire door listing, and a lifetime limited mechanical warranty. When one fails or requires a lever change, rose replacement, or escutcheon update, the rose generation transition in 2015 creates a parts compatibility issue that catches most technicians off guard. This guide covers every component, that transition, the code context, and exactly how to order. Browse the complete interconnected lock parts catalog at SecurityParts.com for CS210 diagrams and components.

Grade 2 ANSI/BHMA A156.12 certification on the Schlage CS210

UL 3hr Fire door listing on the CS210 with conventional cylinder

18 Lever designs available on the CS200 Series

Aug 2015 Crimp-on to snap-on rose transition date on the CS210

What an Interconnected Lock Is and Why It Exists

An interconnected lock is a single hardware assembly that combines two separate locking mechanisms, a spring latch and a deadbolt, with a mechanical interconnection that allows both to retract simultaneously when the inside lever is turned. From the outside, the lock operates as a standard keyed deadbolt entry. From the inside, turning the lever once retracts both the deadbolt and the latch in a single motion, allowing free exit without any separate deadbolt thumb turn operation.

This single-motion egress capability is the entire reason the category exists. IBC Section 1010.1.9 and NFPA 101 both require that doors in a means of egress unlatch with no more than one releasing motion. For most commercial occupancies, installing a separate cylindrical latch and a separate deadbolt creates a two-motion exit requirement that violates this code, because the occupant must turn the deadbolt thumb turn and then turn the lever separately to exit.

The interconnected lock solves this by making the inside lever turn the only operation needed for exit. The deadbolt and latch both retract together. The door opens. One motion. Code compliant.

The code nuance nobody explains fully: For residential Group R dwelling units (apartments, hotel rooms, dormitory rooms) with an occupant load of 10 or less, both IBC and NFPA 101 allow a separate deadbolt in addition to a latchset, provided the deadbolt can be released from the inside without a key or tool. This is why separate deadbolts are common on apartment doors in most jurisdictions. However, some states and local jurisdictions have adopted stricter requirements that mandate one-motion egress even on Group R dwelling unit entry doors. In those jurisdictions, a separate deadbolt with a separate latchset is not compliant, and an interconnected lock or mortise lock is the only hardware solution for a door requiring both a latch and deadbolt. Always verify the local code before specifying hardware on any multi-family project.

Where the Schlage CS210 Is Specified

The CS210 appears most frequently on dwelling unit entry doors in commercial multi-family buildings: apartment complexes, condominiums, dormitories, extended-stay hotels, and assisted living facilities. The specific application logic that drives the CS210 specification is the need for resident-facing security with single-motion egress in a commercial-grade fire-rated assembly.

Assisted living facilities are a particularly important distinction. Assisted living units are classified as Residential Board and Care occupancies under NFPA 101, not standard residential occupancies. The residential dwelling unit exception that allows a separate deadbolt does not apply to assisted living units. On assisted living dwelling unit entry doors, an interconnected lock or mortise lock is required in most jurisdictions because a separate deadbolt and latchset do not comply with one-motion egress for this occupancy type.

For institutional dormitories, hotel properties, and any jurisdiction with accessible or adaptable unit requirements, interconnected locks are often specifically mandated by local code supplements to the IBC. Massachusetts 521 CMR, for example, explicitly requires interconnected locks on accessible and adaptable dwelling units.

CS210 vs Separate Deadbolt vs Mortise Lock: Which One Fits the Opening

Schlage CS210 Interconnected

Grade 2 | Single-Motion Egress

One lever motion retracts latch and deadbolt simultaneously. Required on dwelling unit doors where one-motion egress is mandated. Standard bore prep (2-1/8 inch crossbore). Grade 2. 18 lever styles. Adjustable for 4 or 5-1/2 inch center-to-center. UL 3-hour fire listed. Lifetime limited warranty.

Separate Deadbolt + Latchset

Grade 1 or 2 | Two Motions Inside

Allowed on Group R dwelling units (occupant load 10 or less) where local code permits. Requires two inside motions to exit when deadbolt is thrown. Not compliant on most commercial occupancy doors. Lower installed cost. Higher security grade options available. Acceptable for most apartment and hotel doors in most jurisdictions.

Schlage L Series Mortise Lock

Grade 1 | Integrated in Single Case

Latch and deadbolt integrated in a single mortise case. Single lever retracts both when outside is locked in most functions. Grade 1. 40-plus functions. Best for high-security institutional dwelling unit doors where Grade 1 strength is required. Higher cost and more complex installation than the CS210.

Every Component in the Schlage CS210

Outside Housing Assembly: B500 vs B60

The CS210 offers two outside deadbolt housing configurations. This is the first specification decision and it determines the security level of the entire assembly.

CS210-B500 (commercial spin ring): The B500 outside housing includes a free-spinning cylinder collar that resists wrenching and prying. It also includes a removeable security shield that protects the deadbolt from ice-pick attacks through the door face. These are the same security features found in the Schlage B600 Series Grade 1 deadbolt. The B500 housing is the correct specification for any commercial or institutional application where physical attack resistance matters. The cylinder collar spins freely under wrench pressure rather than providing purchase for torque.

CS210-B60 (residential spin ring): The B60 housing is the residential version for multi-family buildings where the aesthetic and cost profile of a residential deadbolt is appropriate and the additional attack resistance features of the B500 are not required by the specification.

Outside housing and rose compatibility warning: The outside housing assembly, the rose, and the cylinder collar are not universally interchangeable between configurations. When ordering a replacement outside housing assembly, always confirm whether the existing installation uses the B500 or B60 configuration before ordering. Substituting the wrong housing changes both the security level and potentially the aesthetic of the finished installation.

Lever Kit (Part 06-242)

The CS210 lever kit (part 06-242) includes two matching levers, one outside and one inside. The CS200 Series offers 18 lever designs allowing the CS210 to match the aesthetic of other Schlage hardware throughout the same building. Lever designs are available in seven finishes including satin chrome (626), brushed nickel (619), matte black, polished brass (605), aged bronze, and others.

Lever replacement is needed when a lever is physically damaged, when a finish change is required after a renovation, or when a lever becomes stiff or fails to return to horizontal due to internal spring fatigue. The lever kit includes both levers, which keeps inside and outside matching during replacement. Always confirm the finish code before ordering a replacement lever kit.

Rose (Part 08-029)

The rose is the circular cover plate visible on the door face around the outside lever and cylinder area. The CS210 offers two outside rose designs: Plymouth and Saturn. The rose is finish-specific. Part 08-029 is the standard rose for snap-on rose installations (August 2015 and later). For crimp-on rose installations (pre-August 2015), see the crimp-to-snap section below before ordering any rose replacement.

Inside Escutcheon: Camelot (CAM) and Plymouth (PLY) Designs

The inside escutcheon is the decorative plate on the interior face that covers the inside chassis and positions the inside lever and thumb-turn plate. The CS210 offers two inside escutcheon designs: Camelot (CAM) and Plymouth (PLY). Both designs are available in the same seven finishes as the levers.

The inside escutcheon houses the adjustable thumb-turn plate assembly that supports both the 4-inch and 5-1/2-inch center-to-center door prep conversions. The escutcheon plate adjustment is a field modification; no additional parts are ordered for a center-to-center conversion. If the escutcheon itself is damaged or a design change is required, the escutcheon is an individually replaceable component.

Interconnect Assembly

The interconnect assembly is the internal mechanism that links the inside lever to both the deadbolt and latch, enabling the simultaneous retraction in one motion. This is the component that makes an interconnected lock different from a standard cylindrical lock with a separate deadbolt.

The interconnect assembly carries the load of both the deadbolt spring and the latch spring when the inside lever is turned. This combined spring load requires slightly more torque to operate than either a latch-only or deadbolt-only lock. The design intent is that a healthy adult requires no additional force beyond a normal lever turn. However, the combined spring load can become problematic for elderly, infirm, or physically limited occupants on doors where both springs are at the high end of their adjustment range. If a CS210 installation is reporting difficulty operating the lever, check that neither spring is adjusted beyond the standard setting before assuming the interconnect assembly has failed.

Interconnect assembly replacement is required when the inside lever turns but only one of the two mechanisms (latch or deadbolt) retracts, when the interconnect binding causes the lever to feel mechanically stiff at a specific point in its rotation arc, or when the assembly fails to fully return to the latched position after a lever release. Center-to-center conversion (4 inch to 5-1/2 inch or reverse) is made by a field modification to the interconnect assembly without requiring a replacement part.

Strike Plate (Part 10-109 and 10-121 Combination Strikes)

The CS210 uses a combination strike that includes both a deadbolt strike and a deadlatch strike in a single plate assembly. Both strikes must be correctly positioned in the door frame for the lock to operate without binding. The CS210 standard combination strike is part 10-109. The 10-121 is an alternate combination strike. A T-strike (1-5/8 inch by 2-1/4 inch) is also available for the deadbolt portion.

Strike alignment is the most common cause of a CS210 installation that feels stiff or incomplete on either the deadbolt throw or the latch engagement. Because the CS210 operates two mechanisms simultaneously, even minor vertical misalignment of either strike pocket creates binding that feels like internal mechanism failure. When a CS210 is reported to be stiff or incomplete in its operation, verify both strike alignments before diagnosing internal components.

The CS210 also includes a metal wood frame reinforcer using 3-inch screws that anchor into the door frame stud for kick-in resistance. This is the same dust box concept as the B Series deadbolt and its presence significantly increases the resistance of the frame to forced entry. It should always be installed and is not optional on any security-sensitive application.

Deadbolt Strike (Part 10-116)

The deadbolt-only strike (part 10-116) is a round corner strike, 1-1/8 inch by 2-3/4 inch, no lip. This is used when the deadbolt and latch have separate frame preps rather than a combined pocket. Always confirm whether the installation uses a combination strike or separate strikes before ordering replacement hardware.

The Crimp-On to Snap-On Rose Transition: The Most Important CS210 Service Fact

In August 2015, Schlage transitioned the CS210 from crimp-on roses to snap-on roses. This transition is completely undocumented in most parts supplier catalogs and is the single most common cause of wrong-part returns on CS210 service calls.

How to Identify Which Generation Your Lock Is

Remove the outside rose from the door face. Examine the base of the rose where it meets the door surface. Snap-on roses have retention dimples at the base. Crimp-on roses do not have these dimples and have a smooth or rolled edge at the base instead. If you are not certain which generation is installed, this physical check takes under two minutes and prevents an incorrect parts order.

What Happens If You Order the Wrong Generation

The lever kit (06-242) and rose (08-029) designed for snap-on rose installations cannot be used on a crimp-on rose chassis. The retention mechanism is physically different and the lever will not seat correctly. If you have a pre-August 2015 installation with a crimp-on rose and order the current lever kit without also updating the outside chassis, the parts will not function correctly after installation.

The Correct Crimp-On to Snap-On Upgrade Parts

For a pre-August 2015 crimp-on rose installation that needs a lever or rose replacement, order all four of these components together:

Part Number	Description	Required For
06-242	Lever kit (two levers)	New levers, snap-on compatible
08-029	Outside rose (Plymouth or Saturn)	New snap-on rose
A501-945	Reinforcement ring	Supports snap-on rose seating
F206-496	Outside chassis assembly	Updated chassis for snap-on compatibility

For post-August 2015 snap-on rose installations: Only order the lever kit (06-242) and rose (08-029) when changing levers or roses. The existing chassis and reinforcement ring are already compatible. Ordering the full four-part update kit for a snap-on installation adds unnecessary cost without functional benefit.

Center-to-Center Door Prep Conversion: Field Modification Without Parts

The CS210 adjustable escutcheon plate supports both 4-inch and 5-1/2-inch center-to-center door preparations. This is the dimension between the centerline of the deadbolt bore and the centerline of the cylindrical latch bore on the door face.

The conversion is made entirely in the field by modifying the interconnect assembly position inside the escutcheon plate. No additional parts are required and no replacement components need to be ordered. The procedure is:

For 4-inch center-to-center: Remove two screws and the plate from the escutcheon assembly. Position the thumb-turn assembly with the thumb turn toward the bottom of the thumb-turn escutcheon plate.

For 5-1/2-inch center-to-center: Keep the plate in place with the two screws. The thumb-turn remains in its standard position.

This field adjustability is the design feature that eliminates job-site surprises when the existing door prep does not match a specific standard. A building with mixed 4-inch and 5-1/2-inch door preps can use the same CS210 lock on every unit door without ordering two different lock configurations.

CS210 Technical Specifications

Specification	Detail
ANSI/BHMA certification	A156.12-2013, Grade 2 operational and security
Fire door listing	UL 3-hour fire door (with conventional cylinder)
SFIC cylinder fire listing	Grade 3 security (with SFIC interchangeable core)
Function	CS210 entrance, single locking. Inside lever retracts both latch and deadbolt.
Crossbore	2-1/8 inch standard
Center-to-center	4 inch or 5-1/2 inch (field adjustable)
Door thickness	1-3/8 to 1-3/4 inch standard; 1-3/4 to 2 inch metal door
Backset	Adjustable 2-3/8 or 2-3/4 inch
Latch throw	1 inch
Latch faceplate	1 inch by 2-1/4 inch (standard door); 1-1/8 inch square corner (metal door)
Deadbolt strike	1-5/8 inch by 2-1/4 inch T-strike standard
Cylinder	6-pin, C keyway standard. Everest 29 keyway available.
Handing	Reversible in field
Levers	18 designs in 7 finishes
Escutcheon options	Camelot (CAM) and Plymouth (PLY) inside designs
Rose options	Plymouth and Saturn outside designs
Outside housing	B500 commercial spin ring or B60 residential spin ring
Warranty	Lifetime limited mechanical and finish

Parts That Fail First on the Schlage CS210

Based on actual field service frequency, here is the realistic replacement sequence for CS210 components on high-traffic multi-family installations.

1. Levers. The outside lever takes physical contact on every door entry and exit. Finish wear is the most common cosmetic issue. Physical damage from cart impact or door abuse is the most common functional issue. The lever kit (06-242) replaces both inside and outside levers. Always check the rose generation before ordering (crimp vs snap as described above).

2. Strike plate alignment. This is not a parts failure but a maintenance item. Door settling in multi-family buildings causes progressive strike misalignment that shows up as a stiff deadbolt throw, incomplete latch engagement, or a lever that requires more force than normal. Check both strike alignments before diagnosing internal components. Re-securing loose strike screws or adjusting the strike position resolves most CS210 stiffness complaints without any parts replacement.

3. Cylinder. The 6-pin C keyway cylinder in the CS210 wears at the same rate as any commercial cylinder under high-cycle use. Key stiffness or a key that operates inconsistently indicates cylinder wear. As with all Schlage cylinders, use only graphite or silicone lubricant. Oil-based lubricants accelerate pin stack contamination and require cylinder replacement.

4. Inside escutcheon assembly. The inside escutcheon is subject to cosmetic damage on unit entry doors where residents are frequently carrying items. A cracked escutcheon plate or a finish that has worn through requires replacement as a complete escutcheon assembly. Confirm the Camelot or Plymouth design before ordering.

5. Interconnect assembly. The internal interconnect mechanism has the longest service life of any component in the CS210 because it is protected inside the door and does not receive direct physical contact. Interconnect failure appears as a lever that retracts one mechanism but not the other, or as an inconsistent combined retraction. Full interconnect replacement is required when this occurs.

Code Compliance: Interconnected Lock vs Separate Deadbolt on Dwelling Unit Doors

The code question that drives most CS210 specifications is whether a separate deadbolt is allowed on a dwelling unit entry door or whether an interconnected lock is required.

Where Separate Deadbolts Are Allowed

IBC Section 1010.1.9 and NFPA 101 both include an exception for Group R residential dwelling units with an occupant load of 10 or less. On these doors, a separate nightlatch, deadbolt, or security chain is permitted in addition to the latching hardware, provided the separate device can be released from the inside without a key or tool. A thumbturn-operated single cylinder deadbolt meets this requirement.

This exception applies to most apartments, condominiums, dormitory rooms, hotel rooms, and similar units. It is the reason separate deadbolts are common on apartment doors throughout the United States. In these jurisdictions, the CS210 is a premium specification option, not a code requirement.

Where Interconnected Locks Are Required

Several situations eliminate the separate deadbolt exception and require one-motion egress on dwelling unit entry doors. The first is when the local jurisdiction has adopted stricter requirements than the model codes. The second is for accessible or adaptable dwelling units in jurisdictions following accessibility standards that mandate one-motion egress hardware. The third is for assisted living and residential board and care facilities where the NFPA 101 residential occupancy exception does not apply. In all three situations, an interconnected lock or mortise lock is the only code-compliant hardware solution for a door requiring both a latch and a deadbolt.

The Assisted Living specification trap: Assisted living facilities are regularly misspecified with separate deadbolts because the word "residential" in their NFPA 101 classification (Residential Board and Care) is misread as qualifying for the residential dwelling unit exception. It does not. The residential dwelling unit exception in NFPA 101 applies to apartment buildings, rooming houses, hotels, motels, dormitories, and 1-2 family dwellings. Assisted living facilities are Board and Care occupancies, a distinct classification, and the one-motion egress requirement applies fully. Any separate deadbolt on an assisted living unit entry door in a jurisdiction enforcing NFPA 101 is non-compliant hardware.

How to Order CS210 Parts Without a Return

Four pieces of information are required before any CS210 parts order:

1. Rose generation (crimp or snap): This is the most important check. Remove the outside rose and look for retention dimples at the base. Dimples = snap-on (August 2015 or later). No dimples = crimp-on (pre-August 2015). If the lock is pre-2015, the outside chassis (F206-496) must be ordered along with the lever kit and rose.

2. Outside housing type (B500 or B60): The B500 has a free-spinning cylinder collar and security shield. The B60 does not. This is visible without disassembly: grip the exterior cylinder collar and attempt to rotate it. Free spin = B500. Fixed = B60.

3. Inside escutcheon design (Camelot or Plymouth): The Camelot design has a more traditional rectangular profile. The Plymouth has a more contemporary rounded shape. Both are visible on the interior door face without disassembly.

4. Finish code: Visible on the hardware face. Common CS210 finishes include 626 (satin chrome), 619 (satin nickel), 622 (matte black), 625 (bright chrome), and 605 (polished brass). All replacement components are finish-specific.

Browse the complete CS210 parts catalog at SecurityParts.com. For the full Schlage commercial hardware range including the CS210, ND Series, L Series, and B Series, browse the Schlage commercial hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for Schlage CS210 Parts

Rose generation identification, crimp-to-snap conversion guidance, code context, and same-day shipping on stocked components.

Rose Generation Guidance

We document the crimp-to-snap rose transition and what it means for parts ordering. The four-part upgrade kit for pre-2015 units is documented before the order is placed, not after the wrong part arrives.

Code Context Included

We explain when an interconnected lock is required vs when a separate deadbolt is allowed. Assisted living facilities, accessible units, and state-specific code supplements are all covered.

Complete CS210 Coverage

Lever kits, roses, escutcheons, chassis assemblies, strikes, and combination strikes all in one catalog page with part numbers and diagrams.

Same-Day Shipping

Most CS210 components ship same day from US warehouses. Call 845-935-0301 or use the contact page for pre-order compatibility support.

What Makes SecurityParts.com Different for CS210 Parts

We document the August 2015 crimp-to-snap rose transition with the exact four-part update kit (06-242, 08-029, A501-945, F206-496) for pre-2015 installations. No other parts supplier explains this before you place a wrong-part order.
We explain the assisted living NFPA 101 specification trap. Assisted living facilities do not qualify for the residential dwelling unit exception that allows separate deadbolts. This prevents non-compliant hardware installation on what is often one of the highest-scrutiny occupancy types for inspections.
We document the center-to-center field conversion as a no-parts field modification, eliminating unnecessary parts orders when a door prep dimension changes.
We carry CS210 interconnected lock parts alongside Schlage B Series deadbolt parts, Schlage ND Series cylindrical lock parts, and LCN door closer parts. One order covers the complete unit entry door hardware service call.
Same-day shipping from US warehouses on stocked parts. Free shipping on orders over $450.
30-plus years of commercial door hardware experience. We identify the generation, housing type, and escutcheon design from your description before the order ships.

Related Parts and Products at Security Parts

A complete multi-family unit entry door typically includes the interconnected lock, a surface door closer (required by fire code for self-closing on fire-rated corridor-to-unit assemblies), and sometimes an electric strike for access control on the corridor side. SecurityParts.com stocks all of these in one catalog.

For Schlage B Series deadbolt parts on unit entry doors where a separate deadbolt is permitted and specified instead of an interconnected lock, browse the deadbolts catalog. For Schlage ND Series and ALX Series cylindrical lock parts on common area corridor doors, mailroom doors, and amenity space doors in the same building, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on main building entry doors and management office doors requiring Grade 1 performance, browse the mortise locks catalog. For LCN door closer parts on unit entry doors and corridor fire doors in the same building, browse the door closers catalog. For Von Duprin exit device parts on building egress stairwells and exit doors, browse the commercial exit devices catalog.

Browse the complete all products and parts catalog to source Schlage, Von Duprin, LCN, Falcon, and Detex hardware in a single session.

Frequently Asked Questions About Schlage CS210 Interconnected Lock Parts

What is an interconnected lock and how is it different from a separate deadbolt and latchset?

An interconnected lock combines a cylindrical latch and a deadbolt with a mechanical connection that allows the inside lever to retract both simultaneously in one motion. A separate deadbolt and latchset require two inside operations to exit when the deadbolt is thrown. The interconnected lock's single-motion egress meets IBC and NFPA 101 requirements on most commercial occupancy doors. Where local code requires one-motion egress even on dwelling unit entry doors, an interconnected lock or mortise lock is the only compliant hardware solution.

What parts does the Schlage CS210 interconnected lock use?

The main CS210 replaceable parts are: lever kit (06-242, two levers), rose (08-029), inside escutcheon in Camelot or Plymouth design, outside housing assembly (B500 commercial spin ring or B60 residential spin ring), interconnect assembly, combination strikes (10-109 or 10-121), deadbolt strike (10-116), reinforcement ring (A501-945), and outside chassis assembly (F206-496 for crimp-to-snap conversions). All components are finish-specific.

What is the difference between crimp-on and snap-on roses on the Schlage CS210?

Schlage transitioned from crimp-on to snap-on roses in August 2015. Snap-on roses have retention dimples at the base. Crimp-on roses do not. For pre-2015 crimp-on installations requiring a lever or rose replacement, order all four parts together: lever kit 06-242, rose 08-029, reinforcement ring A501-945, and outside chassis assembly F206-496. For post-2015 snap-on installations, only the lever kit (06-242) and rose (08-029) are needed.

What center-to-center door preparations does the Schlage CS210 support?

The CS210 supports both 4-inch and 5-1/2-inch center-to-center door preparations through a field modification to the interconnect assembly. For 4-inch prep, remove two screws and the plate, then position the thumb-turn assembly with the thumb turn toward the bottom. For 5-1/2-inch prep, keep the plate in place with two screws. No additional parts are required for this conversion.

When is an interconnected lock required by code?

IBC and NFPA 101 require one-motion egress on most commercial doors. For Group R dwelling units (apartments, hotel rooms, dormitory rooms) with occupant loads of 10 or less, a separate deadbolt is generally allowed. However, some local jurisdictions require one-motion egress even on dwelling units. Assisted living facilities do not qualify for the residential dwelling unit exception under NFPA 101. Always verify local code before specifying hardware on multi-family and institutional projects.

What is the Schlage CS210 B500 vs B60 outside housing?

The B500 (commercial spin ring) includes a free-spinning cylinder collar that resists wrenching, a removeable security shield against ice-pick attacks, and a metal frame reinforcer with 3-inch screws. The B60 (residential spin ring) is the residential version without the additional attack resistance features. The B500 is the correct specification for commercial and institutional applications. Grip the cylinder collar and attempt to rotate it: free spin confirms B500; fixed confirms B60.

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Schlage B Series Deadbolt Parts: B500 and B600 Grade 1 Complete Guide Tuesday, June 23, 2026

Security Parts carries parts for the Schlage B Series commercial deadbolts. The B600 Series is Grade 1, Schlage's strongest commercial deadbolt. The B500 Series is Grade 2 for lighter applications. The most commonly replaced parts are the tailpiece (driver bar), the cylinder, and the strike plate. If a new B Series installation won't lock or unlock, rotate the driver bar 90 degrees toward the hinges before reinstalling. If the key turns but the bolt doesn't move, the tailpiece is stripped and needs replacement. Never use oil-based lubricants on B Series cylinders. Use graphite or silicone only.

Schlage B Series deadbolts are on more commercial and institutional doors than any other deadbolt brand in North America. They show up on office suites, storage rooms, corridor doors, exterior entries on healthcare and government buildings, and any secondary door on a commercial property that needs a reliable keyed bolt without the complexity of a full mortise lock.

When one fails, the repair is usually one of three things: a worn tailpiece, a failing cylinder, or a misaligned strike plate. Getting the right replacement part requires knowing the series (B500 vs B600), the cylinder format, and in some cases the finish code. This guide covers every component, every failure mode, every function, and the field-tested troubleshooting sequence that identifies the correct part before you order anything. Browse the complete Schlage B Series deadbolt parts catalog at SecurityParts.com for interactive diagrams on every model.

Grade 1 ANSI/BHMA rating on the Schlage B600 Series

1" Deadbolt throw on both B500 and B600 Series

UL 3hr Fire door listing with steel fire cup plate insert on B600

Everest 29 Default patented keyway on B600 Series for key duplication control

How a Commercial Deadbolt Works

A deadbolt operates differently from a spring latch. A spring latch clicks into the strike automatically when the door closes and retracts when the lever or knob is turned. A deadbolt does neither automatically. It extends only when the cylinder is turned with a key or the thumb turn is rotated, and it retracts only by the same means. Once extended, it cannot be pushed back by end pressure, a credit card, or a shimming tool.

Inside the lock body, the cylinder cam engages the tailpiece when the key is turned. The tailpiece connects the cam to the deadbolt bolt mechanism and drives the bolt in or out. On a single cylinder deadbolt, a thumb turn connects to the same bolt mechanism from the inside. On a double cylinder deadbolt, a key cylinder replaces the thumb turn on the inside.

The deadbolt throw on both B500 and B600 series is 1 inch. On a correctly installed B Series deadbolt, this 1-inch throw passes through the strike plate hole and engages at least 1 inch into the door frame. The metal dust box anchors the strike with 3-inch screws into the frame stud, which is why kick-in attacks that defeat the bolt still fail on a correctly installed B Series with the dust box in place.

B500 vs B600: Choosing the Right Series Before Ordering Parts

B500 Series

Grade 2 | Light Commercial and Multi-Family

7 functions. Optional fire rating with fire-rated deadbolt version. Optional indicator trim for status visibility. Adjustable backset (2-3/8 or 2-3/4 inch). Default deadbolt part 12-288 (square corner, 1 inch x 2-1/4 inch, 1 inch housing diameter). Standard door thickness 1-3/8 to 2-1/4 inch. Available in conventional, FSIC, and SFIC cylinder formats. Commercial 3-year limited warranty.

B600 Series

Grade 1 | Commercial and Institutional

Schlage's strongest commercial deadbolt. Hardened steel anti-saw pin in bolt. Hardened steel ball bearings stop drilling on through bolts. Free-spinning cylinder collar resists wrenching. Removeable security shield protects cylinder driver. Steel fire cup plate insert for UL 3-hour fire door listing. Default deadbolt part 12-296 (square corner, 1-1/8 x 2-1/4 inch). Default Everest 29 S123 keyway. Incorporates former B700 and B800 Primus-level series.

Important naming change: Locks previously sold as B700 Series (Primus cylinder) and B800 Series (Primus XP cylinder) are now incorporated as versions of the B600 Series with Primus or Primus XP cylinder specifications. If your building spec references B700 or B800, order B600 with the matching Primus cylinder specification. The physical lock and parts are the same. The naming changed; the hardware did not.

B600 Series Security Features: What They Mean for Parts Ordering

The B600 Series has a longer list of anti-attack features than the B500, and several of them directly affect parts compatibility and ordering.

Hardened Steel Anti-Saw Pin

A hardened steel pin is embedded in the deadbolt bolt body perpendicular to the bolt. If someone attempts to saw through the extended bolt, the saw blade hits the hardened pin and stops. The anti-saw pin is part of the bolt assembly and is not a separately replaceable component. If the bolt shows saw damage, the entire bolt assembly must be replaced, not just the pin.

Hardened Steel Ball Bearings on Through Bolts

The through bolts that mount the lock to the door have hardened steel ball bearings embedded in the bolt body. If someone attempts to drill through the bolt to remove the mounting screws, the drill bit contacts the ball bearing and spins without penetrating. These are built into the through bolt hardware and are not separately replaceable. If a through bolt is drilled, the entire bolt set requires replacement.

Free-Spinning Cylinder Collar

The cylinder collar on the B600 exterior is broadly angled and designed to spin freely when a wrench is applied to it. A fixed collar gives a wrench purchase to torque the cylinder out of the lock body. The free-spinning collar denies that purchase and the cylinder cannot be wrenched. The collar is part of the exterior cylinder housing assembly and is finish-specific. When ordering a replacement exterior cylinder assembly for a B600, confirm both the finish code and the security level (standard Everest 29, Primus, or Primus XP) before ordering.

Steel Fire Cup Plate Insert

The fire cup plate insert adds structural strength to the lock body and enables UL listing for 3-hour fire door use as an auxiliary lock. This component is factory-installed in B600 Series locks. It is not a separately field-replaceable component. If a B600 fire-rated installation requires a replacement lock body due to damage, specify the fire-rated version when ordering to ensure UL listing compliance on the fire-door assembly is maintained.

Every Replaceable Component in the Schlage B Series Deadbolt

Tailpiece (Driver Bar): The Most Misdiagnosed Failure

The tailpiece is the flat metal bar that connects the cylinder cam and the thumb turn to the deadbolt bolt mechanism. It is the most frequently misdiagnosed failure on a Schlage B Series deadbolt, and it is also the most common source of new-installation failures that are not actually component failures at all.

Tailpiece part numbers are length-specific and cylinder configuration-specific:

Part Number	Description	Length	Application
B202-557	Standard tailpiece, single cylinder	1.85 inch	Standard 1-3/4 inch door, single cylinder B Series
B202-558	Longer tailpiece, single cylinder	2.00 inch	Thicker doors where standard tailpiece doesn't reach
B220-032	Tailpiece, double cylinder	1.031 inch	B100, B250, B400, H, MD, and S200 series double cylinder

The tailpiece orientation fix that resolves 80% of new installation failures: When a new B Series installation will not lock or unlock, and the interior thumb turn won't move, the problem is almost never a defective lock. The official Schlage troubleshooting guide for this symptom is specific: remove the lock and rotate the driver bar fully toward the hinges, then reinstall with the deadbolt retracted and the key removed. This corrects the tailpiece orientation that was set wrong during installation. Technicians who do not know this spend unnecessary time diagnosing a non-existent hardware failure and sometimes order replacement parts for a lock that is not broken.

Deadbolt Bolt Assembly

The B500 default bolt is part 12-288 (square corner, 1 inch by 2-1/4 inch, 1 inch housing diameter, adjustable backset 2-3/8 or 2-3/4 inch). The B600 default bolt is part 12-296 (square corner, 1-1/8 inch by 2-1/4 inch, 1 inch housing diameter, adjustable backset 2-3/8 or 2-3/4 inch). Both series offer fixed backset options at 2-3/8, 2-3/4, 3-3/4, and 5 inches in addition to the adjustable standard.

Bolt assembly replacement is needed when the bolt has sustained physical damage from a forced entry attempt, when the anti-saw pin has been encountered by a saw blade, or when the bolt mechanism binds and will not extend or retract cleanly even after lubrication. The bolt faceplate (also called the drive-in faceplate) is a separately replaceable component that covers the bolt hole on the door edge and can be replaced without replacing the full bolt assembly when only the faceplate is damaged.

Cylinder Assembly

The cylinder is the keyed component in the exterior rose that drives the cam, which drives the tailpiece, which moves the bolt. The B Series supports multiple cylinder formats at ordering time:

Cylinder Format	Code	Description	Application
Conventional	Standard	Standard pinned cylinder, Everest 29 S123 keyway default	Most commercial installations
Primus	P	Second set of pins plus geographic exclusivity	Government, healthcare, high-security commercial
Primus XP	XP	UL 437 listed. Resists drilling and physical cylinder attack	High-security exterior doors, correctional facilities
FSIC	IC	Full-size interchangeable core. Core removeable by control key	Large campuses requiring frequent rekeying
SFIC	SFIC	Small format interchangeable core	Facilities with existing SFIC key systems

When replacing a B Series cylinder, confirm the security level installed before ordering. A standard Everest 29 cylinder looks physically identical to a Primus cylinder from the outside. The security level is on the original specification or on the key, which will have Primus branding on a Primus cylinder. Installing a standard cylinder to replace a Primus cylinder downgrades the security level of the opening without any visible indication that a change has been made.

Never use oil-based lubricants on a Schlage cylinder. Oil attracts dirt and debris that accumulates in the pin stack and causes premature cylinder failure. The cylinder becomes increasingly stiff until the key no longer turns. Use only graphite powder or silicone spray lubricant on B Series cylinders. If a cylinder has been lubricated with oil and is now stiff, cylinder replacement is the correct resolution. Flushing oil-contaminated cylinders does not restore full function reliably.

Strike Plate and Metal Dust Box

The B600 standard strike is 1-1/8 inch by 2-3/4 inch with square corners. The B500 standard strike is 1-1/8 inch by 2-3/4 inch. Both are available in ANSI curved lip, round cornered, and thimble configurations for different frame preparations.

The metal dust box (part B520-283) is installed behind the strike plate. It creates a reinforced pocket in the frame for the bolt to enter, and its 3-inch screws anchor into the door frame stud rather than just the door frame face. This is what gives the B Series its resistance to kick-in attacks. The bolt itself can withstand the force. What fails on most deadbolt kick-in attacks is the door frame around the strike, not the bolt or the lock body. The metal dust box with 3-inch screws prevents frame failure by distributing the force into the stud.

The dust box omission that facilities teams discover after a break-in: A very large percentage of deadbolt kick-in failures in commercial facilities happen on doors where the metal dust box was omitted at original installation because it was considered an optional component. It is not optional for any door where physical security matters. The B600 dust box using 3-inch screws is the difference between a door that fails a kick-in at approximately 100 foot-pounds and a door that holds at two to three times that force. If any B Series installation in your portfolio is missing the dust box, this is the most cost-effective security upgrade available per opening.

Thumb Turn Assembly

The thumb turn is the interior control on a single cylinder deadbolt that allows the bolt to be thrown or retracted from the inside without a key. The thumb turn assembly includes the turn itself, the rose, and the connecting components to the bolt mechanism. On a double cylinder deadbolt, the thumb turn is replaced by an interior key cylinder and the interior rose assembly changes accordingly.

Thumb turn replacement is needed when the turn becomes stiff or will not rotate fully, when physical damage to the thumb turn has occurred, or when the connection between the turn and the bolt mechanism has worn. The thumb turn assembly is finish-specific. Always confirm the finish code before ordering a replacement.

On a correctly installed lock, the thumb turn should operate with minimal resistance in either direction. A thumb turn that requires two-hand force to operate is not a characteristic of a fully functioning deadbolt. Check for strike plate misalignment before assuming the thumb turn mechanism has failed, as binding caused by a slightly misaligned strike is often mistaken for internal mechanism failure.

Exterior Rose and Cylinder Guard

The exterior rose is the cover plate visible on the door face around the cylinder. On the B600 Series, the exterior rose houses the free-spinning cylinder collar and acts as the primary tamper-resistant interface between the exterior and the door. The exterior rose is finish-specific. Scratch or impact damage to the rose requires a finish-matched replacement. The cylinder collar is part of the exterior assembly and is not separately replaceable from the rose on most B600 configurations.

B Series Deadbolt Functions: What Each One Does

The Schlage B Series deadbolt functions determine the operating configuration and the trim components required. Ordering a replacement cylinder, tailpiece, or trim without confirming the function code produces parts that may not be compatible with the specific installation.

Function	Series	Operation	Application
Single cylinder (B60N, B600 single)	B500, B600	Key exterior, thumb turn interior	Standard commercial and residential door
Double cylinder (B62N, B600 double)	B500, B600	Key both sides, no thumb turn	Doors with glass adjacent to lock where thumb turn would allow glass-break access
Privacy (B571, B600 privacy)	B600	Key exterior, interior indicator and coin turn, 180-degree window indicator	Restroom stalls, utility closets requiring occupied/vacant indication
Indicator (B571, B600 indication)	B600	180-degree status window, visible LOCKED/UNLOCKED from corridor	Healthcare patient rooms, offices where occupancy status must be visible from corridor
Key outside only (B600 key outside)	B600	Key exterior only, interior lever retracts bolt	Storerooms where interior free egress is required

The B600 Indication Trim: Why It Matters for Parts

The B600 indication trim function uses a patented 180-degree viewing window that wraps three sides of the exterior rose and displays a red or white background with LOCKED or UNLOCKED messaging. The large window is readable even from across a corridor. This is the "Know It's Locked" feature Schlage markets for healthcare and education applications where knowing a room's lock status without touching the hardware is a daily operational requirement.

The indication trim is not interchangeable with standard trim. It requires a specific exterior rose assembly with the viewing window housing. When ordering a replacement rose for a B600 indication trim installation, confirm the indication function variant before ordering. A standard rose does not retrofit into an indication trim installation because the housing geometry is different.

The B600 indication trim is available with red and white messaging backgrounds for readability by color-blind individuals, and in English, French, and Spanish language versions. Always confirm the language version when ordering a replacement trim assembly for an indication function installation.

Tailpiece Orientation: The Fix Nobody Documents Clearly

The official Schlage troubleshooting guide documents a specific procedure for a newly installed B Series deadbolt that will not lock or unlock. Most other resources on the internet describe this problem as a defective lock. It is not a defective lock in the overwhelming majority of cases.

The tailpiece has an orientation that must be set correctly relative to the door for the lock to function. If installed in the wrong orientation, the key turns, the thumb turn moves, but the bolt does not extend or retract. The fix takes under two minutes.

Remove the Lock from the Door

Unscrew the mounting screws holding the interior assembly to the exterior. Separate the two halves of the lock from the door bore. Do not disassemble the lock itself.

Rotate the Driver Bar Fully Toward the Hinges

With the lock removed, rotate the driver bar (tailpiece) fully in the direction of the door hinges. This resets the orientation to the correct starting position. Verify the deadbolt is fully retracted before reinstalling.

Reinstall with Key Removed and Bolt Retracted

Reinstall the lock with the deadbolt in the fully retracted position and with no key in the exterior cylinder. The key being in the cylinder during installation can shift the tailpiece orientation during the reinstallation process. Insert the key only after the lock is fully reinstalled and test operation.

Test Both Directions from Both Sides

Test with the exterior key in both locking and unlocking directions. Test with the interior thumb turn in both directions. If the lock now operates correctly, the issue was orientation only. No parts are needed. If the lock still does not operate after correct orientation, the tailpiece itself may be worn or stripped and requires replacement.

Key-Sticking and Cylinder Failure: When to Replace vs Lubricate

A stiff key on a B Series deadbolt is one of the most common service calls. The correct response depends on how long the stiffness has been present and what lubricant history the cylinder has.

New or recent installation, key stiff immediately: Check the cylinder alignment in the rose. A slightly off-center cylinder causes the key to bind against the cylinder housing on entry. Verify the exterior rose is seated flush before assuming cylinder failure.

Key stiff after months or years of use, never lubricated: Apply graphite powder to the key blade and work it in and out of the cylinder several times. For most B Series cylinders in commercial service, graphite applied every 12 months is sufficient maintenance. Do not use WD-40 or any oil-based product.

Key stiff after months or years of use, previously lubricated with oil-based product: The pin stack has collected oil-carried debris. Graphite will not flush this out. The cylinder requires replacement. Part numbers for B600 replacement cylinders must match the security level (standard Everest 29, Primus, or Primus XP) of the original installation.

Key turns freely but bolt does not move: The tailpiece connection has failed. The key is operating the cam but the cam is no longer driving the tailpiece into the bolt mechanism. Remove the lock, inspect the tailpiece for wear or stripping, and replace with the correct length tailpiece (B202-557 for standard doors or B202-558 for thicker doors).

Key can only be removed in one position (locked or unlocked) but not the other on a new installation: Rotate the driver bar fully toward the hinges and reinstall. This is a tailpiece orientation issue identical to the general non-operating procedure above.

Strike Plate Alignment: The Most Common Source of Binding

A deadbolt that operates smoothly with the door open but feels stiff or fails to fully extend when the door is closed is almost always a strike plate alignment problem. The bolt pocket in the strike must be centered on the bolt throw for the bolt to enter cleanly and without side friction.

Door settling is the most common cause of gradual strike plate misalignment in commercial buildings. Wood frame doors settle as the building ages and the door shifts slightly in its frame. Hollow metal frame doors can shift if the frame anchoring fasteners loosen over time. Either way, the result is a bolt that contacts the edge of the strike pocket rather than entering it cleanly.

Correcting strike plate misalignment does not always require a new strike. If the misalignment is small (2mm or less), enlarging the bolt pocket with a chisel is the fastest correction. If the misalignment is larger, the strike must be relocated or a new strike installed with a bolt pocket at the corrected position.

A strike that has been in service for 10 or more years on a high-traffic exterior door may also show deformation of the bolt pocket lip where repeated bold throw impact has worn or bent the steel. A deformed strike produces a deadbolt that feels rough on every locking cycle. Replace the strike when deformation is visible.

How to Identify Your B Series Model Before Ordering Parts

Three pieces of information are required before any B Series parts order.

1. Series designation (B500 or B600): The series is stamped or labeled on the lock body, visible when the interior assembly is removed. If the label is missing or worn, the grade level can sometimes be identified by the security features: if the exterior cylinder collar spins freely when gripped and twisted, it is a B600. If it is fixed, it may be a B500 or an older B series.

2. Cylinder security level: Standard Everest 29, Primus, or Primus XP. The key itself will have Primus branding if a Primus cylinder is installed. UL 437 markings on the cylinder face confirm Primus XP. Ordering a standard cylinder to replace a Primus cylinder downgrades security without any visible indication to building management.

3. Finish code: The finish is on the original specification or visible on the hardware. Common B Series finishes include 605 (bright brass), 619 (satin nickel), 622 (matte black), 625 (bright chrome), 626 (satin chrome), and 643e (aged bronze). Trim components are finish-specific. A replacement thumb turn or rose in the wrong finish requires a return and reorder.

Browse the Schlage B Series deadbolt parts catalog at SecurityParts.com for interactive diagrams by model. For the complete Schlage commercial hardware range including ND Series cylindrical locks, L Series mortise locks, and B Series deadbolts, browse the Schlage commercial hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for Schlage B Series Deadbolt Parts

Tailpiece guidance, cylinder security level documentation, dust box importance, and same-day shipping on stocked parts.

Tailpiece Orientation Guidance

We document the driver bar rotation fix that resolves most new installation failures without any parts replacement. Knowing this before calling in a service order saves time and unnecessary returns.

Cylinder Security Level

We document that standard and Primus cylinders look identical from outside. Replacing a Primus with standard downgrades security silently. We confirm the security level before the order ships.

Dust Box Documentation

We explain why the metal dust box with 3-inch screws is the most cost-effective security upgrade per opening. Most facilities don't know it was omitted until after a kick-in incident.

Same-Day Shipping

Most B Series parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for pre-order compatibility support.

What Makes SecurityParts.com Different for Schlage Deadbolt Parts

We document the tailpiece orientation procedure that resolves most new installation failures without ordering any parts. No other parts supplier explains this in buyer-facing content, which means unnecessary part orders happen constantly.
We explain that B700 and B800 Series locks are now incorporated into B600 Series with Primus cylinder specifications. Facilities maintaining these older specifications can order confidently without confusion about what has changed.
We document the metal dust box importance as the most cost-effective physical security upgrade per deadbolt opening. The 3-inch screws that anchor into the stud are the difference between a door that fails a kick-in and one that holds.
We document the oil lubricant contamination failure mode. Cylinders lubricated with WD-40 or similar products need replacement, not additional lubrication. This prevents repeated unnecessary service calls on the same cylinder.
We carry Schlage B Series parts alongside Schlage ND and ALX Series cylindrical lock parts, Schlage L Series mortise lock parts, and LCN door closer parts. One order services the complete building opening.
Same-day shipping from US warehouses on stocked parts. Free shipping on orders over $450.

Related Parts and Products at SecurityParts.com

Schlage B Series deadbolts are typically installed alongside cylindrical locksets on the same door or in the same building. A complete commercial service call for a building's lock hardware often covers all of these at once.

For Schlage ND Series, ALX Series, and Falcon T Series cylindrical lock parts on interior corridor and office doors in the same facility, browse the cylindrical locks catalog. For Schlage L Series and Falcon MA Series mortise lock parts on high-security entry doors in the same building, browse the mortise locks catalog. For Von Duprin electric strike parts on access-controlled entries in the same facility, browse the electric strikes catalog. For Von Duprin and Falcon exit device parts on egress doors in the same building, browse the commercial exit devices catalog. For LCN door closer parts on any door with automatic closing hardware, browse the door closers catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware in a single session.

Frequently Asked Questions About Schlage B Series Deadbolt Parts

What is the difference between the Schlage B500 and B600 Series deadbolts?

The B500 is Grade 2 for lighter commercial and multi-family applications with 7 functions and an optional fire rating. The B600 is Grade 1 with hardened steel anti-saw pins, ball bearings to stop drilling on through bolts, a free-spinning cylinder collar to resist wrenching, a security shield against cylinder manipulation, and a steel fire cup plate insert for UL 3-hour fire door listing. The former B700 and B800 Series names are now incorporated into B600 with Primus cylinder specifications.

What is the tailpiece on a Schlage B Series deadbolt and how do I replace it?

The tailpiece (driver bar) connects the cylinder cam and thumb turn to the deadbolt bolt mechanism. Standard single cylinder tailpiece is part B202-557 (1.85 inch). Longer single cylinder tailpiece is B202-558 (2 inch). Double cylinder tailpiece is B220-032 (1.031 inch). If a new installation won't lock, rotate the driver bar fully toward the hinges before reinstalling. If the key turns but the bolt doesn't move after correct orientation, the tailpiece is stripped and requires replacement.

What keyway does the Schlage B600 Series use by default?

The B600 Series uses the Everest 29 S123 patented keyway as standard. This prevents unauthorized key duplication. The B600 is upgradable to Primus for geographic exclusivity and a second pin set, and to Primus XP for UL 437 high-security listing. The B700 and B800 Series names previously identified Primus levels and are now B600 variants.

What causes a Schlage deadbolt to not lock or unlock after installation?

The most common cause on new installations is incorrect tailpiece orientation. Remove the lock, rotate the driver bar fully toward the hinges, and reinstall with the bolt retracted and key removed. If the bolt operates with door open but binds when closed, the strike plate is misaligned. If the key turns but the bolt doesn't move, the tailpiece has failed and needs replacement. A key that sticks after extended use requires cylinder replacement.

What strike plate does the Schlage B600 Series use?

The B600 standard strike is 1-1/8 inch by 2-3/4 inch with square corners. The metal dust box (part B520-283) installs behind the strike using 3-inch screws that anchor into the door frame stud. This is the critical component that prevents kick-in failures. Many B Series installations are missing the dust box, making this the most cost-effective physical security upgrade available per opening.

What is the Schlage B Series single cylinder vs double cylinder deadbolt?

Single cylinder (B60N, B600 single) uses a key exterior and thumb turn interior. Double cylinder (B62N, B600 double) requires a key on both sides. Double cylinder is specified on doors with glass near the deadbolt where someone could break the glass and reach a thumb turn. Many building codes prohibit double cylinder deadbolts on required egress doors because they delay exit during emergencies. Always verify local code before specifying double cylinder on any egress path.

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Schlage L Series and Falcon MA Series Mortise Lock Parts: Complete Field Guide Monday, June 22, 2026

Mortise locks are the most complex mechanical lock type to source replacement parts for because the function code determines which components are correct, and parts across different function codes are not interchangeable even when the cases look identical. SecurityParts.com carries parts for the Schlage L Series Grade 1 (40-plus functions, 33 lever styles) and Falcon MA Series Grade 1 (high-traffic institutional, SFIC-compatible). The function code, door handing, and manufacture date are all required before ordering any chassis, armor front, latchbolt, spindle, or cylinder cam. The L9050 universal case is the single most important inventory item because it can be transformed into nine different L Series functions with the right additional parts.

Mortise locks outlast cylindrical locks by a factor of 3 to 5 in commercial service. They are on the entry doors, the main corridors, the healthcare and government facilities where reliability is not optional. When one needs service, the parts tree is deeper and more function-specific than anything in the cylindrical lock world.

The Schlage L Series alone covers more than 40 functional options, 33 lever designs, and 14 finishes. Its parts split into chassis components, cylinder components, trim components, and function-specific parts that are not interchangeable even within the same L Series family. A lever return spring for an L9010 passage function is not the same servicing need as a spindle assembly for an L9080 storeroom function. Getting any one of these wrong means a return, a reorder, and a door that stays out of service for another week. Browse the complete mortise lock parts catalog at SecurityParts.com for interactive diagrams on every function and model.

40+ Mechanical functions in the Schlage L Series

33 Lever designs in solid brass or stainless steel in the Schlage L Series

3-5x Longer service life of mortise vs cylindrical locks in commercial settings

UL 3hr Fire door rating on both Schlage L Series and Falcon MA Series

How a Mortise Lock Differs from a Cylindrical Lock

A mortise lock installs into a pocket (the mortise) cut into the edge of the door, typically 4 inches deep, 6 inches tall, and 1 inch wide. The entire lock mechanism lives inside this pocket with only the armor front plate visible on the door edge and the levers and roses visible on the door face. This concealed mounting is what gives mortise locks their tamper resistance advantage over cylindrical bore locks where the mechanism is partially exposed.

Inside the mortise case, the mechanism includes a spring latchbolt for automatic latching, an auxiliary deadlatch plunger that deadlocks the latchbolt when the door closes against the strike, a separate deadbolt on many functions, a spindle connecting the inside and outside levers through the case, and a mortise cylinder that controls the deadbolt cam. All of these operate in a single cast body. This is what makes mortise locks the strongest lock type for high-security commercial doors but also the most complex to source replacement parts for correctly.

The auxiliary deadlatch detail that costs locksmiths service calls: The auxiliary deadlatch plunger beside the latchbolt must be fully depressed by the strike plate when the door closes for the deadlocking function to engage. If the strike is positioned so the plunger does not contact the strike face, the latchbolt is not deadlocked and can be retracted by a credit card, a loiding tool, or end pressure. Strike misalignment greater than approximately 1.5mm vertical is enough to defeat deadlocking on any mortise lock. When a customer reports a door that feels secure but opens with shim pressure, the strike alignment is almost always the cause, not a failed latchbolt.

Schlage L Series: The Commercial Benchmark Mortise Lock

The Schlage L Series has been the benchmark commercial mortise lock specification in North America for decades. Government buildings, healthcare facilities, higher education campuses, institutional projects. If a building was built to a commercial standard after 1970, there is a very high probability it has L Series locks on the entry and secured doors.

The L Series offers beyond-Grade-1 strength in a mortise chassis. The anti-saw pin in the deadbolt prevents cut-through attacks. The security blocking hub prevents lock access by removing the levers. Lock monitoring options including request to exit (RX), latchbolt monitoring (LX), door position sensor (DPS), and deadbolt monitoring (DM) are available depending on the function. The patented Everest 29 S123 keyway prevents unauthorized key duplication as standard. Primus restricted cylinders with geographic exclusivity and advanced key control are available for facilities requiring maximum key system security.

Reading the Schlage L Series Model Number

The model number decodes every specification needed to source the correct replacement parts. The format is L or LV plus function group plus deadbolt indicator plus cylinder suffix.

Code Element	Meaning	Example
L	Standard Schlage L Series chassis	L9080
LV	Vandlgard chassis for abuse/vandalism resistance	LV9080
Function group	The lock operating function (e.g. 9080 = storeroom)	L9080
Deadbolt indicator	0 = no deadbolt. 4 = with deadbolt (L9460 adds deadbolt to basic functions)	L9460
P	6-pin full-face mortise cylinder with Schlage logo included	L9080P
L	Less cylinder (customer supplies cylinder)	L9080L
C	Concealed mortise cylinder included	L9080C
R	Full-size interchangeable core cylinder	L9080R

The Most Common Schlage L Series Functions

Function	ANSI	How It Works	Application
L9010	Passage	Latchbolt retracted by lever from either side. No locking.	Corridors, vestibule passages, non-secured internal doors
L9020	Privacy	Inside push button locks outside lever. Emergency coin release from outside.	Restrooms, private offices
L9040	Classroom	Outside lever locked by key from outside. Inside always free. No deadbolt.	Classrooms, conference rooms requiring exterior key lockdown
L9050	Entrance/Office	Push button locks outside lever. Key or inside lever unlocks. Latch and deadbolt.	Executive offices, secured administrative areas
L9060	Vestibule	Key in outside lever locks/unlocks it. Inside lever always free.	Building lobby control, vestibule entries
L9070	Classroom Security	Outside lever locked by key from outside only. Inside always free. With latch and deadbolt.	K-12 classrooms with full deadbolt lockdown requirement
L9080	Storeroom	Outside lever always inoperative, entry by key only. Inside always free.	Storage, server rooms, supply areas, secure labs
L9082	Storeroom/Closet	Same as L9080 but latchbolt retracted by key from either side. Both levers always inoperative.	Secure closets, equipment rooms requiring full key control

The escutcheon vs rose trim mistake: When a function change is needed on an L Series installation that currently has escutcheon trim, the entire escutcheon set (inside and outside) must be replaced when converting to a different function. If the door uses rose (sectional) trim, no additional trim parts are required for most function conversions. Ordering just the chassis for a function conversion on an escutcheon-trim installation and not ordering the matching escutcheon set for the new function leaves the job incomplete and the door with mismatched trim.

The L9050 Universal Case: The Most Important Inventory Item

Schlage designed the L9050 universal case to be transformed into nine different L Series functions by adding specific conversion components. This is the single most important piece of knowledge for facilities managers who maintain large L Series inventories.

A facility stocking the L9050 universal case can reconfigure it for passage, entrance/office, classroom, storeroom, and other functions using the Schlage Universal Transformation Guide (document 109436). The guide specifies exactly which additional parts are required for each function conversion. This approach eliminates the need to stock nine separate configured cases and eliminates the lead time required to order an uncommon factory-configured function combination.

The transformation requires only a few additional parts per function change, typically a chassis conversion kit and potentially trim components. The labor time is minimal for a locksmith familiar with the L Series. For facilities with 50-plus L Series locks across multiple functions, this single knowledge point eliminates thousands of dollars in stocked inventory and weeks of lead time across the building's service life.

Every Replaceable Component in the Schlage L Series

Lock Case (Chassis)

The Schlage L Series chassis (also called the lock case or case body) is the cast iron or steel housing that lives inside the mortise pocket. The chassis contains the latchbolt mechanism, the auxiliary deadlatch plunger, the deadbolt (on applicable functions), the spindle hubs, the cylinder cam track, and the internal function mechanism. The base chassis for L9050 is part L283-133. The LV-series Vandlgard chassis substitutes the standard function mechanism with the Vandlgard clutch assembly that prevents forced lever torque from engaging the deadbolt or latch.

Chassis replacement is required when the internal mechanism fails, when a function change is needed on an ND-style installation, or when the case sustains physical damage from a break-in attempt. Chassis replacement requires door disassembly, which typically means removing the levers, roses or escutcheons, through-bolts, and the case itself from the mortise pocket. Always verify the backset (2-3/4 inch standard on L Series) and door thickness accommodation before ordering a replacement case.

Latchbolt Assembly

The latchbolt is the beveled spring bolt that extends from the lock case and clicks into the strike plate when the door closes. On the Schlage L Series, the standard latchbolt is a two-piece deadlocking latchbolt with a separate auxiliary plunger alongside the main bolt. The auxiliary plunger, when depressed by the strike plate face on door closing, deadlocks the latchbolt against being retracted from the latch edge by a shimming tool or card.

The two-piece construction means the main bolt and the auxiliary plunger are separate components within the latchbolt assembly. If the auxiliary plunger fails to depress or return correctly, the deadlocking function is compromised even though the latch itself still operates normally. This is a silent failure: the door latches and appears secure but the deadlocking protection is absent. Inspect the auxiliary plunger on any L Series installation where security has been questioned, even if the latch seems to operate normally.

Armor Front (Armored Front / Scalp Plate)

The armor front is the hardened steel face plate visible on the door edge that covers the mortise case opening. It presents the latchbolt and deadbolt holes aligned with the case components below, and it resists pry, drill, and chisel attacks on the lock body. The Schlage L Series armor front is 1-1/4 inch by 8 inch and adjustable for door bevel.

Armor fronts are finish-specific and function-specific. The Schlage part 09-663 in 626 (satin chrome) finish covers the L9050, L9056, L9060, L9070, L9071, L9080, and L9082 functions. Part 09-666 covers a different configuration. Ordering an armor front without confirming the finish code and function produces a part that either does not fit or does not match the door hardware. Always pull both pieces of information from the installed hardware before ordering.

Spindle and Hub Assembly

The spindle is the square connecting rod that passes through the case and links the inside and outside levers. The hub is the internal component that connects the spindle to the case mechanism and holds the lever return springs. The lever return springs in the hub are sized to provide approximately 2 pounds of return force at the lever tip. When these springs fatigue, the lever droops below horizontal even with no other visible damage to the lock.

The Schlage L Series uses a security blocking hub that prevents gaining access to the lock mechanism by removing the levers. On locks where this is not a concern, a standard hub is fitted. Vandlgard versions use a hub with a clutch mechanism that allows the outside lever to rotate freely without engaging the mechanism when excessive torque is applied, preventing the forced-lever attack that can defeat a standard L Series lock in some configurations.

Mortise Cylinder and Cylinder Cam

The mortise cylinder screws into the case face and drives the deadbolt cam. The cylinder body is threaded at approximately 1.156 inch diameter with 32 threads per inch. Standard L Series cylinders include the Everest 29 S123 patented keyway in 6-pin conventional format. The cam is the component on the back of the cylinder that engages the deadbolt throw mechanism inside the case.

Cylinder cam replacement is one of the most frequently misunderstood service tasks on mortise locks. The cam must match both the cylinder type and the function. The Schlage L583-254 cam is used on standard conventional Schlage L Series mortise cylinders. The L583-446 cam is for Schlage modular mortise cylinders. The K510-730 cam is the standard cam for IC housings and works across Schlage IC configurations, Falcon non-deadbolt functions, and several other manufacturer applications. Using the wrong cam on a mortise cylinder produces a lock that either cannot throw the deadbolt or throws it only in one rotation direction.

Thumbturn Assembly

The thumbturn (T-turn) is the interior control that throws the deadbolt on applicable L Series functions. The Schlage part 09-509 T-turn fits doors from 1-3/8 inch to 1-7/8 inch thick with a rose diameter of approximately 1-3/4 inch. Thumbturn replacement is required when the thumbturn becomes stiff, when the internal cam connection wears and the turn no longer throws the deadbolt cleanly, or when the turn is damaged by abuse or attempted tampering. Always confirm door thickness before ordering a thumbturn replacement to ensure the correct depth is specified.

Lever Return Spring

The lever return spring (Schlage part L283-040 for the L Series) provides the return force that brings the lever back to horizontal after it is depressed. This is the highest-wear component in the L Series hub assembly and fails through fatigue on high-traffic doors. Lever sag is the primary symptom. The lever return spring is available individually and is far less expensive than replacing the full hub assembly. Replace the spring first before assuming the hub or spindle requires replacement.

Strike Plate

The L Series strike is the steel plate mortised into the door frame that receives the latchbolt and deadbolt. The standard L Series strike is a full-length plate matching the 8-inch armor front. Strike replacement is needed when the bolt pockets deform from extended high-traffic use, when the door has settled and the bolt pockets no longer align with the bolts, or when the frame is repaired and the original strike prep is modified. Always confirm whether the strike is a standard or a high-security box strike before ordering.

Falcon MA Series: The High-Traffic Value Mortise Lock

The Falcon MA Series is the Grade 1 mortise lock positioned below the Schlage L Series in price but at the same ANSI/BHMA Grade 1 certification level for both operational and security performance. It meets ANSI A156.13 Series 1000 Operational Grade 1 and Security Grade 1 with all standard trims and conventional mortise cylinders. It is UL listed for 3-hour fire doors under both UL 10B neutral pressure and UL 10C positive pressure testing, the same fire listing as the L Series.

Falcon MA Series Key Specifications

Specification	Detail
ANSI rating	A156.13, Series 1000, Grade 1 Operational and Security
Fire rating	UL 10B, UL 10C, UBC 7-2 (3-hour fire door)
Latchbolt	Two-piece stainless steel, mechanical anti-friction bolt, 3/4 inch projection, field reversible
Spindle	Independent, breakaway design at maximum 480 in-lb to protect chassis
Armor front	1-1/4 inch by 8 inch, brass or stainless steel, adjustable for door bevel, reinforced with heavy gauge steel stabilizing ribs
Backset	2-3/4 inch standard
Door thickness	1-3/4 inch to 1-7/8 inch standard
Cylinder format	6-pin solid brass conventional, 5-pin keyed standard. SFIC available in 6 or 7-pin.
Cylinder keyway	Falcon G keyway on conventional cylinders. A keyway on IC cores.

Falcon MA Series Spindle Breakaway

The Falcon MA Series uses independently mounted spindles designed to break away at a maximum of 480 inch-pounds of torque. This is the Falcon equivalent of the Schlage Vandlgard function: when someone applies excessive forced torque to the outside lever in an attempt to retract the latch or deadbolt, the spindle detaches from the chassis before that force reaches the internal mechanism. The chassis remains intact and functional. The spindle requires replacement after a breakaway event, but the chassis and all other components are preserved.

This matters for parts ordering. After a forced entry attempt on a Falcon MA Series installation where the door resisted entry, the spindle is likely broken or detached even if the door looks fine from the outside. Always check the spindle engagement when servicing an MA Series lock that has experienced a forced entry attempt. A loose or rattling lever with a firm chassis is the diagnostic sign of a broken spindle.

Falcon MA Series Cylinder Compatibility

The Falcon MA Series accepts cylinders from multiple sources. Conventional cylinders ship with the Falcon G keyway standard. SFIC (Small Format Interchangeable Core) cylinders are available in 6-pin or 7-pin configurations and accept Falcon SFIC cores as well as compatible cores from other manufacturers. Schlage Classic cylinders in C, E, and CE keyways operate the Falcon MA Series using the 5622-STD cam, which is a notable cross-brand compatibility feature that simplifies cylinder sourcing on projects where a Schlage key system is already in use.

The cylinder guard (parts A08790 and A08794) accommodates different cylinder lengths and door thicknesses. The correct cam must be specified based on the cylinder type and function. The factory supplies the correct cam when the function and door thickness are specified at order time. On field replacements, always confirm which cam is installed before ordering a replacement cylinder, as mismatching the cam to the cylinder produces a lock that operates in only one direction.

Falcon MA Series Functions

The Falcon MA Series uses a different function coding system from the Schlage L Series but covers similar ANSI function categories. Common functions include MA101 (passage), MA301 (privacy), MA381 (entrance), MA461 (classroom), and MA481 (storeroom). All function codes in the MA Series follow the pattern MA + function number + keyway/cylinder designation. When ordering replacement parts for the MA Series, confirm the MA function code from the label on the case body before selecting any chassis, latchbolt, or trim component.

Mortise Lock vs Cylindrical Lock: When Does Mortise Make Sense?

Mortise locks cost significantly more than cylindrical locks to purchase and install. They require a deeper and more complex door preparation. Parts are more function-specific and more expensive per component. Despite all of this, mortise locks are the correct specification in specific contexts where their advantages justify the cost.

Factor	Mortise Lock	Cylindrical Lock
Deadbolt integration	Deadbolt integrated into case on applicable functions	Separate deadbolt required for deadbolt security
Anti-shim protection	Auxiliary deadlatch plunger standard on most functions	Deadlatch feature present on commercial Grade 1 models
Attack resistance	Concealed mechanism, harder to attack from exterior	Mechanism partially exposed at bore through door
Service life	3 to 5x longer than cylindrical in commercial use	Standard commercial service life
Function flexibility	40-plus functions on L Series, electrified options extensive	24 functions on ND Series Grade 1
Installation complexity	Higher. Requires mortise pocket, precise alignment	Lower. Standard cylindrical bore prep
Parts cost	Higher. Function-specific, finish-specific components	Lower. More universal components across functions

Mortise locks are correctly specified on main building entries, secured office suites, healthcare patient area doors where tamper resistance is required, government facility doors, and any opening that justifies the higher purchase cost through extended service life. For interior corridor doors, storage rooms on lower-security floors, and any door where Grade 2 performance is sufficient, browse the cylindrical lock parts catalog for Schlage ALX Series or Falcon T Series alternatives that serve the application at lower cost.

How to Identify Your Mortise Lock Before Ordering Parts

The correct identification process for mortise lock parts ordering requires three pieces of information, all of which come from the installed hardware.

Find the Model Number on the Case

Remove the inside lever and rose or escutcheon to expose the lock face. The model number (L9080, LV9070, MA481) is stamped or labeled on the case face or on the armor front. On Schlage L Series, the LV prefix confirms a Vandlgard chassis. On Falcon MA Series, the MA prefix and function number identify the model. Do not order parts based on the door hardware appearance alone. A standard L9080 and an LV9080 Vandlgard look identical from the outside but use different internal components.

Confirm the Cylinder Type

The cylinder type (conventional, FSIC, SFIC, less cylinder) determines which cam is installed and which replacement cylinders are compatible. Conventional cylinders have a solid body with a visible keyway. IC cylinders have a removable core with a control key function. The P, R, L, or C suffix in the model number confirms the original cylinder specification. If the label is worn, remove the cylinder and measure the body diameter and check whether a core is present.

Note the Finish Code and Door Handing

Armor fronts, levers, roses, and escutcheons are finish-specific. The finish code is typically a three-digit number (626 = satin chrome, 619 = satin nickel, 613 = oil rubbed bronze). On Falcon MA Series, the door handing must also be specified for most keyed functions because the chassis is handed. Schlage L Series locks are non-handed for most standard functions, but some specialized function configurations require hand specification.

SecurityParts.com organizes both series in the mortise lock parts catalog by brand and series with interactive exploded diagrams on every model. For the complete Schlage hardware catalog including L Series, ND Series, and B Series deadbolts, browse the Schlage commercial hardware parts catalog. For Falcon hardware including MA Series mortise locks and T Series cylindrical locks, browse the Falcon commercial hardware parts catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose Security Parts for Mortise Lock Parts

Function-specific diagrams, cylinder cam guidance, L9050 universal case knowledge, and same-day shipping on stocked components.

Function Code Guidance

Armor front, chassis, latchbolt, and cam are all function-specific. We document which part applies to which function so you do not receive a physically fitting part that does not operate correctly.

L9050 Universal Case

We document the universal transformation capability of the L9050 case. Facilities that know this stock one case type instead of nine and reduce inventory costs significantly.

Cross-Brand Cylinder Support

Falcon MA Series accepts Schlage Classic cylinders with the 5622-STD cam. We document this compatibility so you do not need to maintain separate cylinder inventories for mixed-brand buildings.

Same-Day Shipping

Most L Series and MA Series parts ship same day from US warehouses. A failed mortise lock on a secured entry is not a problem that waits a week for parts. Call 845-935-0301 for pre-order confirmation.

What Makes SecurityParts.com Different for Mortise Lock Parts

We document the auxiliary deadlatch plunger alignment requirement. Strike misalignment greater than 1.5mm vertical defeats deadlocking without any visible symptom. This field fact prevents misdiagnosed latchbolt replacements that do not fix the actual problem.
We document the L9050 universal case transformation capability. Facilities managers who know this use one case type for nine functions instead of stocking nine separate cases. No other parts supplier explains this in their buyer-facing content.
We document the Falcon MA Series spindle breakaway mechanism. A loose lever after a forced entry attempt means spindle replacement, not chassis replacement. Ordering the less expensive spindle instead of a full chassis saves significant cost on post-incident repairs.
We document the Schlage Classic cylinder cross-compatibility on Falcon MA Series using the 5622-STD cam. Buildings with mixed L Series and MA Series locks can use one cylinder inventory rather than two.
We carry Schlage and Falcon mortise lock parts alongside cylindrical lock parts, deadbolt parts, and door closer parts. One order services the complete commercial door opening.
Same-day shipping from US warehouses on stocked parts. Free shipping on orders over $450.

Related Parts and Products at SecurityParts.com

Mortise locks are part of a complete commercial door opening. The main entry door that has an L Series mortise lock also has a door closer, often an electric strike or exit device, and sometimes alarm hardware on the same opening or building.

For Schlage B Series deadbolt parts on doors that use a separate deadbolt alongside a mortise lock on a secondary opening, browse the deadbolts catalog. For Schlage ND Series, ALX Series, and Falcon T Series cylindrical lock parts on interior doors in the same facility, browse the cylindrical locks catalog. For Von Duprin electric strike parts on access-controlled entries in the same building, browse the electric strikes catalog. For Von Duprin and Falcon exit device parts on egress doors in the same facility, browse the commercial exit devices catalog. For LCN door closer parts on any door in the facility with automatic closing hardware, browse the door closers catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware in a single session.

Frequently Asked Questions About Mortise Lock Parts

What mortise lock series does SecurityParts.com carry parts for?

SecurityParts.com carries replacement parts and interactive diagrams for the Schlage L Series Grade 1 mortise lock and the Falcon MA Series Grade 1 mortise lock. Both series have dedicated model pages organized by function code with exploded diagrams for visual part confirmation before ordering.

What is the Schlage L Series function code and why does it matter for parts ordering?

The function code identifies how the lock operates: which side is always free, which side is keyed, whether a deadbolt is present. Common codes include L9010 (passage), L9050 (entrance/office), L9070 (classroom with full deadbolt), and L9080 (storeroom, outside lever always locked). The function code determines which chassis, latchbolt, armor front, and cylinder cam are correct. Parts across different function codes are not interchangeable even when the cases appear identical.

What is the L9050 universal case and why is it important?

The Schlage L9050 universal case can be transformed into nine different L Series functions using specific conversion parts per the Schlage Universal Transformation Guide. A facility stocking the L9050 can reconfigure it for multiple functions without ordering nine separate configured cases. This eliminates significant inventory carrying cost and lead time for uncommon function combinations. It is the most important single inventory knowledge point for facilities maintaining large L Series installations.

What is the difference between the armor front and the latch front on a mortise lock?

The armor front (armored front/scalp plate) is the hardened steel face plate on the door edge covering the mortise case and resisting pry and drill attacks. It is finish-specific and function-specific. The latch front is the internal component housing the latchbolt mechanism inside the case. Both are separate replaceable parts. The Schlage L Series armor front part 09-663 fits L9050, L9056, L9060, L9070, L9071, L9080, and L9082 functions in the 626 satin chrome finish.

Can the Falcon MA Series accept interchangeable core cylinders?

Yes. The Falcon MA Series accepts SFIC cylinders compatible with Falcon and some other manufacturers' cores. The core removes by rotating the control key and pulling gently, enabling immediate rekeying without disassembling the lock. SFIC cylinders are available in 6-pin or 7-pin configurations. Schlage Classic cylinders in C, E, and CE keyways also operate the MA Series using the 5622-STD cam.

What causes drooping levers on a mortise lock and how do I fix it?

Drooping levers are most commonly caused by fatigued lever return springs in the hub assembly. The springs provide approximately 2 pounds of return force at the lever tip and fatigue over extended service. Replace the lever return spring (Schlage L283-040) before assuming the hub or spindle requires replacement. On Falcon MA Series, also check whether the spindle breakaway has engaged after a forced entry attempt, as a detached spindle produces a loose lever that requires spindle replacement, not spring replacement.

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Schlage ND Series, ALX Series and Falcon T Series Cylindrical Lock Parts Guide Friday, June 19, 2026

SecurityParts.com carries parts for three commercial cylindrical lock series: the Schlage ND Series Grade 1 (24 mechanical functions, beyond-Grade-1 strength), the Schlage ALX Series Grade 2 (single modular chassis, field function change), and the Falcon T Series Grade 1 (extra heavy-duty, accepts any manufacturer's cylinder). The function code determines the correct chassis, spring cage, and trim components. Never order parts by appearance alone. The ND Series and ALX Series share lever styles for visual suiting but use different chassis and function kits. Parts that fail first are the spring cage, latch, and cylinder. Always confirm function code and manufacture date before ordering.

Commercial cylindrical locks are on more doors per building than any other lock category. Office corridors, storage rooms, restrooms, classrooms, patient rooms, server closets. Every one of those doors has a chassis, a latch, a spring cage, a cylinder, levers, and a strike. When one component wears or fails, replacing it correctly the first time depends entirely on having the right series and function code before you open any catalog page.

SecurityParts.com stocks parts for the three most widely installed commercial cylindrical lock series: the Schlage ND Series, the Schlage ALX Series, and the Falcon T Series. This guide covers every component, the function codes that determine which parts you need, what fails first, and how to order without a return. Browse the complete cylindrical lock parts catalog at SecurityParts.com for interactive diagrams on every model.

24 Mechanical functions available in the Schlage ND Series

3,100 in-lb Abusive lever torque resistance on the Schlage ND Series

Grade 1 ANSI/BHMA rating on both the ND Series and Falcon T Series

1,600 lbs Offset lever pull resistance on the Schlage ND Series

The Three Series at Security Parts: How They Compare

Schlage ND Series

Grade 1 | Beyond-Grade-1 Strength

The strongest-selling commercial cylindrical lock in North America. 24 mechanical functions. Withstands 3,100 in-lb of abusive lever torque, 2.5x the Grade 1 standard. 1,600 lb offset lever pull resistance. Supports conventional, FSIC, and SFIC cylinder formats. Available with Vandlgard anti-ligature protection on all locking functions.

Schlage ALX Series

Grade 2 | Modular Field-Configurable

Single patented chassis design supports most functions and all cylinder applications. In-field function change without ordering a new lock. Grade 1 compression springs prevent lever droop. Stainless steel latchbolt. 5-point spindle engagement. Field-selectable Vandlgard on all locking functions. Suites visually with ND Series levers.

Falcon T Series

Grade 1 | Extra Heavy Duty

Extra heavy-duty Grade 1 cylindrical lock with Pressure Release lever rotation standard to protect internal components under excessive force. Accepts any manufacturer's cylinder including Schlage, Sargent, and Corbin Russwin. Compression spring eliminates lever sag. 3-hour UL fire rated. Suited for government, military, institutional, and high-abuse applications.

The suiting strategy nobody explains clearly: The Schlage ND and ALX Series are specifically designed to suite visually. Use ND Grade 1 on exterior entry doors, secured offices, server rooms, and any opening requiring Grade 1 performance. Use ALX Grade 2 on storage, interior corridors, and lower-traffic interior doors where budget matters. Both series share the same lever designs and finishes, so the building maintains a consistent visual appearance while the hardware grade matches the security requirement of each individual opening.

Schlage ND Series: Understanding Function Codes Before Ordering Parts

The ND Series function code is the most critical piece of information needed before any parts order. The function code determines the chassis configuration, the spring cage type, and which trim components are compatible. Ordering a spring cage or adjustment plate from the wrong function creates a non-functional lock even when the physical parts fit together.

The Most Common ND Series Functions in Commercial Buildings

Function Code	ANSI Designation	How It Works	Typical Application
ND10	Passage	Both levers always free. No locking.	Closet doors, non-secure corridors
ND40	F76 Privacy	Inside push button locks outside lever. Emergency turn release from outside.	Restrooms, private offices, ADA-compliant privacy
ND44	Hospital Privacy	Indicator on inside shows room status. Key override from outside.	Healthcare patient rooms, behavioral health
ND50	F82 Entrance/Office	Push button locks outside lever until unlocked by key or inside lever.	Private offices, executive suites, retail entry
ND53	F109 Entrance	Turn/push button locks outside lever. Key required to unlock (inside lever does not release).	Secured offices, admin areas requiring key-only unlock
ND60	F88 Vestibule	Key in outside lever locks/unlocks it. Inside lever always free.	Vestibule entry doors, building lobby control points
ND70	F84 Classroom	Outside lever locked by key from outside only. Inside lever always free for immediate egress.	K-12 and higher ed classrooms (standard classroom lockdown)
ND73	F90 Corridor	Key retracts latch from outside. Inside lever always free.	Corridor doors on egress paths
ND80	F86 Storeroom	Outside lever always locked, key required. Inside lever always free.	Storage rooms, server rooms, secure supply areas

The Vandlgard function ordering mistake: ND70 (standard classroom) and ND94 (Vandlgard classroom) look identical in the door after installation. The parts are not interchangeable. If a building was specified with ND94 Vandlgard and a non-Vandlgard spring cage or chassis is ordered for a repair, the anti-ligature protection is compromised. Always pull the function code from the original specification or the label on the chassis before ordering any internal component.

Vandlgard: What It Is and Why It Matters for Parts Ordering

Vandlgard is a Schlage-patented feature that prevents forced lever torque from retracting the latch. On a standard ND Series lock, applying enough sustained downward force to the outside lever can, in some cases, retract the latch through the mechanical connection between the lever and the chassis. Vandlgard adds a clutch mechanism that breaks the lever-to-chassis connection before that force threshold is reached, while the lever can still operate normally when the door is unlocked.

Vandlgard function suffixes are ND91 (entrance/office), ND92 (entrance), ND94 (classroom), ND96 (storeroom), and ND97 (corridor). The Vandlgard function is field-selectable on the ALX Series, which means you can enable or disable it without ordering a different lock. On the ND Series, the Vandlgard feature is built into the function-specific chassis and cannot be retrofitted to a standard chassis without replacing the chassis assembly.

Most current institutional specifications for K-12, higher education, and healthcare require Vandlgard on classroom, storeroom, and secured office functions. If your building was originally specified with Vandlgard functions, all replacement parts must be sourced for the Vandlgard version of that function, not the standard version.

Every Replaceable Component in Commercial Cylindrical Locks

Chassis Assembly

The chassis is the internal mechanism housing that sits inside the door bore and contains the locking mechanism, the spindle engagement, and the spring return components. The chassis determines the function of the lock. It is not universal across functions on the ND Series. An ND50 chassis is configured differently from an ND70 or ND80 chassis, even though they look similar from the outside.

The Schlage ND Series chassis is zinc and steel with zinc dichromate plating for corrosion resistance. Door thickness accommodation is 1-3/4 inch standard with spacer kits available for 1-3/8 inch through 1-11/16 inch doors. The ALX Series uses a single chassis design that accommodates most functions, which is its key advantage for inventory management: one chassis type covers most of a building's lock schedule.

Replace the chassis when the internal mechanism fails to hold the locked state, when the spindle has developed severe play that cannot be addressed by spring cage replacement, or when a function conversion is required on the ALX Series. On the ND Series, function changes require a complete chassis replacement along with matching trim.

Spring Cage Assembly

The spring cage holds the lever in the horizontal position and provides the return force that brings the lever back after it is depressed. This is the most frequently replaced component on high-use cylindrical locks. Spring cage failure presents as lever sag, lever that does not return fully after being depressed, or a lever that rattles in the horizontal position.

Both Schlage ND and ALX Series use Grade 1 compression springs in the spring cage assembly specifically to resist lever droop under sustained use. The Falcon T Series uses a compression spring behind the cylinder that serves a similar function. When replacing a spring cage, confirm whether the outside or inside spring cage is failing before ordering. Both sides have their own spring cage assembly and they are not interchangeable with each other.

Diagnostic test before ordering a spring cage: Grip the lever and manually push it upward from below. A failing spring cage will feel as if it has almost no resistance before reaching the horizontal stop position. A functioning spring cage will feel firm from the moment you begin pushing upward. This test takes 5 seconds and confirms the spring cage diagnosis before ordering, preventing the more expensive mistake of ordering a full chassis assembly when only the spring cage needs replacement.

Latch Assembly

The latch is the spring-loaded bolt that extends from the door edge and clicks into the strike plate on the frame. On commercial cylindrical locks, the standard latch is a deadlatch, not a simple spring latch. A deadlatch has a plunger alongside the latch bolt that, when depressed by the strike plate on closing, prevents the latch bolt from being pushed back by a credit card or similar tool from the latch side of the door.

The Schlage ND Series default latch is part 13-247 with a 2-3/4 inch backset and 1-1/8 inch by 1-1/4 inch faceplate. The Falcon T Series default latch is part 23981145, a deadlatch with 2-3/4 inch backset and 1-1/8 inch by 2-1/4 inch square corner faceplate. Always confirm the backset (2-3/4 inch standard, 2-3/8 inch available) before ordering a latch replacement.

Latch failures on commercial cylindrical locks include the latch not retracting smoothly when the lever is depressed, the latch bolt not springing back after depression, and the deadlatch plunger binding or not depressing correctly. A latch that does not retract when the lever operates normally indicates the latch has failed, not the chassis. A latch that retracts but the lever feels stiff typically indicates the spring cage, not the latch.

Strike Plate

The standard ND Series strike is part 10-025, an ANSI curved lip strike, 1-1/4 inch by 4-7/8 inch, no box. The Falcon T Series default strike is part 5164, ANSI 1-1/4 inch by 4-7/8 inch with 1-3/16 inch lip length. The ALX Series uses the same ANSI curved lip strike as the ND Series.

Strike replacement is required when the strike is damaged by door misalignment, when the latch bolt fails to engage cleanly due to strike wear, or when a door handing change requires a different strike orientation. An ANSI box strike is used when hollow metal frame reinforcement is required. Always measure the existing frame cutout before ordering a strike replacement to confirm whether a standard or box strike fits the existing frame preparation.

Cylinders and Cylinder Formats

All three series at SecurityParts.com support multiple cylinder formats. Understanding the cylinder format installed is essential before ordering any cylinder replacement.

Cylinder Format	Abbreviation	Description	Best Application
Conventional	Standard	Standard pinned cylinder, 6-pin. Rekeyed by pulling and repinning.	Small to medium facilities with stable occupancy
Full-Size Interchangeable Core	FSIC	Core removed and replaced without disassembling the lock. Standard ANSI size.	Campuses and large facilities with frequent rekeying needs
Small Format Interchangeable Core	SFIC	Smaller core, used in Best SFIC and compatible systems.	Facilities with an existing SFIC key system
Less Cylinder (LC)	LC	Ordered without any cylinder. Customer supplies their own.	Facilities with proprietary key systems or restricted keyways

The Falcon T Series is specifically designed to accept cylinders from competing manufacturers including Sargent and Corbin Russwin in addition to Schlage. Some cylinders require modification of the lock for proper fit. Always specify the cylinder manufacturer when ordering a T Series with a non-standard cylinder.

Levers, Roses, and Trim

Levers on the ND Series are available in 9 designs including Athens, Rhodes, Sparta, Saturn, Broadway, Latitude, and Omega styles. The ALX Series shares these same lever designs, which is the visual suiting feature that allows mixed Grade 1/Grade 2 buildings to maintain a consistent appearance. Levers are pressure cast zinc finished to match mating parts.

The rose is the circular cover plate that conceals the chassis bore and the mounting screws on each side of the door. The ND Series rose is 3-7/16 inch standard diameter. The ALX Series rose is 3-7/16 inch standard, matching the ND Series for a seamless appearance when both are installed in the same building.

On the ALX Series, an optional break-away feature is available on Rhodes levers for most locking functions. When excessive torque is applied, the handheld portion of the lever breaks away from the shank, protecting the internal chassis from the torque damage that would otherwise require chassis replacement. This is a documented X Factor feature of the ALX Series and worth specifying on doors that receive frequent abuse.

Schlage ALX Series: The Modular Advantage and What It Means for Parts

The ALX Series modular design is the most significant feature for facilities managers and locksmiths who maintain large building inventories. A single chassis type supports most functions and all cylinder applications. This means a building can stock one chassis type and change functions in the field when a room's use changes, rather than ordering a new configured lock for every function change.

How In-Field Function Change Works

The ALX Series function is determined by a separate function kit that drops into the chassis. Changing from an ALX50 office function to an ALX70 classroom function requires the ALX70 function kit, not a new lock. The chassis stays. The lever stays. Only the function kit changes. This approach reduces inventory carrying costs, eliminates lead time waiting for factory-configured stock, and lets locksmiths carry a small number of kits on their truck rather than multiple configured lock units.

The installation sequence is designed for this: drop in the interior lever, install the function into the chassis, place the chassis in the door bore with the outside lever on the spindle, drop in the latch, drop in the cylinder or exterior function part. The separate compartment packaging keeps parts organized and prevents the small-part loss that often delays field service calls.

Captured Screws

The ALX Series uses captured screws in the latch, strike, and inside spring cage. Captured screws are retained in the component and do not fall out when the component is removed from the door. This eliminates the most common cause of rework on cylindrical lock service calls: small screws falling into wall cavities or onto floors during disassembly. On a building with dozens or hundreds of locks being serviced in a single shift, this feature has a real cumulative impact on service time.

Falcon T Series: The Multi-Cylinder Advantage and Pressure Release

The Falcon T Series occupies a distinct position in the cylindrical lock market. It is Grade 1 extra heavy-duty, designed for the highest-abuse institutional applications including government and military facilities, correctional housing, and any environment where locks receive deliberate physical attack rather than normal use.

Pressure Release Lever Rotation

The Falcon T Series includes Pressure Release lever rotation as a standard feature. When excessive torque is applied to the outside lever beyond the normal operating range, the lever rotates to a stop position that breaks the mechanical connection to the chassis rather than transmitting that force into the internal mechanism. This prevents the internal chassis damage that requires replacement after a forced entry attempt. The Pressure Release mechanism returns to normal operation after the excessive force is removed, without requiring any parts replacement, which is what makes it a standard feature rather than a consumable component.

Universal Cylinder Acceptance

The Falcon T Series is designed and marketed specifically on its ability to accept cylinders from competing manufacturers. In retrofit applications, this means a facility with an existing Corbin Russwin or Sargent key system can install T Series locks and retain their existing key system without rekeying. The T Series ships with 6-pin chambers drilled in 5-pin configuration as standard. 6-pin pinning is available at no extra cost when specified at ordering. This cylinder flexibility is the primary reason the T Series is specified on government and military retrofit projects where key system continuity is a security requirement.

Parts That Fail First: Realistic Replacement Frequency

Here is the actual field replacement order across all three series based on service call frequency.

1. Spring cage assembly. The most common replacement item on cylindrical locks with more than five years of high-traffic use. Lever sag, incomplete lever return, and lever rattle all trace to spring cage fatigue. Always try spring cage replacement before ordering a chassis.

2. Latch assembly. Latch bolts wear at the tip from repeated contact with strike plates that are slightly misaligned. The deadlatch plunger binding is a specific failure mode on latches that have been in service for more than 10 years without lubrication. Latches are inexpensive individual components and should be replaced rather than lubricated repeatedly once wear is visible on the bolt tip.

3. Cylinder. Cylinders wear from key insertion, especially in high-traffic entry doors. Signs of cylinder wear include a key that operates stiffly, a key that only works in one rotational direction, or a cylinder that spins without retracting the latch. FSIC and SFIC cylinders in interchangeable core systems can be replaced in seconds without disassembling the lock. Conventional cylinders require pulling the lock for cylinder removal.

4. Lever assembly. Levers bend, crack, or have their finish worn off from high-contact use. Lever replacement is cosmetic when the lock function is not impaired. Lever replacement is functional when a bent lever fails to return to horizontal or fails to fully depress the chassis mechanism on operation.

5. Strike plate. Strike wear accelerates when the door has settled and the latch bolt contacts the strike lip rather than entering the pocket cleanly. A worn or deformed strike allows a door that feels locked to actually be holdable open with sustained pressure. Strike replacement is inexpensive and should be done proactively when door alignment has been corrected.

What nobody else documents about ND Series manufacture dates: Schlage updated the ND Series manufacturing specifications on January 31, 2017. Components manufactured after that date have revised internal geometry in some function configurations. The service manual specifies two separate parts lists: one for locks manufactured before January 31, 2017, and one for locks manufactured after. Always check the manufacture date on the chassis label before ordering internal function components for a Schlage ND Series lock. Ordering a post-2017 spring cage for a pre-2017 chassis can result in a part that fits physically but does not function correctly.

How to Identify Your Lock Model Before Ordering

The model label is on the chassis body, visible when the inside lever and rose are removed. The label shows the series designation (ND Series, ALX Series, T Series), the function code (ND70, ALX50, T581), the finish code (626, 622, 619), and the handing if the lock is handed. For Schlage ND Series, the manufacture date is also on this label and is critical for selecting the correct parts revision.

If the label is worn or missing on an older ND Series unit, the function can often be determined by testing: the way the inside and outside levers behave without a key present tells you the function. A lever that is always free on one side and always locked on the other is storeroom (ND80). A lever that locks with a button from inside is entrance/office (ND50). A lever that locks from the outside with a key but the inside is always free is classroom (ND70).

For Falcon T Series locks, the model is stamped or cast into the chassis body itself. Common T Series model codes include T501 (passage), T521 (privacy), T561 (storeroom), T571 (classroom), and T581 (entrance/office).

SecurityParts.com organizes all three series in the cylindrical locks parts catalog by brand and model with interactive exploded diagrams. For Schlage commercial hardware parts including the ND Series, ALX Series, and Schlage B Series deadbolts, browse the Schlage catalog. For Falcon commercial hardware parts including the T Series and Falcon exit devices, browse the Falcon catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for Cylindrical Lock Parts

Series-specific diagrams, function code guidance, and same-day shipping on the components that get a building's locks back in service.

Function Code Guidance

We document which parts belong to which function. ND70 Vandlgard vs standard ND70. Pre-2017 vs post-2017 ND Series. These distinctions prevent wrong-part orders that cost time and freight.

Three Series Covered

Schlage ND Grade 1, Schlage ALX Grade 2, and Falcon T Series Grade 1 all on one catalog page with model-specific diagrams. One order covers a full building service call.

Same-Day Shipping

Most cylindrical lock parts ship same day from US warehouses. A failed classroom or storeroom lock is an operational and security issue that cannot sit open for a week.

Pre-Order Support

Call 845-935-0301 or use the contact page. Our team confirms series, function, manufacture date, and cylinder format before the order ships.

What Makes SecurityParts.com Different for Cylindrical Lock Parts

We document the Schlage ND Series January 31, 2017 specification change. Pre-2017 and post-2017 units require different internal components for some function configurations. No other parts supplier explains this before the order is placed.
We distinguish between standard function codes and Vandlgard function codes. ND70 and ND94 are not interchangeable. Parts are listed under the correct function designation so the Vandlgard protection is not inadvertently removed during a repair.
The ALX Series modular function-change advantage is documented on our model pages. Facilities managers who do not know about the in-field function kit change continue to order full configured locks when only the function kit is needed.
We carry Schlage cylindrical lock parts alongside Schlage L Series mortise lock parts, Schlage B Series deadbolt parts, and Von Duprin exit device parts. One order services the complete building opening.
Same-day shipping from US warehouses on stocked parts. Free shipping on orders over $450.
30-plus years of commercial door hardware experience behind every pre-order compatibility confirmation.

Related Parts and Products at SecurityParts.com

Cylindrical locks are part of a complete commercial door opening. The complete assembly on most institutional doors also includes a door closer, exit device, or mortise lock at higher-security openings.

For Schlage L Series and Falcon MA Series mortise lock parts on high-security and main entry doors in the same facility, browse the mortise locks catalog. For Schlage B Series deadbolt parts on doors that use a deadbolt alongside a cylindrical lock, browse the deadbolts catalog. For LCN door closer parts on any door with automatic closing hardware, browse the door closers catalog. For Von Duprin and Falcon exit device parts on egress doors in the same building, browse the commercial exit devices catalog. For Von Duprin electric strike parts on access-controlled entries, browse the electric strikes catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex in a single session.

Frequently Asked Questions About Commercial Cylindrical Lock Parts

What cylindrical lock series does SecurityParts.com carry parts for?

SecurityParts.com carries replacement parts and interactive diagrams for the Schlage ND Series Grade 1, Schlage ALX Series Grade 2, and Falcon T Series Grade 1 cylindrical locks. All three series have dedicated model pages with exploded diagrams organized by series and function code for visual part confirmation before ordering.

What is the difference between the Schlage ND Series and ALX Series?

The ND Series is Grade 1 with 24 mechanical functions and beyond-Grade-1 strength ratings (3,100 in-lb lever torque resistance). The ALX Series is Grade 2 with a single modular chassis that allows in-field function changes without ordering a new lock. Both use Grade 1 compression springs and share the same lever designs and finishes for visual suiting in mixed-grade buildings.

What does the Schlage ND function code mean?

The ND function code identifies how the lock operates on each side. ND10 is passage. ND40 is privacy. ND50 is entrance/office with push button. ND70 is classroom with outside key lock only. ND80 is storeroom with always-locked outside lever. Vandlgard versions add anti-ligature protection: ND94 is Vandlgard classroom, ND96 is Vandlgard storeroom. Always confirm the function code before ordering chassis, spring cage, or trim components.

What is Vandlgard on the Schlage ND Series?

Vandlgard is a Schlage feature that prevents forced lever torque from retracting the latch. It adds a clutch mechanism that breaks the lever-to-chassis connection under excessive force while allowing normal lever operation when the door is unlocked. Vandlgard functions are designated with specific codes: ND91, ND92, ND94, ND96, ND97. Parts for Vandlgard functions must be ordered for the correct Vandlgard version, not the standard function version.

Can the Falcon T Series accept any manufacturer's cylinder?

Yes. The Falcon T Series is designed to accept cylinders from Schlage, Sargent, Corbin Russwin, and other manufacturers. The cylinder removes easily for quick re-keying. Some cylinders require modification to the lock for proper fit. Always specify the cylinder manufacturer when ordering. Standard configuration ships with 6-pin chambers pinned in 5, with 6-pin pinning available at no extra cost when specified.

What causes cylindrical lock lever sag and how do I fix it?

Lever sag is caused by spring cage fatigue or spindle wear. Try the diagnostic: grip the lever and push it upward from below. Minimal resistance confirms a failing spring cage. Replace the spring cage assembly first before assuming the chassis has failed. Both Schlage ND and ALX Series use Grade 1 compression springs to resist this failure. Falcon T Series uses a compression spring behind the cylinder that virtually eliminates lever sag in normal service.

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Von Duprin Electric Strike Parts: 5100, 6100, 6200 and 6300 Series Complete Guide Thursday, June 18, 2026

Von Duprin electric strikes replace the fixed strike plate on a door frame and allow remote unlocking via access control. The 5100 is medium-duty, the 6100 and 6200 are heavy-duty stainless steel, and the 6300 is a fire-rated no-cut surface-mounted rim strike. Parts that fail most often are the solenoid assembly, the keeper, and the faceplate. Solenoid kits are voltage-specific: part 050237 for 12VDC, part 050240 for 24VDC. Always confirm wire color before ordering a replacement solenoid: black wires mean 24VDC, yellow wires mean 12VDC. Getting this wrong destroys the solenoid immediately.

Electric strikes are the most widely replaced access control hardware component in commercial buildings. Unlike mechanical strike plates, which are passive, an electric strike has a moving keeper, a solenoid, a spring, and electrical connections that all wear, corrode, and fail over time. The Von Duprin electric strike series is the most common in institutional and commercial buildings across North America, installed alongside Von Duprin and Falcon exit devices on virtually every category of egress door.

When one fails, you need the right part fast. A failed electric strike on a secured entry either leaves a door that cannot be locked or a door that cannot be opened from a credential. Both are problems that shut down operations. This guide covers every series, every replaceable component, the fail safe vs fail secure distinction that creates the most field confusion, and the exact diagnostic steps that identify the failed component before you order anything. Browse the complete Von Duprin electric strikes parts catalog at SecurityParts.com for model-specific diagrams on every series.

4 Active Von Duprin electric strike series: 5100, 6100, 6200, 6300

17 Configurations available in the 6200 Series alone

1,500 lbs Static holding force on the 6300 Series

UL 10C 3-hour fire door rating on the 6300 Series (fail secure only)

How Von Duprin Electric Strikes Work

A standard mechanical strike plate is fixed. The latch bolt from the door lock clicks into it and stays. An electric strike replaces that fixed plate with a mechanism that includes a movable keeper, called the lip or gate. When the door is closed, the keeper is rigid and holds the latch bolt securely. When an authorized credential or button press energizes the solenoid, the keeper pivots and allows the latch bolt to pass through, letting the door open without anyone touching the lock on the door.

This is the design advantage over fully electrified locksets. The mechanical lock on the door stays completely unchanged. The electric strike handles the access control function at the frame. You can retrofit access control onto existing doors with mechanical locks without replacing the lock itself, which is significantly less expensive and less invasive.

The solenoid is the electrical component that drives the keeper. When powered, it either locks or unlocks the keeper depending on the fail mode configuration. The solenoid connects to an access control panel output relay, a door release button, or a credential reader. The electrical connection is low voltage, typically 12VDC or 24VDC DC, and the wire run from the panel to the frame is carried through the wall or concealed in the frame cavity.

The Four Active Von Duprin Electric Strike Series

5100 Series: Medium Duty

An all-in-one boxed solution for rim exit device applications. The 5100 is the entry-level Von Duprin electric strike. Parts include the faceplate package (standard 4-7/8 inch or long 7-11/16 inch), screw package, mounting package, and solenoid replacement kit. The solenoid kit for the 5100 (part 050034) is specific to this series and includes the plunger and plunger spring as a single kit.

6100 Series: Heavy-Duty Rim

Heavy-duty stainless steel construction for rim exit device applications. The 6100 is the standard specification for rim exit device openings in commercial and institutional buildings. Compatible with Von Duprin 98/99, 22, 33/35A, 75, 78, 88, and 55 Series rim devices, and Falcon 19, 24, and 25 Series rim devices. Uses the 6000 Series solenoid kits (050237, 050239, 050240) shared with the 6200 series.

6200 Series: Heavy-Duty, 17 Configurations

The most versatile series in the Von Duprin electric strike lineup. 17 configurations cover cylindrical lock, mortise lock, and rim exit device applications for new construction and retrofit. Integrated faceplates provide cleaner aesthetics. Uses Type A, Type B, Type C, and Offset Box assemblies depending on configuration. The preferred series for new construction projects with frame preparation in the door schedule.

6300 Series: Fire-Rated No-Cut

Surface-mounted rim strike requiring no frame cutting or modification. Attaches directly to the door frame stop face. Compatible with most rim exit devices from Von Duprin, Falcon, and other manufacturers. Fail secure only. UL 10C 3-hour fire-rated. Static strength 1500 lbs. Dynamic strength 70 ft-lbs. The correct specification when frame modification is not possible on aluminum storefronts or retrofit projects.

Fail Safe vs Fail Secure: The Most Important Decision Before You Order

This is the distinction that causes more wrong-part orders and post-installation failures on electric strikes than any other single factor. Getting it backwards means the door either cannot be secured or cannot be exited, depending on which way it is wrong.

Fail Safe (FS): Unlocks When Power is Lost

In a fail safe configuration, the strike is continuously powered to stay locked during normal operation. When power is cut, whether from a power outage, a tripped breaker, or a fire alarm activation, the solenoid releases and the keeper becomes free. The door can be pushed open without any credential. This is the required configuration for any fire-rated egress door where free exit must be maintained at all times, including during a power failure. It is also required for egress paths covered by IBC Chapter 10 where electronic locking is permitted only if the lock releases on fire alarm.

Fail Secure (FSE): Stays Locked When Power is Lost

In a fail secure configuration, the strike is energized only momentarily to unlock. During a power failure, the keeper remains rigid and the door cannot be opened without a credential. This is the correct configuration for server rooms, exterior building entries, secure storage areas, and any location where security must be maintained even during a power outage. The Von Duprin 6300 Series is fail secure only, which is required to achieve its UL 10C fire door rating.

Fire door rule that competitors rarely explain clearly: On a fire-rated egress door, a fail secure electric strike is only permitted if it is connected to the building fire alarm system and releases automatically on alarm activation. Using a fail secure strike on a fire door without fire alarm integration is a NFPA 101 and IBC code violation. The 6300 Series ships fail secure but requires fire alarm integration on fire-rated assemblies.

How to Identify the Fail Mode on an Installed Strike

There is a reliable field test that works on any installed electric strike. Remove power from the strike. Try to open the door by pressing or pulling the exit device. If the door opens without power, the strike is fail safe. If the door stays locked without power, the strike is fail secure. This takes 30 seconds and eliminates any ambiguity from worn or missing labels on the hardware.

For Von Duprin 6100 and 6200 series units, the fail mode can be field-converted between fail safe and fail secure by repositioning the actuator inside the strike body without replacing the solenoid. The 050237 (12VDC) and 050240 (24VDC) solenoid kits are field-selectable between both modes. This conversion capability is one of the most valuable features of the 6000 Series and is documented in the service manual diagrams available on the SecurityParts.com model pages.

Every Replaceable Component in Von Duprin Electric Strikes

Solenoid Assembly: The Most Commonly Replaced Component

The solenoid is the electromagnetic coil that converts electrical current into the mechanical movement that drives the keeper. It is the component under the most electrical and thermal stress in normal operation and the one that fails most often in high-use installations.

Von Duprin 6000 Series solenoid kits are voltage-specific. This is the single most important detail in electric strike parts ordering.

Part Number	Voltage	Compatible Series	Fail Mode	Wire Color
050034	Varies	5100 Series only	Series-specific	Check label
050237	12VDC	6100 and 6200 Series	Field selectable FS/FSE	Yellow wires
050239	16VDC	6100 and 6200 Series	Field selectable FS/FSE	Check label
050240	24VDC	6100 and 6200 Series	Field selectable FS/FSE	Black wires

Never swap solenoids by appearance alone. The 12VDC and 24VDC solenoid kits for the 6000 series look physically identical. The only reliable distinguisher is the wire color: yellow wires are 12VDC, black wires are 24VDC. Installing a 24VDC solenoid on a 12VDC system causes slow, incomplete keeper movement. Installing a 12VDC solenoid on a 24VDC system burns the coil immediately and permanently. Always verify wire color and system voltage before ordering.

Box Assembly

The box assembly is the metal housing that mounts in the door frame cutout and contains the solenoid, keeper spring, and electrical components. Von Duprin 6100 and 6200 series strikes use several box assembly types depending on the frame configuration and application.

Type A Box: Standard box assembly for typical hollow metal frame applications. The most common configuration.

Type B Box: Used on 6200 series mortise and cylindrical applications with specific frame geometry requirements. Type B Box images in the parts manual confirm the installation orientation.

Type C Box: Used on 6100 and 6200 series applications requiring a different frame depth. Available in DS (door status) and DS-LC (door status with latch check) versions that add monitoring capability to the box assembly without a separate monitor switch.

Offset Box: For frame applications where the standard solenoid position creates a conflict with the frame construction. The offset box repositions the solenoid 90 degrees from the standard orientation.

Faceplate Package

The faceplate is the visible plate on the frame face that covers the strike body and presents the keeper opening. Von Duprin 5100 series faceplate packages are available in three configurations.

Part 050031: Standard 4-7/8 inch faceplate package for typical commercial frame applications.

Part 050032: Round corner 4-7/8 inch faceplate for frames with rounded corners or decorative trim.

Part 050033: Long 7-11/16 inch faceplate for applications requiring extended coverage of the frame face.

Faceplate packages include the faceplate, wire nuts, and all fasteners required for installation. Always specify the finish when ordering, as faceplates are available in multiple finishes and the finish code is required for the correct part.

Keeper (Strike Lip)

The keeper, also called the strike lip or gate, is the moving component that holds the latch bolt when locked and releases when the solenoid is activated. The keeper takes direct mechanical contact from the latch bolt on every door close, which makes it a wear component on high-traffic openings. The correct keeper for each 6200 series model varies because the lip design differs between cylindrical and mortise applications. Always confirm the exact strike model when ordering a keeper replacement.

A keeper with visible wear marks, deformation, or a loose pivot shows up as inconsistent latching or a door that does not feel firmly latched even when the access control system shows it as locked. Replacing the keeper alone is significantly less expensive than replacing the full strike assembly when the box and solenoid are still functional.

Screw Package and Mounting Package

Screw Package (PKGSCR.1003 for US32D finish, PKGSCR.1004 for black finish): Includes the #10-24 5/16 inch UFPHMS, 12-24 1/2 inch UFPHMS, 12-14 1 inch UFPHWS, and blue wire nut. Required when reinstalling a strike with damaged or missing original hardware.

Mounting Package (PKGMTG.1004 for US32D, PKGMTG.1005 for black): Includes the mounting tab zinc, mounting tab shim nylon, and 10-24 1/2 inch UFPHMS. The mounting tab allows the strike to be positioned horizontally in the frame cutout for precise latch alignment.

Solenoid Washer and Solenoid Spring

Part 964037 Solenoid Washer: Seats the solenoid in the box assembly and ensures proper alignment of the plunger. A missing or damaged washer causes solenoid misalignment that results in incomplete keeper movement even when the solenoid itself is functional.

Part 968713 Solenoid Spring: Returns the plunger to its resting position after each activation cycle. Spring fatigue is a legitimate failure mode on doors that are released hundreds of times per day. Symptoms include a keeper that activates correctly but returns slowly or incompletely to the locked position, creating a security gap on fail secure applications.

The 6300 Series: What Makes It Different and When to Use It

The 6300 is the only Von Duprin electric strike that requires no frame cutting. Every other series in the Von Duprin lineup requires cutting or modifying the door frame to recess the strike body. The 6300 mounts surface on the frame stop face, which makes it the correct specification in three specific situations where no other series works.

When the 6300 Is the Right Choice

Aluminum storefront retrofit: Aluminum storefronts have thermal breaks inside the frame profile. Cutting into the frame to recess a strike destroys the thermal break and compromises the building envelope. The 6300 mounts on the frame face without cutting, preserving the thermal break.

Historic preservation projects: Frame modification is not permitted on many historic building projects. The 6300 provides electrified access control without permanent modification to the original frame.

Tenant fit-out on leased space: When a tenant cannot modify the building structure, the 6300 delivers access control capability that can be removed at lease end without leaving a frame cutout.

6300 Key Specifications

The 6300 is fail secure only. It achieves UL 10C 3-hour fire door rating in the fail secure mode. UL 1034 burglary-resistant and UL 294 access control system listed. Static strength is 1500 lbs. Dynamic strength is 70 ft-lbs. Compatible with 12VDC or 24VDC using the plug-in voltage connectors shipped with the unit. Two voltage connectors ship in the package and only the correct one for the available system voltage is used.

6300 Exit Device Compatibility

The 6300 works with a broad range of rim exit devices. Von Duprin compatibility includes the 22/22-F Rim, 33A/35A Rim, 55 Rim, 88/88-F Rim, and 98/99/98-F/99-F Rim. Falcon compatibility includes the 19/19-F Rim, 24/24-F Rim, and 25/25-F Rim. The entry buzzer accessory (part 050242, for fail secure applications) is also compatible with the 6300 and is wired in parallel with the circuit to sound an audible alert when the strike is unlocked remotely.

6300 field fact that nobody documents: The 6300 is designed for "indoor use only" unless it is not continuously exposed to an outdoor environment. This means an exterior application where the 6300 is in a covered vestibule or recessed alcove is acceptable. A 6300 on a fully exposed exterior frame in a coastal or high-humidity environment will have a significantly shorter service life due to accelerated corrosion of the surface-mounted components. For fully exposed exterior applications, the 6100 or 6200 series with proper frame prep is the correct specification.

Troubleshooting Von Duprin Electric Strike Problems

Before ordering any replacement part, run this diagnostic sequence. Half of all reported electric strike failures are not component failures at all. They are power delivery problems, wiring issues, or latch alignment problems that require no parts whatsoever.

Verify Voltage at the Strike Terminals

Use a multimeter and confirm that the correct voltage is arriving at the strike terminals during an access grant signal. For 12VDC systems, confirm 12VDC plus or minus 10 percent. For 24VDC systems, confirm 24VDC plus or minus 10 percent. If voltage is not present at the strike terminals, the problem is upstream in the access control panel, the wiring run, or the power supply. No hardware replacement fixes a wiring or panel problem.

Confirm Voltage Matches the Solenoid

Check the wire color inside the strike. Black wires indicate 24VDC. Yellow wires indicate 12VDC. Confirm that the system voltage matches the solenoid voltage. A 12VDC solenoid receiving 24VDC burns immediately. A 24VDC solenoid on a 12VDC system will not actuate fully. This is the most common cause of a brand-new or recently serviced strike that still does not function correctly after replacement.

Eliminate Frame Pre-Load

Remove the strike from the frame completely. Apply the correct voltage directly to the strike terminals and observe the keeper. There must be 1/32-inch clearance between the latch bolt and the keeper lip when installed. If the latch bolt presses against the keeper, an internal protrusion prevents the slider from moving even when the solenoid activates correctly. If the strike works outside the frame but not inside it, the problem is latch bolt alignment, not the strike itself.

Check the Fail Mode Configuration

If the strike operates oppositely from what is expected, the wrong fail mode is specified. If the door unlocks when it should stay locked during a power cut, the strike is fail safe when it should be fail secure. If the door stays locked when it should free-exit during a power cut, the reverse is true. For 6100 and 6200 series units, the fail mode can be field-converted by repositioning the actuator without replacing the solenoid.

Test the Solenoid Directly

Apply the correct voltage directly to the strike terminals with the unit out of the frame. If the keeper does not move with correct voltage and no pre-load, the solenoid has failed and requires replacement. Confirm the solenoid spring and white washer are inside the solenoid body and that the plunger moves freely before concluding the solenoid has failed. A plunger that is stuck or binding due to debris may restore function after cleaning without requiring replacement.

Entry Buzzer and AC Rectifier Accessories

Two accessories for the Von Duprin electric strike series are commonly missing from parts orders because they are rarely described in detail anywhere.

Entry Buzzer (Part 050242)

The entry buzzer is available for fail secure strike applications only. It mounts in the door frame and wires in parallel with the strike circuit. When the strike is energized to unlock (in a fail secure configuration, this is when the door is being released for entry), the buzzer sounds an audible alert to notify the person inside that someone is requesting entry. This is the standard specification for any secured entry point where the occupant should be aware of remote unlock events. The buzzer is not compatible with fail safe strikes because in fail safe, the strike is powered continuously and the buzzer would sound constantly.

AC Rectifier Kits (SO12 and SO24)

Von Duprin electric strike solenoids are DC devices. Some access control panels and power supplies output AC rather than DC. The SO12 kit converts 12VAC to 12VDC for the strike solenoid. The SO24 kit converts 24VAC to 24VDC. These kits are field-installable and plug in-line to the solenoid wiring. If a newly installed strike chatters, hums, or activates erratically despite correct voltage at the terminals, the panel may be outputting AC to a DC solenoid. The SO12 or SO24 rectifier kit is the correct fix, not a solenoid replacement.

How to Order Von Duprin Electric Strike Parts Without a Return

Three pieces of information are required before any electric strike parts order.

1. The exact series and model number. The model number is stamped or labeled on the faceplate or on the box housing. Von Duprin 4200, 5100, 6100, 6200, 6300, and 6400 series all use different part numbers for components with the same name. A solenoid kit for the 5100 series (part 050034) is completely different from the 6000 series kit (050237 or 050240). Order by series designation, not by component name.

2. The system voltage. Confirm whether the access control panel outputs 12VDC or 24VDC at the lock output. This determines whether you order the 050237 (12VDC) or 050240 (24VDC) solenoid kit. If uncertain, measure with a multimeter during an access grant signal before ordering.

3. The fail mode. Confirm fail safe or fail secure before ordering any solenoid, box assembly, or complete strike. Solenoid parts for fail safe and fail secure configurations on the same series are not always interchangeable. The 6100 and 6200 series field-selectable kits cover both modes with the same part number, but the 6300 is fail secure only and no conversion is available.

SecurityParts.com organizes the complete Von Duprin electric strikes parts catalog by series with interactive exploded diagrams. You confirm the exact component visually before ordering. Pre-order support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for Von Duprin Electric Strike Parts

Diagram-based identification, individual part stocking, and same-day shipping on components that cannot wait.

Diagram-Based Part ID

Every Von Duprin electric strike model page has an interactive exploded diagram. See exactly where each component sits before adding it to cart. No guessing from text descriptions.

Correct Solenoid Guidance

We document the wire color and voltage difference between the 050237 and 050240 kits. Ordering the wrong voltage destroys the solenoid. We prevent that before the order ships.

Same-Day Shipping

A failed electric strike on a secured entry or egress path cannot wait a week. Most Von Duprin electric strike components ship same day from US warehouses.

Full Series Coverage

5100, 6100, 6200, and 6300 series all on one catalog page. Browse by series and model. One order covers the complete opening.

What Makes SecurityParts.com Different for Electric Strike Parts

We document the wire color difference between 12VDC and 24VDC solenoid kits (yellow vs black) so technicians do not destroy a new solenoid with the wrong voltage. No other parts supplier explains this upfront.
We explain the field conversion between fail safe and fail secure on 6100 and 6200 series units, which eliminates the need to order a whole new strike when only the fail mode needs to change.
We stock individual components including solenoid kits, faceplate packages, screw packages, mounting packages, solenoid washers, and solenoid springs. You do not need to buy a complete strike assembly to replace a single worn keeper or failed solenoid spring.
The 6300 outdoor limitation (indoor use only unless not continuously exposed) is documented on our model pages. Ordering the wrong strike for a fully exposed exterior application is prevented at the selection stage.
We carry Von Duprin electric strikes alongside Von Duprin exit device parts, LCN door closer parts, and exit alarm parts. One order services the complete door opening.
Same-day shipping on stocked parts from US warehouses. Free shipping on orders over $450.

Related Parts and Products at SecurityParts.com

Von Duprin electric strikes are always part of a larger door opening assembly. The complete opening typically includes an exit device, a door closer, and sometimes a cylindrical or mortise lock on the same door.

For Von Duprin and Falcon exit device parts on the same door, browse the commercial exit devices catalog. The electric strike and exit device on a rim-style opening must be matched for latch bolt geometry and throw depth. For Von Duprin parts by series including the 98/99, 22, 33/35A, 75, 88, and Guard-X, browse the Von Duprin brand catalog. For LCN door closer parts on the same commercial door, browse the door closers catalog. For Schlage L Series and Falcon MA Series mortise lock parts on high-security doors in the same facility, browse the mortise locks catalog. For Von Duprin Guard-X and Detex exit alarm parts on secondary exits, browse the exit alarms catalog.

Browse the complete all products and parts catalog to source across all brands in a single session.

Frequently Asked Questions About Von Duprin Electric Strike Parts

What Von Duprin electric strike series does SecurityParts.com carry parts for?

SecurityParts.com carries replacement parts and interactive diagrams for the Von Duprin 5100 Series medium-duty electric strikes, 6100 Series heavy-duty rim exit strikes, 6200 Series heavy-duty strikes for mortise, cylindrical, and rim applications, and 6300 Series fire-rated surface-mounted rim strikes. All four series have dedicated model pages with exploded diagrams for visual part identification before ordering.

What is the difference between fail safe and fail secure on a Von Duprin electric strike?

Fail safe unlocks when power is removed. Required on fire-rated egress doors where free exit must always be maintained. Fail secure stays locked when power is removed. Required on secured perimeters where security must be maintained during a power outage. The 6300 Series is fail secure only. The 6100 and 6200 series solenoid kits (050237 for 12VDC, 050240 for 24VDC) are field-selectable between both modes.

What solenoid kit do I need for a Von Duprin 6100 or 6200 series electric strike?

Part 050237 for 12VDC systems. Part 050240 for 24VDC systems. Part 050239 for 16VDC AC rectifier applications. Confirm wire color before ordering: yellow wires mean 12VDC, black wires mean 24VDC. Installing the wrong voltage solenoid burns the coil immediately on 24V systems or causes incomplete activation on 12V systems.

Why is my Von Duprin electric strike not unlocking when power is applied?

Run the diagnostic in order: confirm correct voltage at the terminals, confirm wire color matches system voltage, remove the strike from the frame to eliminate latch pre-load, test the keeper movement with correct voltage applied directly. If the keeper moves outside the frame but not inside, latch alignment is the problem. If the keeper does not move even with no frame pre-load and correct voltage, replace the solenoid kit.

What is the difference between the Von Duprin 6100 and 6200 series electric strikes?

The 6100 is designed specifically for rim exit device applications. The 6200 offers 17 configurations for cylindrical lock, mortise lock, and rim exit device applications, making it the most versatile series in the lineup. The 6200 uses integrated faceplates for cleaner aesthetics and is preferred for new construction where frame preparation is part of the original door schedule.

What is the Von Duprin 6300 and when should I use it?

The 6300 is a fire-rated, surface-mounted rim electric strike that requires no frame cutting. It mounts on the frame stop face and is compatible with most rim exit devices from Von Duprin, Falcon, and other manufacturers. Fail secure only. UL 10C 3-hour fire-rated. Use it when retrofitting access control on aluminum storefronts, historic preservation projects where frame modification is not permitted, or tenant fit-outs where the frame cannot be permanently modified.

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LCN Door Closer Parts: 4040XP, 4000 Series and Complete Service Guide Wednesday, June 17, 2026

LCN door closers use a rack-and-pinion mechanism with hydraulic fluid to control closing speed. The 4040XP is the institutional flagship with cast-iron cylinder, forged steel arm, Liquid X all-weather fluid, Green Dial spring sizing (1 through 6, ships at size 3), and four adjustment valves. Arms are model-specific and not interchangeable between series. A leaking cylinder cannot be refilled in the field. If the sweep valve is fully open and the door still slams, replace the cylinder assembly. Always use the model number stamped on the body, not the body's physical appearance, to identify the correct replacement part.

LCN has manufactured commercial door closers since 1877. Walk through any school, hospital, government building, or office in North America and you will almost certainly pass an LCN closer. They are on more institutional doors than any competing brand, which also means they generate more field service calls than any competing brand.

Most of those service calls come down to the same handful of failures. Hydraulic leaks. Stripped spindles. Broken or bent arms. Valves that no longer hold their settings. Getting the right replacement part fast without a wrong-part return is what determines whether the door is back in service today or next week. This guide covers the complete LCN door closer parts catalog at the field level, starting with what actually fails and ending with how to order correctly.

1877 Year LCN began manufacturing door closers

2M ANSI Grade 1 rated cycles for the 4040XP

Size 1-6 Spring power range on the 4040XP Green Dial

30 Yrs Limited warranty on the LCN 4040XP

How LCN Door Closers Work

Every LCN surface-mounted closer operates on the same fundamental principle: a coil spring stores energy when the door opens and releases it to close the door, while hydraulic fluid flowing through calibrated valves controls the speed of that release. Inside the cast-iron body, a rack gear acts as a piston. The pinion shaft connects the rack to the arm outside. When you open the door, the arm rotates the pinion, which drives the rack against the spring. Hydraulic fluid is displaced from one side of the rack to the other through small internal channels with adjustable valve screws.

This is the mechanism that every valve adjustment interacts with. The sweep valve controls how fast fluid moves during the main arc. The latch valve controls the final 10 to 15 degrees. The backcheck valve restricts fluid movement when the door is pushed open hard, creating resistance that protects walls and hardware. None of these valves add or remove force. They only regulate the speed of fluid transfer. If the fluid is gone, no valve setting can correct a slamming or drifting door.

LCN fills every 4040XP with Liquid X all-weather hydraulic fluid, which maintains consistent viscosity from -30 degrees F to 120 degrees F for manual closers. This temperature stability is why the 4040XP performs correctly on exterior doors and vestibules where temperature swings are significant. Standard hydraulic fluid thins in summer heat and causes uncontrolled fast closing on exterior applications.

LCN Series Carried at SecurityParts.com

SecurityParts.com stocks replacement parts and interactive diagrams for every major LCN series currently in commercial service. Understanding which series is installed is the first step before any parts order. Browse the full LCN parts catalog to navigate by series.

LCN 1000 Series

Surface-mounted closers for light commercial and residential applications. Economy grade. Parts include cylinder assemblies, arm components, and cover plates.

LCN 4000 / 4040XP Series

The institutional flagship. Heavy-duty cast-iron body, Liquid X fluid, Green Dial, 30-year warranty. The most widely installed commercial closer in North America.

LCN 4210 / 4510 Smoothee

Parallel arm only. The heaviest-duty LCN surface closer. Designed exclusively for push-side parallel arm applications on very high-traffic exterior doors.

LCN 2030 / 5030 / 6030 Series

Heavy-duty concealed closers for high-traffic entrances where surface hardware is architecturally unacceptable. Body conceals in the frame transom.

LCN 3030 / 3130 Series

Medium-duty concealed closers. The 3030 uses an exposed double-lever arm. The 3130 uses a concealed track arm for minimal visible hardware.

LCN 2010 / 5010 Series

Concealed closers that hide both the body in the frame and the track in the door. Used on high-end institutional openings where no hardware is visible.

LCN Sentronic Series

Electromagnetic hold-open closers (3130SE, 4040SE, 4310ME, 4410ME). Integrates with fire alarm systems to hold fire and smoke barrier doors open and release automatically on alarm activation.

LCN Auto Equalizer Operators

Low-energy automatic operators (2610, 4810, 4820, 4840, 4630, 4640). For ADA-accessible entrances requiring hands-free push-pad or sensor activation.

The LCN 4040XP: Every Component Explained

Cylinder Assembly (4040XP-3071)

The cylinder is the heart of the 4040XP. It contains the spring, rack gear, pinion shaft, bearings, and all hydraulic fluid passages. LCN uses a high-strength cast-iron body with a 1.5-inch diameter piston. The pinion shaft on the 4040XP measures 3/4 inch in diameter, which is larger than the original 4040, giving 44 percent more bearing load capacity. This enlarged shaft is the main structural improvement of the XP designation.

When the cylinder leaks, the entire assembly must be replaced. LCN does not supply rebuild seals for field refilling. Trying to top up hydraulic fluid in a leaking 4040XP body does not restore function because the seal that failed will continue to fail. The correct repair is ordering a replacement cylinder assembly (part 4040XP-3071) matched to the finish code on the existing unit.

One of the most common field mistakes: Attempting to refill or re-seal an LCN cylinder in the field. LCN closers are not designed for this. Once the cylinder body leaks, order a replacement. Every minute spent trying to patch a leaking body is time the door is operating without hydraulic control.

Arm Assembly and Arm Configurations

The arm connects the closer body to the door or frame and is the component most likely to be physically damaged in service. LCN produces several arm configurations for the 4040XP. Choosing the wrong configuration for the mounting position is the most common installation error in the field.

Arm Type	Part Suffix	Mounting Position	Best Application
Regular arm	-3077	Hinge side (pull side) or top jamb (push side)	Interior commercial doors, standard offices, corridors
Parallel arm with PA bracket	-RW/PA	Push side only, arm folds parallel to frame	Exterior commercial doors, low-profile push-side requirement
Extra duty arm (EDA)	-EDA	Hinge side or push side	High-abuse applications, schools, correctional facilities
Hold-open arm	-3049H	Hinge side or top jamb	Openings that must stay open at a fixed position
Cush N Stop arm	-CUSH	Hinge side or top jamb	Replaces mechanical door stop; built-in cushion stop function
Track arm (4040T)	-4040T	Hinge side or push side with track rail	Variable hold-open position; hospital corridors, loading docks

Parallel arm sizing rule no one else explains: Parallel arm mounting is mechanically less efficient than regular arm mounting. LCN specifies adding one full spring size to every sizing table recommendation when using parallel arm. If the chart says size 3 for a regular arm on a 36-inch door, use size 4 for the same door in parallel arm. Skipping this adjustment is why parallel arm installations often fail to latch consistently.

The Green Dial Spring Power System

The LCN Green Dial is a patented visual indicator on the spring tube that shows the current spring power setting from size 1 through size 6. The 4040XP ships set to size 3, which provides adequate closing force for a standard 36-inch interior door in a regular arm configuration. Adjust with the 5/32-inch hex screw on the spring tube: clockwise increases spring power, counterclockwise decreases it.

Spring sizing is not guesswork. LCN publishes a sizing chart based on door width and mounting configuration. For interior doors up to 36 inches, size 3 is the starting point. For exterior doors from 36 to 48 inches, size 4 to 5. For exterior doors over 48 inches or high wind exposure locations, size 5 to 6. After setting the spring size, always verify ADA compliance with a calibrated force gauge. The dial setting is a starting point, not a guarantee of the actual force measured at the door face because door weight, hinge friction, weather seal drag, and threshold resistance all affect the actual opening force independently of the spring setting.

The Four Valve Adjustments

The 4040XP has four adjustment screws on the face of the closer body, labeled for identification. Each controls a different phase of the door's movement. Use a 3/32-inch hex key for the sweep and latch valves. Use the 5/32-inch hex key for the spring power screw. Turn clockwise to decrease speed (slow down), counterclockwise to increase speed.

Valve	Controls	ADA Requirement	Common Problem When Wrong
Sweep (S)	Door movement from fully open to 10-15 degrees from latch	Minimum 5 seconds from 90 degrees to latch point	Too fast: door slams. Too slow: door drifts and fails to latch in drafty conditions
Latch (L)	Final 10-15 degrees before the door fully closes	Must engage latch bolt positively on every close	Too slow: door does not latch. On fire doors this is a NFPA 80 compliance failure
Backcheck (B)	Resistance when door is opened past 70-75 degrees	No direct ADA requirement	Too tight: door feels stuck when opening. No backcheck: hardware damage from hard opens
Delayed Action (D)	Pause at 70 degrees before sweep phase begins	Recommended for ADA-accessible entrances	Only available on CYLDEL-configured units. Not present on standard 4040XP

Field rule: Never open any valve more than 1.5 full turns from the fully closed position. Opening a valve beyond this point risks stripping the valve seat, causing a hydraulic leak that requires full cylinder replacement. Make adjustments in 1/8-turn increments and test after each adjustment.

Cover Plate (4040XP-72 and 4040XP-72-MC)

The 4040XP ships with a snap-fit non-handed plastic cover (part 4040XP-72) that protects the cylinder body and presents a clean finished appearance. The metal cover (part 4040XP-72-MC) is an optional upgrade for applications where the plastic cover is subject to physical abuse or where a more durable appearance is required. The snap-fit retention design on the current 4040XP cover is an improvement over earlier designs that required fasteners at each end.

Drop Plates and Mounting Brackets

Drop plates offset the closer body from the standard mounting position to accommodate non-standard door frame geometry, flush ceiling conditions, or narrow top rails that prevent direct mounting. LCN produces several drop plate configurations for the 4040XP. The 4040XP-18PA is the parallel arm drop plate. The 4040XP-18TJ is the top jamb push-side drop plate, which permits 120-degree maximum opening. Specifying the wrong drop plate or omitting one that is actually required causes arm binding, uneven door travel, and accelerated wear on the spindle.

Spindle and Bearing Assembly

The spindle connects the arm to the pinion shaft inside the cylinder body. The 4040XP uses full complement low-friction bearings to distribute load evenly across the full bearing race. Spindle wear produces a loose, rattling arm with noticeable play when the door is opened manually. Continuing to operate a closer with a worn spindle puts progressively increasing side load on the cylinder body, which accelerates wear and can eventually damage the housing threads. Spindle replacement is available without replacing the full cylinder assembly.

LCN Concealed Closers: 2030, 3030 and 3130 Series Parts

Concealed closers are specified when surface hardware is architecturally unacceptable. The body mounts inside the door frame transom or within the door top rail, making the hardware invisible when the door is closed. These are the closers found in hotel lobbies, high-end office building entrances, healthcare reception areas, and government buildings where the aesthetic standard prohibits visible surface hardware.

LCN 2030 / 5030 / 6030 Series

The 2030 Series is LCN's heavy-duty concealed closer for high-traffic applications. The body conceals in the frame transom and the arm track conceals in the door top rail, making all hardware invisible from both sides of the door. The 5010 variant conceals only the body in the frame while using an exposed double-lever arm. The 6030 is sized for heavy doors in demanding institutional environments. Parts include the track assembly, track roller, cylinder assembly, and mounting package. Track rollers on the 2030 series are among the most frequently replaced components because they take direct mechanical contact on every door cycle.

LCN 3030 / 3130 Series

The 3030 uses an exposed double-lever arm with the body concealed in the frame transom. The 3130 adds a concealed single-lever arm with a low-friction track and roller assembly, minimizing visible hardware even further. Both carry ANSI/BHMA A156.4 Grade 1 ratings. Parts for the 3130 include the track roller assembly (part 3130-3034H), cylinder assembly, and arm components. The track roller on the 3130 is a wear item on high-traffic doors and should be inspected during annual fire door maintenance.

LCN Sentronic Electromagnetic Hold-Open Closers

The 3130SE, 4040SE, 4310ME, and 4410ME Sentronic series integrate an electromagnetic hold-open coil that connects to the building's fire alarm system. During normal operation, the electromagnetic coil holds the door open. When the fire alarm activates, power is interrupted, the coil releases, and the spring drives the door closed. This is the correct specification under NFPA 80 Section 6.6.1 for fire and smoke barrier doors that must remain open during occupied hours but close automatically on alarm activation. Parts include the magnet assembly (SEM 7800 Series), coil components, and the closer cylinder assembly specific to each Sentronic model.

Parts That Fail First on LCN Closers: A Realistic Ranking

After 30-plus years of supplying commercial door hardware parts, we know the actual failure sequence. Here is what breaks, in the order it breaks.

1. Hydraulic cylinder seals: The most common LCN failure in the field. Oil visible on the door frame or floor confirms seal failure. The cylinder must be replaced as a unit. No field repair. No refill. Order the replacement cylinder matched to your model number and finish.

2. Arm assembly: Arms crack, bend, or strip their spindle connection on high-abuse applications. A bent arm causes uneven door travel and rapidly accelerates spindle wear in the cylinder body. Replace the arm before the cylinder sustains secondary damage. Always match the arm suffix to the exact model on the closer body.

3. Spring tension loss: After 10 or more years of continuous use in high-traffic locations, the coil spring loses tension and the door fails to latch consistently. The Green Dial can compensate for minor tension loss, but cannot overcome a spring that has lost its mechanical memory. Cylinder replacement is the correct resolution.

4. Spindle and bearing wear: Produces noticeable arm play and a loose, rattling door. Most common in correctional, healthcare, and educational environments where doors are opened hard repeatedly. Replace before the side loading damages the cylinder body threads.

5. Cover plate damage: Cracks or breaks from deliberate abuse or cart impact on corridor doors. The plastic cover (4040XP-72) is available individually. In high-abuse settings, upgrade to the metal cover (4040XP-72-MC) on replacement.

6. Drop plate and shoe fastener failure: Loose mounting screws cause arm play that looks like spindle wear. Check and tighten all mounting fasteners before ordering spindle components.

How to Identify Your LCN Closer Model Before Ordering Parts

The model number is the only reliable identifier for ordering LCN replacement parts. Physical appearance is not sufficient because multiple LCN series look nearly identical from the outside but use different internal components, different arms, and different mounting hardware.

Remove the cover plate (two fasteners at the ends of the cover on most models). The model and finish code are on a sticker attached to the cylinder body. The model number format is typically: series designation, suffix code, and finish code. For example, 4040XP-3077-689 identifies a 4040XP series with a standard regular arm and aluminum finish.

For older units where the sticker has worn off, measure the horizontal center-to-center hole distance on the closer body. LCN body sizes are standardized across production runs, and those dimensions can narrow the identification to a small number of candidates. If the body casting shows numbers like "71" or "320G," those are internal casting marks, not model numbers. They identify the production run, not the series. Always use the sticker model number for parts ordering.

What nobody else tells you: The 4040XP directly replaces and retrofits the older 4041 closer. All 4041 accessories are compatible with the 4040XP body. If you have an older 4041 body that needs arm replacement, current 4040XP arms and accessories will fit. This eliminates the need to carry legacy 4041 inventory for facilities with older installations.

LCN Door Closer Adjustment: Step-by-Step

Proper adjustment prevents the most common LCN service calls and extends cylinder life. Follow this sequence for any new installation or post-repair adjustment.

Step 1: Set All Valves to a Known Baseline

Turn all adjustment valves clockwise until they seat gently. Do not overtighten. The valve seats are brass and will strip. From fully closed, open each valve 1.5 turns counterclockwise. This is the approximate factory starting position.

Step 2: Set Spring Power with the Green Dial

Use LCN's sizing chart to determine the correct spring size for the door width, door weight, and mounting configuration. Set the Green Dial to that position. For parallel arm mounting, add one size. Check the actual opening force with a calibrated force gauge if ADA compliance is required. 5 pounds maximum is the ADA threshold for interior non-fire-rated doors.

Step 3: Set Sweep Speed

Open the door to 90 degrees and time the closing arc from 90 degrees to within 3 inches of the latch. ADA requires a minimum of 5 seconds. Adjust the sweep valve in 1/8-turn increments until the timing is correct. Test at least three consecutive closes to confirm consistency.

Step 4: Set Latch Speed

Watch the final 10 to 15 degrees before the door closes. The latch should engage cleanly with a firm click, not a slam. If the door stops short of latching, open the latch valve slightly. If it slams in the final arc, close the latch valve slightly. On fire-rated doors, positive latching on every close is a NFPA 80 compliance requirement, not a preference.

Step 5: Set Backcheck

Open the door quickly past 70 degrees and feel for resistance. Backcheck should provide a cushioning effect that prevents the door from slamming into a wall, but should not prevent full opening. If backcheck engages before 70 degrees and restricts normal door use, open the backcheck valve slightly. If there is no backcheck at all and the door swings freely to 180 degrees, close the backcheck valve clockwise until resistance is felt at 70 to 75 degrees of opening.

Never unscrew any LCN valve more than 1.5 turns from fully closed. Opening a valve beyond 1.5 turns risks hydraulic fluid leaking from the valve bore. A leaking cylinder cannot be refilled. Replacing it costs far more than the few seconds saved by skipping this limit.

LCN Sentronic and Fire Door Applications

LCN Sentronic electromagnetic hold-open closers are the correct specification for any fire or smoke barrier door that must remain open during normal building operations. They are not optional convenience items. NFPA 80 Section 6.6.1 specifies that a fire door held open by any device must be connected to the building fire alarm system so it closes automatically on alarm activation.

Using a mechanical wedge, a rubber doorstop, or any manual hold-open device on a fire-rated door is a NFPA 80 violation that creates both a code compliance issue and a liability exposure. The Sentronic series eliminates this problem by integrating the hold-open function into a UL-listed fire door hardware assembly that responds automatically to the fire alarm system.

Parts for Sentronic series closers include the SEM 7800 Series magnet assemblies, the electromagnetic coil components, and the closer cylinder assembly. Browse the full door closers parts catalog for all Sentronic series diagrams and components.

Why Choose SecurityParts.com for LCN Door Closer Parts

We stock the full LCN catalog with interactive exploded diagrams so you confirm the right component visually before ordering.

Interactive Diagram Lookup

Every LCN model page has an exploded diagram. Click the component, confirm it, add to cart. No guessing from part descriptions alone.

Individual Parts Stocked

One arm, one cover plate, one drop plate. No minimum quantities and no forced kit purchases to get a single replacement component.

Same-Day Shipping

Most LCN parts ship same day from US warehouses. A door out of service on a code-required fire door path is not a situation that waits a week.

Pre-Order Support

Call 845-935-0301 or use the contact page. We confirm the correct part from your model number before the order ships.

What Makes SecurityParts.com Different for LCN Parts

We stock LCN parts organized by series with separate model pages. The 4040XP, 3030, 3130, 2030, and Sentronic series are each cataloged individually so the correct component is identifiable without guesswork.
We document the 4041-to-4040XP retrofit compatibility. If you have an older 4041 body, current 4040XP accessories fit. You do not need to find discontinued 4041 inventory.
We explain the parallel arm sizing adjustment that most suppliers omit. Add one full spring size when using parallel arm mounting. This one field fact prevents the most common post-installation latch failure.
We carry LCN alongside Von Duprin exit device parts, electric strike parts, and cylindrical lock parts. One order covers a complete institutional door service call.
Same-day shipping from US warehouses. Free shipping on orders over $450, which most facility service call orders reach.
30-plus years of commercial hardware experience. When you describe the symptom, we identify the part, not just the series.

Related Parts and Products at SecurityParts.com

LCN door closers are part of a complete door hardware assembly. A full service call on an institutional door typically involves the closer, the exit device, and sometimes an electric strike or lock hardware on the same opening.

For Von Duprin and Falcon exit device parts on the same door, browse the commercial exit devices catalog by brand and series. For Von Duprin electric strike parts including 5100, 6100, 6200, and 6300 series, browse the electric strikes catalog. For mortise lock parts on high-security doors in the same facility, browse the mortise locks catalog. For Von Duprin Guard-X exit alarm parts on secondary exits, browse the exit alarms catalog. For Schlage and Falcon cylindrical lock parts on interior office and corridor doors, browse the cylindrical locks catalog.

Browse the complete all products and parts catalog to source Von Duprin, LCN, Schlage, Falcon, and Detex in a single session, or reach the team at 845-935-0301 for pre-order compatibility support.

Frequently Asked Questions About LCN Door Closer Parts

What LCN door closer series does SecurityParts.com carry parts for?

SecurityParts.com carries replacement parts and diagrams for the LCN 1000 Series, 2210 Series, 2310ME/4310ME/4410ME Sentronic, 2610/4810/4820/4840 Auto Equalizer Operators, 3130SE/4040SE Sentronic, 4000 Series surface closers, 4040SEH Holder, 4210/4510 Smoothee, 4310HSA/4410HSA Sentronic, 4630/4640 Auto Equalizer Operators, 9130/9140/9150 Benchmark Operators, 9500/2800 Senior Swing Operator, Sentronic SEM 7800 Series Magnets, 2010/5010, 2030/5030/6030, and 3030/3130 concealed closers.

What is the LCN Green Dial and how do I use it?

The Green Dial is a patented visual indicator on the 4040XP spring tube showing the current spring power setting from size 1 through 6. The closer ships set to size 3. Turn the 5/32-inch hex screw clockwise to increase spring power. For parallel arm mounting, add one full spring size to any sizing chart recommendation. After any spring adjustment, verify actual opening force with a calibrated force gauge for ADA compliance.

What hydraulic fluid does the LCN 4040XP use?

The 4040XP uses Liquid X all-weather hydraulic fluid, which operates from -30 degrees F to 120 degrees F in manual closer applications. LCN closers are not designed for field fluid refills. A leaking cylinder must be replaced as a complete assembly. Attempting to add fluid to a leaking closer body does not restore function.

Are LCN door closer arms interchangeable between series?

No. Arms are model-specific. A 4040 series arm does not fit a 4011 body even though the bodies look similar. Always match the arm part number to the exact model number stamped on the closer body. Using an incompatible arm causes improper door geometry and accelerates spindle wear.

Why does my LCN door closer still slam after I adjust the sweep valve?

If the sweep valve is fully open and the door still slams, hydraulic fluid has leaked from the cylinder. Without fluid, the closer becomes a raw spring with no damping. No valve adjustment fixes this. Replace the cylinder assembly. Oil visible on the door frame or floor confirms the diagnosis.

What is the difference between the LCN 4040XP and the LCN 4000 Series?

The 4040XP is the current production heavy-duty closer in the 4000 Series family. It features an enlarged 3/4-inch pinion shaft with 44 percent greater bearing load capacity than the original 4040, Liquid X all-weather fluid, Green Dial spring indicator, patent-pending snap-fit cover, and labeled regulation valves. The 4040XP directly replaces and retrofits the older 4041. All 4041 accessories are compatible with the 4040XP body.

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Von Duprin 98/99 Series Exit Device: Complete Parts and Service Guide Tuesday, June 16, 2026

The Von Duprin 98/99 series is on more institutional doors than any other exit device in North America. Schools, hospitals, government buildings, universities, airports. If you manage a commercial facility or work as a locksmith, you will service this device more than any other in the Von Duprin lineup.

This guide covers everything you need to work on 98/99 series exit device parts efficiently. It covers the configurations, the parts that fail, the dogging details that trip people up, the electrified options, and exactly how to order the right component without a return. Browse the full Von Duprin parts catalog at SecurityParts.com for model-specific diagrams on every series.

What Makes the 98/99 Series Different From Other Von Duprin Devices

The 98/99 sits at the top of the Von Duprin lineup. It is the deepest specification in terms of electrified options, the most configurable in terms of device type, and the only Von Duprin series that carries full Made in USA production. ANSI/BHMA A156.3 Grade 1 certification means it is tested to the highest cycle and force standards in the exit device category.

The case distinction is simple: the 98 series has a smooth mechanism case and the 99 series has a grooved case. Both are mechanically identical. The grooved case on the 99 gives a better grip surface under repeated push pad contact, which is why healthcare and institutional specifications often call for the 99 specifically.

The forward compatibility advantage is what separates the 98/99 from every other series. A mechanical device installed today can be converted to QEL quiet electric latch retraction, MEL motorized retraction, Chexit delayed egress, Allegion Connect, or other access control options years later without replacing the device body. Facilities managers doing phased access control upgrades depend on this.

98/99 Series Configurations: Which One Fits Your Door

Rim Device (98, 99, F-98, F-99)

The rim device mounts on the door face and latches at a single frame-side strike. Standard for single doors and paired doors with a center mullion. The F-prefix versions (F-98, F-99) are fire exit hardware with a UL fire listing. They must positively latch on every door close and do not support hex dogging. The standard 98/99 (without F-prefix) is panic exit hardware that supports mechanical dogging on non-fire-rated doors.

Surface Vertical Rod (9827, 9927)

SVR devices add top and bottom engagement rods running on the door face, providing three-point locking for double door openings without a center mullion. The 9827 is the 98 series SVR and the 9927 is the 99 series SVR. Both use a dedicated center case (part 109358) which is different from the rim device center case (part 109012). These are not interchangeable. Confirm configuration before ordering any center case.

Concealed Vertical Rod (9847, 9947)

CVR devices route the rod hardware inside the door for architectural applications where surface rods are not acceptable. Hotel lobbies, healthcare reception areas, high-end commercial interiors. CVR parts must match the exact model and door prep. CVR installation is typically done at the factory; field replacement of internal rod components requires door removal in most cases.

Wide Door Cable (WDC)

The WDC configuration uses a cable rather than rigid rods for very wide double doors where rod flex would be a problem. Available on the 98/99 series for oversized openings.

Mortise Device (98/9975, XP98/XP99)

The mortise configuration integrates the 7500 mortise lock body into the panic device chassis for maximum security depth alongside code-compliant egress. The 7500 mortise lock body has been in service since approximately 1977. Browse mortise lock replacement parts for the 7500 body components that pair with the 98/9975 mortise exit device.

Configuration	Model Numbers	Door Type	Center Case Part
Rim (panic)	98, 99	Single door, mullion pair	109012
Rim (fire)	F-98, F-99	Fire-rated, single door	109012
SVR (panic)	9827, 9927	Double door, no mullion	109358
SVR (fire)	F-9827, F-9927	Fire-rated double door	109358
CVR	9847, 9947	Architectural double door	Model-specific
Mortise	9875, 9975	High-security single door	Model-specific

Panic vs Fire Exit Hardware on the 98/99 Series

Every 98/99 series device is available in both standard panic and fire exit hardware versions. Getting this wrong before ordering replacement parts is the most common mistake in 98/99 series maintenance.

Standard panic devices (98, 99, 9827, 9927): UL listed for panic exit applications. Support mechanical hex dogging. Channel cover plates specific to panic configuration.

Fire exit hardware (F-98, F-99, F-9827, F-9927): UL listed for fire exit hardware. The F-prefix in the model number confirms this. Must positively latch on every door close. Hex dogging is not permitted. Channel cover plates carry different part numbers from the panic versions.

Critical: Installing a panic channel cover plate on an F-series device voids the UL fire exit hardware listing. Always check whether the device is fire-rated before ordering any cover plate replacement.

Dogging on the 98/99 Series

Hex dogging holds the push pad depressed during business hours so the door operates as a push/pull entry without latching. Standard on all panic-rated 98/99 devices. Not available on F-series fire exit hardware.

Why Dogging Fails on the 98/99

The dogging shaft hole (part 090040) is approximately 1/4 inch deep. The most common cause of dogging failure in the field is using a short 5/32-inch hex key that does not reach full depth. Short keys round out the hex engagement point over repeated use, requiring shaft replacement. Always use the long version of the 5/32-inch hex key and seat it fully before rotating.

The dogging assembly has three components:

090040 Dogging Shaft: The piece the hex key engages. Field note: the pre-1998 shaft has a different profile. For devices manufactured before 1998, use part 050709 conversion kit.

090042 Dogging Adapter Spring: Locks the adapter into the mounting bracket.

090043 Dogging Adapter: The housing the shaft and spring fit through.

Field tip: If dogging worked previously but now the hex key spins without engaging, the shaft is stripped. Order part 090040 and replace it before the surrounding housing sustains damage.

Parts That Fail First on the 98/99 Series

Based on actual field replacement frequency, here is a realistic sequence of what wears out first:

1. Dogging assembly: The most common maintenance item on high-traffic doors. Shaft strips, springs fatigue, adapters crack. All three components are available individually.

2. End cap and bracket: The plastic end cap on the hinge side of the device breaks under repeated contact. When it breaks, the dogging cover plate slides off. Von Duprin introduced the 900397 metal end cap kit in 2016 to replace the historically fragile plastic version. This is a worthwhile proactive upgrade on any high-use 98/99 device.

3. Push bar retrofit kit: The push bar assembly bends or deforms on high-abuse applications. Push bar retrofit kits are available for 3-foot and 4-foot door widths, replacing just the push bar without requiring a full device swap.

4. Center case: The center case (109012 for rim, 109358 for SVR) wears after decades of continuous use. The 109012 rim center case has been in production for approximately 40 years and replaces all non-fire-rated 98/99 rim center cases with backward compatibility to devices installed in the 1980s. This long backward compatibility chain is one of the most valuable maintenance advantages of the 98/99 series.

5. Latch return spring (090039): Used in the push bar assembly to return the latch. Fails from spring fatigue on very high-cycle doors.

Electrified Options on the 98/99 Series

The 98/99 series has the deepest electrified options catalog of any Von Duprin device. Each option converts or adds to the mechanical device without replacing the body.

QEL: Quiet Electric Latch Retraction

The QEL is a modular field-installable kit that adds electric latch retraction to a mechanical 98/99 device. When an authorized credential is presented, the latch retracts silently. This is the most commonly specified electrified conversion on existing 98/99 devices in phased access control upgrades. The HD-QEL variant adds hex dogging capability to the electrified device.

MEL: Motorized Electric Latch Retraction

Motor-driven latch retraction for applications where solenoid noise is not acceptable. Quieter operation than standard EL. Used in library environments, healthcare patient areas, and quiet office zones.

Chexit: Delayed Egress

Holds the door latched for 15 seconds after the push bar is activated, with a local alarm sounding during the delay. NFPA 101 compliant for controlled egress applications. Used in retail, psychiatric facilities, and any location where unauthorized egress must be deterred without blocking emergency egress.

RX: Request to Exit

A switch placed in the push bar that signals the access control panel when the bar is pressed. Notifies the system of an authorized egress event to prevent false alarms on the secured entry side. Standard on any 98/99 device integrated into an access control system where the door also serves as a secured entry. The electric strikes parts catalog covers the Von Duprin electric strikes on the frame side that work alongside RX-equipped exit devices.

LX: Latch Bolt Monitoring

Monitors the position of the latch bolt, signaling the access panel when the door is not properly latched. Used on fire doors and secured doors where latch compliance monitoring is required by the inspection program.

ALK: Alarm Exit Kit

Converts the 98/99 to an alarmed exit device. Powered by a 9-volt battery. Controlled by a mortise cylinder (not included). When the push bar is pressed, the 85-decibel alarm sounds. The ALK is shared across the 22, 33A, 35A, 98, and 99 series.

CON: Allegion Connect

Wireless integration into the Allegion Connect ecosystem for remote monitoring and control.

How to Order 98/99 Series Parts Without a Wrong-Part Return

Three pieces of information are required before placing any 98/99 series parts order.

1. Confirm the configuration: Rim or SVR changes the center case part number entirely (109012 vs 109358). CVR and mortise use model-specific parts. Confirm which configuration is on the door before opening any catalog page.

2. Check the manufacture date: The manufacture date is stamped near the mechanism housing on the device body. Devices manufactured before 1998 use old-style dogging assemblies. The conversion kit (part 050709) updates pre-1998 devices to current spec dogging components. Post-1998 devices use parts 090040, 090042, and 090043.

3. Confirm panic or fire exit hardware: The F-prefix in the model number confirms fire exit hardware. Channel cover plates, dogging kits, and some trim components carry different part numbers between panic and fire configurations. Never order channel cover plates without confirming first.

SecurityParts.com organizes the complete Von Duprin 98/99 series parts catalog by model with interactive exploded diagrams on every model page. You confirm the component visually before ordering. Pre-order compatibility support is available at 845-935-0301 or through the contact page.

Why Choose SecurityParts.com for Von Duprin 98/99 Parts

Diagram-Based Identification

Every 98/99 model page has an interactive exploded diagram. You see exactly where each part sits before adding it to your cart.

Parts-Level Stocking

Individual components stocked: one dogging shaft, one end cap kit, one push bar retrofit kit. No forced kit purchases for a single replacement part.

Same-Day Shipping

Most 98/99 components ship same day from US warehouses. An exit device out of service on an egress door is a safety and compliance issue.

Pre-Order Support

Call 845-935-0301 or use the contact page. Our team confirms part compatibility from your manufacture date and configuration before the order ships.

What Makes SecurityParts.com Different

We stock Von Duprin parts by series and configuration, not by generic brand listing. Rim and SVR center cases are listed separately so you order the right one the first time.
Backward compatibility is documented. We note which parts apply to pre-1998 devices versus current production, so you don't order a current-spec dogging shaft for a device that needs the 050709 conversion kit.
Individual components are available. One dogging shaft, one latch return spring, one end cap kit. No minimum quantities, no forced kit purchases.
We carry Von Duprin alongside LCN door closers, Falcon exit devices, and cylindrical lock parts. One order covers a complete facility service call across multiple brands.
Same-day shipping on stocked parts. Free shipping on orders over $450.
30-plus years of commercial door hardware experience. We diagnose based on symptoms, not just catalog lookups.

Related Parts at SecurityParts.com

The 98/99 series operates as part of a complete door assembly. A full service call on an institutional door typically covers the exit device, the door closer, and sometimes an electric strike or lock hardware on the same opening.

For LCN door closer parts on the same opening, browse the door closers catalog by series. For Von Duprin electric strike parts, including 5100, 6100, 6200, and 6300 series, used on the frame side alongside 98/99 exit devices, browse the electric strikes catalog. For Von Duprin Guard-X exit alarm parts on secondary exits in the same building, browse the exit alarms catalog. For Schlage deadbolt parts on interior office doors in the same facility, browse the deadbolts catalog.

Browse all Von Duprin series: 22, 33A, 75, 88, 94/95, and the Guard-X, in the Von Duprin parts catalog, or explore the full commercial exit devices parts catalog to navigate by brand and series.

Frequently Asked Questions

What is the Von Duprin 98/99 series exit device?

The Von Duprin 98/99 is the institutional flagship exit device made by Allegion. ANSI/BHMA Grade 1 certified and UL listed for panic and fire exit hardware. Made in the USA. Available in rim, SVR, CVR, WDC, and mortise configurations with the deepest electrified options catalog in the Von Duprin lineup.

What is the difference between the Von Duprin 98 and 99 series?

The 98 has a smooth mechanism case and the 99 has a grooved case. Both are mechanically identical inside and use the same replacement parts. The grooved case on the 99 provides a better grip surface for high-contact institutional applications.

What is the dogging hole depth on the Von Duprin 98/99 series?

The dogging shaft hole is approximately 1/4 inch deep. Always use a long 5/32-inch hex key and seat it completely before rotating. Short hex keys strip the engagement point over time, which is the most common cause of dogging failure on 98/99 devices in the field.

Can I upgrade a mechanical 98/99 to electric latch retraction later?

Yes. This is the key forward compatibility advantage. A mechanical 98/99 can be field-converted to QEL, MEL, Chexit, or Allegion Connect years later without replacing the device body. This is why architects default to the 98/99 on institutional projects where phased access control is planned.

Are 98 series and 99 series parts interchangeable?

Yes. The 98 and 99 series use identical internal parts. The only difference is the exterior case finish. Any push bar, latch assembly, dogging component, center case, or electrified kit ordered for the 98 fits the 99 of the same configuration and manufacture date.

What is the Von Duprin 9927 and how does it differ from the 99 rim device?

The 9927 is the surface vertical rod (SVR) configuration of the 99 series. It uses top and bottom engagement rods for three-point locking on double doors without a center mullion. The rim device uses center case 109012. The 9927 uses center case 109358. These are completely different parts. Confirm configuration before ordering any center case.

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Mortise Locks vs Cylindrical Locks: Which One Does Your Door Need? Sunday, June 14, 2026

If you're buying door hardware for a commercial project, you'll run into this choice pretty quickly: mortise lock or cylindrical lock? They both secure a door. They both come in Grade 1. But they work differently, install differently, and belong on different types of openings.

Here's a plain-language breakdown so you can pick the right one without overthinking it.

What Is a Mortise Lock

A mortise lock lives inside the door. To install one, a rectangular pocket (the mortise) has to be cut into the door edge. The lock body, which is a self-contained steel case, drops into that pocket and houses the latch bolt, deadbolt, and internal mechanism all in one unit. The lever or knob trim attaches through the door face with through-bolts that run the full thickness of the door.

That deep, integrated installation is what makes mortise locks strong. The mechanism is anchored inside the door structure itself, not just surface-mounted. The result is a lock that resists forced entry, handles heavy daily use, and offers more function options like entry, classroom, storeroom, and office functions, all within the same lock body.

You'll find mortise locks on the primary entrances of hotels, office buildings, schools, and government facilities. Any commercial door that sees constant traffic and needs serious security is a candidate for a mortise lock.

What Is a Cylindrical Lock

A cylindrical lock installs through two round bored holes drilled into the door: a larger hole through the face and a smaller one through the edge for the latch. The lock chassis sits in the face bore, and the latch mechanism sits in the edge bore. Lever or knob trim threads onto each side.

It's a simpler system. Installation is faster, the hardware costs less, and most doors in commercial buildings already come pre-drilled for cylindrical preps. That's why cylindrical locks are the most common lock type overall. They're practical, widely available, and perfectly adequate for a huge range of applications.

Most interior commercial doors use cylindrical locksets: office rooms, storage closets, conference rooms, restroom corridors. Grade 1 cylindrical locks from brands like Schlage, Sargent, or Yale handle this kind of use comfortably for years.

The Key Differences Side by Side

Installation

Cylindrical locks install in minutes on a pre-drilled door. Mortise locks require a precisely cut pocket in the door edge, and it's a more involved process and typically needs to be done by a professional or specified at the time the door is manufactured. Once the door prep exists, swapping hardware is straightforward. But you can't put a mortise lock on a door drilled for cylindrical hardware, or vice versa. The two preps are incompatible with no field workaround.

Security and Strength

Both types come in ANSI/BHMA Grade 1, which is the commercial standard. But a Grade 1 mortise lock and a Grade 1 cylindrical lock aren't structurally identical. The mortise lock's integrated case gives it an inherently stronger platform. The latch, bolt, and springs all live in one reinforced unit anchored deep in the door. A cylindrical lock relies more on the door's structural integrity around the bore holes. For primary entries and high-security applications, mortise wins. For standard interior commercial doors, a Grade 1 cylindrical lock is more than sufficient.

Functions Available

Mortise locks offer a wider range of functions in one unit, including entry, classroom, storeroom, hotel, and apartment functions, without needing separate hardware. Cylindrical locks also cover these functions but sometimes require adding a separate deadbolt to match the security level of a mortise set. Mortise locks also offer significantly more trim design options, which matters in architectural or high-end commercial projects where appearance is part of the specification.

Cost

Cylindrical locks are less expensive. Good Grade 1 commercial cylindrical hardware runs roughly $150 to $350 per opening. Grade 1 mortise locksets start around $300 and can go well past $600 per opening, not including professional installation labor for new door prep. On a building with 150 doors, that cost difference is significant. The right answer is using mortise where it's genuinely needed and cylindrical everywhere else, not defaulting to one type for the whole project.

Long-Term Durability

In heavy-use commercial environments, mortise locks tend to last longer. Their integrated design distributes stress across a larger case, which holds up better under constant door cycling. Cylindrical locks work well in their right applications but can wear out faster on a primary entry that processes hundreds of people a day. Mortise locks hold about 40% of the commercial door hardware market, favored for their durability in demanding environments, while cylindrical locks account for the remaining 60%, chosen for cost-effectiveness and straightforward installation.

Which One Should You Choose

The honest answer is: it depends on what the door is doing.

Use a mortise lock when: the door is a primary exterior entry, a high-traffic corridor in a school or healthcare facility, a hotel room entry, or any opening where security and long-term durability are the top priorities. Also use mortise when the door is already prepped for it. There's no reason to modify a door that's built for mortise hardware.

Use a cylindrical lock when: the door is an interior office, storage room, conference room, or any lower-traffic opening where a Grade 1 cylindrical lockset covers the security requirement. Most interior commercial doors fall into this category. Cylindrical is also the practical choice when budget is a real constraint on a multi-door project.

Never mix preps on the same door. If a door was manufactured with a cylindrical prep (ANSI 161), it needs cylindrical hardware. If it has a mortise prep (ANSI 86), it needs a mortise lock. Ordering the wrong one means returning it and waiting for the right hardware, a mistake that's easy to avoid by confirming the door prep before you order.

What About ANSI Grades

For any commercial door, Grade 1 is the right starting point. Both mortise and cylindrical locks are available in Grade 1 under ANSI/BHMA standards. A156.13 covers mortise locks and A156.2 covers cylindrical locks. Grade 1 cylindrical locks are tested to 800,000 cycles. Grade 1 mortise locks are held to similar cycle requirements with additional strength testing for the bolt and case.

Grade 2 is acceptable for interior commercial doors with light use. Grade 3 is residential hardware and shouldn't appear on a commercial specification. If you see a lock listed without a grade, skip it. The absence of certification is a red flag regardless of what the marketing says.

Top Brands to Know

For mortise locks, the names you'll see on most commercial specifications are Schlage (L-Series), Sargent (7000 Series), Corbin Russwin (ML2000 Series), and Yale (8800 Series). These are the brands architects and facility managers specify by name on door hardware schedules.

For cylindrical locks, Schlage (AL and ND Series), Sargent (10 Line), Best (9K Series), and Cal-Royal are the dominant commercial options. All manufacture Grade 1 products with interchangeable core options for large facilities that need master key systems.

Shop Door Locks at SecurityParts.com

SecurityParts.com carries both mortise and cylindrical locksets from the brands contractors and facility managers rely on. Every product listing includes the manufacturer's spec sheet so you can confirm the ANSI grade, function, and door prep before ordering.

Whether you're sourcing hardware for a full door schedule or replacing a single lockset, browse our mortise locks and cylindrical locks to find the right fit for your opening.

Frequently Asked Questions

What is the difference between a mortise lock and a cylindrical lock?

A mortise lock installs inside a rectangular pocket in the door edge and houses the latch, deadbolt, and mechanism in one steel case. A cylindrical lock installs through two round bored holes in the door and is a simpler, more compact system. Mortise locks are stronger and offer more functions. Cylindrical locks are faster to install and more affordable.

Which is better for commercial doors: mortise or cylindrical?

Mortise locks are the standard for primary commercial entries and high-traffic openings. Cylindrical locks are widely used on interior commercial doors like offices and storage rooms where security demands are more moderate. Both are correct answers, just for different doors.

Can I replace a mortise lock with a cylindrical lock?

No. The door preps are incompatible. A mortise lock needs a rectangular pocket in the door edge. A cylindrical lock needs two round bored holes. There's no field modification that bridges them. You need hardware that matches the prep the door was built with.

How much does a commercial mortise lock cost compared to a cylindrical lock?

Grade 1 cylindrical hardware typically runs $150 to $350 per opening. Grade 1 mortise locksets generally start around $300 and can exceed $600, not including professional labor for new mortise prep work. Cylindrical costs less upfront. Mortise tends to offer better long-term value on heavy-use commercial doors.

What ANSI grade should a commercial door lock be?

Grade 1 for exterior, high-traffic, and fire-rated commercial doors. Grade 2 is acceptable for low-traffic interior doors. Grade 3 is residential only and shouldn't appear on any commercial specification.

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Falcon 19, 24 and 25 Series Exit Device Parts: Complete Replacement Guide Friday, June 12, 2026

Grade 1 ANSI/BHMA A156.3 certification on all three Falcon series

108004 Shared service manual number for 24 and 25 Series

June 2012 HWEA alarm assembly redesign date affecting board compatibility

24V DC EL solenoid voltage, 0.34A continuous duty on 24 and 25 Series

Falcon 19 vs 24 vs 25 Series: Which One Is Installed

Falcon 19 Series

Narrow Stile | Light-to-Medium Duty

Falcon 24 Series

Narrow Stile | Heavy Duty | Aluminum Storefronts

Falcon 25 Series

Wide Stile | Heavy Duty | Hollow Metal and Wood

What Exit Device Configurations Mean for Parts Ordering

Each series offers multiple configurations that determine which latch hardware, rods, and strikes are involved. The configuration suffix on the model number tells you what is installed.

Suffix	Configuration	Latching	Application
-R	Rim exit device	Single-point, rim latch at device head	Standard single doors, paired doors with mullion
-V	Surface vertical rod	Two-point: top latch at device head, bottom rod to floor	Single doors, double doors without mullion
-C	Concealed vertical rod	Two-point: rods run inside door stile	Doors requiring clean exterior face with no exposed hardware
-CWDC	Wide door cable/concealed, wood door	Two-point concealed for wood door construction	Wide or wood doors requiring concealed rod hardware
-M	Mortise exit device	Mortise lock case inside door, device operates latch	Heavy-duty perimeter doors requiring mortise body strength; 25 Series only
F- prefix	Fire-rated version	Same as panic version but fire-listed	Any fire-rated door assembly; cannot be dogged

Why the Rim vs Vertical Rod Distinction Matters for Parts

Falcon 19 Series Parts: Channels, End Caps and Key Components

Part Number	Description	Notes
4107	19 Series channel, 3-foot door	Standard channel for doors up to 3 feet
4108	19 Series channel, 4-foot door	Standard channel for doors up to 4 feet
650343	19 Series channel end cap kit (with screws)	Includes end cap, bracket, and all mounting hardware
650320	19 Series end cap mounting bracket with SNB	Bracket only, for bracket replacement without full kit
4122	Sex bolt, package of 1 (includes machine screw)	Mounting fastener; #10-20 thread
650360	F-19 channel cover plate, 3-foot (fire)	Fire-rated version only, 3-foot door
650361	F-19 channel cover plate, 4-foot (fire)	Fire-rated version only, 4-foot door
650297	19 Series panic hex dogging channel cover, 4-foot	Panic (non-fire) version, 4-foot door
650303	19 Series panic hex dogging channel cover, 3-foot	Panic (non-fire) version, 3-foot door

Falcon 24 Series Parts: Heavy Duty Narrow Stile

Part Number	Description	Notes
661408	24 Series channel, 3-foot door	Extruded aluminum construction
661409	24 Series channel, 4-foot door	Extruded aluminum construction
650294	24 Series channel end cap kit, 1-3/4-inch door	Kit includes end cap, bracket, and all fasteners for standard door thickness
650348	24 Series channel end cap kit, 2-1/2-inch door	Kit for thicker than standard door applications
650147	24/25 Series EL kit, 3-foot device	Electric latch retraction for 3-foot channel devices
650148	24/25 Series EL kit, 4-foot device	Electric latch retraction for 4-foot channel devices

The 24 Series Door Thickness and End Cap Selection

Falcon 25 Series Parts: Wide Stile Heavy Duty

25 Series Dogging: Half-Turn Hex, No Threads

25 Series Configurations and Stile Requirements

25 Series Configuration	Minimum Stile	Door Type	Fire Rating
25-R (rim)	4-1/2 inch	Metal or wood	Optional B label (F-25-R)
25-V (surface VR)	4-1/2 inch	Metal or wood	Optional B label (F-25-V); A label available on fire pair
25-C (concealed VR, metal door)	3-1/2 inch (panic); 4-1/2 inch (fire)	Metal doors	Optional B label and A label on fire pair (F-25-C)
25-CWDC (concealed VR, wood door)	6-1/2 inch	Wood doors	Optional B label (F-25-CWDC)
25-M (mortise)	4-1/2 inch	Metal or wood	Optional fire rating

25 Series Fire Ratings: A Label vs B Label

Hex Dogging: How It Works and What Fails

Electrified Options on the Falcon 24 and 25 Series

EL: Electric Latch Retraction

EA and HWEA: Exit Alarm Options

KOR, LM, DM, RX: Monitoring and Override Options

How to Identify the Correct Part Before Ordering

Three pieces of information are needed before any Falcon exit device parts order.

1. Series (19, 24, or 25): Determined by the door construction and stile width as described above. The series number is typically visible on a label on the device channel or center case.

Falcon vs Von Duprin: Choosing Between the Two Exit Device Brands

Why Choose Security Parts for Falcon Exit Device Parts

Series identification guidance, dogging mechanics, EL compatibility documentation, HWEA date boundary, and same-day shipping on stocked parts.

Series Identification

EL Compatibility Rules

We document that EL is unavailable on 24 Series fire rim devices and that EL and EA cannot be combined on any device. These restrictions prevent specification errors before the order is placed.

HWEA Date Boundary

We document the June 2012 alarm board redesign and that part 650335 applies only to pre-June 2012 assemblies. Using the wrong board generation installs a non-functional alarm.

Same-Day Shipping

Most Falcon 19, 24, and 25 Series parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for pre-order compatibility support.

What Makes SecurityParts.com Different for Falcon Exit Device Parts

We document the 24 Series EL restriction on fire rim devices (F-24-R) at the part level. Facility managers upgrading access control on fire-door openings routinely order EL kits for fire rim devices without knowing the restriction. We prevent this before the order ships.
We document the EL/EA mutual exclusivity. Any specification combining both on one device requires a redesign. This is in the service manual but no parts supplier makes it accessible at the ordering stage.
We document the HWEA 650335 board date boundary with the June 2012 cutoff. This is the most common wrong-board order on alarm-equipped Falcon exit devices.
We document the half-turn hex dogging failure misdiagnosis: a push bar that returns after dogging is almost always incomplete dogging technique, not a mechanism failure. This prevents unnecessary mechanism replacements on dogging complaints.
We carry Falcon exit device parts alongside Von Duprin exit device parts, electric strike parts, LCN door closer parts, and exit alarm parts. One order services the complete egress door hardware package.
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Frequently Asked Questions About Falcon 19, 24 and 25 Series Exit Device Parts

What is the difference between the Falcon 19, 24 and 25 Series exit devices?

What is dogging on an exit device and how does hex dogging work?

What are the part numbers for the Falcon 19 Series channel and end cap?

What are the part numbers for the Falcon 24 Series channel and end cap?

What is the Falcon HWEA circuit board part number and when does it apply?

What electrified options are available on the Falcon 24 and 25 Series?

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Mortise Locks: A Complete Guide to Commercial Lock Functions, Brands, and Specification Friday, June 12, 2026

Commercial mortise locks are heavy-duty locks installed inside a rectangular pocket cut into the edge of the door, with a self-contained lock body that houses the latchbolt, deadbolt, lever hub, cylinder, and internal linkages in one reinforced steel case. They're the standard for commercial buildings, hospitality, healthcare, institutional, and high-traffic facilities because they outperform cylindrical locks on durability, function variety, and security. This guide covers what mortise locks are, the ANSI function codes that define them, the major commercial brands you'll encounter, how to specify the right one, and how to source replacements without misordering.

What Is a Mortise Lock

A mortise lock is a heavy-duty lock assembly installed in a rectangular pocket (the "mortise") machined into the edge of the door itself. Unlike a cylindrical lock that passes a cylinder through two round holes bored through the door face, the mortise lock body is a self-contained mechanical assembly measuring approximately 6 inches by 4 inches by 1 inch. The case houses the latchbolt, separate deadbolt, lever hub, cylinder housing, and all internal linkages in one reinforced steel unit.

Everything load-bearing sits inside the door, not bolted to the surface. That single design choice is what makes mortise locks the dominant commercial lock category for openings that need to last twenty-plus years under heavy cycle counts.

How Mortise Locks Differ from Cylindrical Locks

The structural difference between mortise and cylindrical locks drives every other difference in performance, function, and price.

A cylindrical lock (sometimes called a bored lock) uses two cross-bored holes. The chassis passes through one, the latch crosses through the other, and trim mounts on both faces of the door. Cylindrical locks are faster to install, cheaper to manufacture, and work well on lighter-duty interior openings.

A mortise lock requires a precise pocket cut into the door edge, plus through-bores for the cylinder and lever hubs. The pocket prep takes more skilled labor at installation. In exchange, the mortise lock delivers a one-piece reinforced case, a separate 1-inch deadbolt that operates independently of the latch, and a chassis large enough to hold complex function-change mechanisms inside.

Three things mortise locks do that cylindrical locks generally can't: combine a latch and a separate deadbolt in one chassis, support classroom-security and institutional functions, and survive Grade 1 ANSI/BHMA testing on 2 million cycles.

ANSI Function Codes for Mortise Locks

The American National Standards Institute, working with the Builders Hardware Manufacturers Association, defines mortise lock behavior using F-codes. Every commercial mortise lock spec sheet references these codes. Knowing them is how you cross-reference one brand against another.

F01 Passage. Both levers always operate the latchbolt. No locking. Used on closet doors, conference rooms, interior pass-through openings.

F02 Privacy. Trim from either side retracts the latchbolt. Thumbturn inside retracts and projects a deadbolt. Emergency release from outside retracts the deadbolt. Used on bathrooms and bedrooms.

F04 Classroom. Outside lever locked or unlocked by key from outside. Inside lever always free for egress. Used on classrooms where teachers control access from the corridor.

F05 Office. Outside lever locked by toggle button inside or by key from outside. Inside lever always free. Used on offices where the occupant locks the door from inside.

F07 / F08 Storeroom. Outside lever permanently fixed. Key from outside retracts latchbolt for entry. Inside lever always free for egress. Used on IT rooms, supply rooms, mechanical rooms, electrical closets.

F13 Classroom Security. Both levers can be locked from inside the classroom. Provides lockdown capability without requiring the teacher to step into the corridor. Used in K-12 active-shooter response specifications.

F14 Classroom Security with Deadbolt. Adds a separate deadbolt to the F13 function for additional lockdown security.

F17 Deadbolt. Standalone deadbolt function without latch. Used on storage and tenant security applications.

F20 Entrance. Latch retracted by key outside or inside lever. Outside lever locked or unlocked by key. Used on suite entries and tenant doors.

F21 Apartment Corridor. Combines latch operation with deadbolt control specifically for multifamily corridor doors.

F31 Exit. Outside lever rigid at all times. Inside lever retracts the latchbolt. Used on emergency exit doors that don't allow re-entry from outside.

Top Commercial Mortise Lock Brands and Their Series

Five brands account for the vast majority of commercial mortise locks specified in North America. The function codes are standardized across all of them, which means model numbers cross-reference predictably once you know the function.

Schlage L Series (L9000). Allegion's flagship commercial mortise line. Over 40 functions, 31 lever designs, 14 finishes. UL listed for 3-hour fire door assemblies. The most widely specified mortise lock in North American commercial construction. The Schlage L Series parts and diagrams guide covers the component breakdown. Electrified variants include the L9580 motorized latch retraction storeroom lock for access-controlled openings.

Sargent 8200 Series. ASSA ABLOY's primary commercial mortise lock. Grade 1, full function range, broad finish and lever selection. Common on East Coast institutional specifications.

Corbin Russwin ML2000 Series. Another ASSA ABLOY brand. Functionally comparable to the Sargent 8200, often specified on legacy buildings where Corbin Russwin was the original brand.

Best 45H Series. Best Access Systems (dormakaba). Grade 1 mortise lock with field-removable core compatibility. Heavy presence in K-12 and higher-education specifications.

Yale / Accentra 8800 Series. Recently rebranded from Yale to Accentra under ASSA ABLOY. Full Grade 1 commercial mortise line.

Falcon MA Series. Allegion's mid-tier commercial mortise brand. Grade 1 performance at a different price point than Schlage L Series. Common on multifamily and budget-conscious commercial specifications.

Von Duprin 7500 Series. The mortise lock that pairs with Von Duprin 88 Series mortise exit devices. Field-reversible, field-selectable functions, electrified E7500 variant available. The Von Duprin 7500 parts manual covers the full breakdown.

Adams Rite 4500 / 4900 Series. Specialized narrow-stile mortise locks for aluminum entrance doors. Used on storefront and curtain wall applications where standard mortise hardware won't fit the door section.

Cal-Royal NM Series. Grade 1 commercial mortise at a budget tier. Used on cost-sensitive commercial and apartment corridor specifications.

Components Inside a Commercial Mortise Lock

The internal architecture is consistent across brands, even when model numbers differ. Knowing the component breakdown is what determines whether you order a complete lock or a single replacement part.

Lock case. The reinforced steel housing that contains all internal mechanisms. Field-replaceable as a complete unit on most failures.

Latchbolt. The main spring-loaded bolt that engages the strike when the door closes. Stainless steel on most production runs. Anti-friction tongue on Grade 1 units.

Deadbolt. Separate 1-inch throw bolt operated independently of the latch. Engages on key turn or thumbturn. The presence of a separate deadbolt is one of the defining features of mortise locks vs cylindrical locks.

Auxiliary latch (deadlocking). Smaller secondary latch that deadlocks the main latchbolt when the door is closed. Prevents shimming. Standard on Grade 1 commercial mortise locks.

Lever hub and spindle. The internal mechanism that translates lever rotation into latch retraction. Worn spindles cause lever droop and loose feel.

Cylinder housing. Threaded opening that accepts the keyway cylinder. Most commercial mortise locks accept Schlage-prep mortise cylinders, which means standard Everest 29, Primus, FSIC, and SFIC cylinders cross between brands.

Faceplate. The visible plate at the edge of the door covering the lock pocket. Often field-adjustable for door bevel angle.

Strike. The plate or pocket in the door frame that receives the latchbolt and deadbolt when the door closes. Specified separately from the lock body.

Trim (escutcheons and roses). The decorative and structural cover on both faces of the door. Available in various designs depending on brand.

Where Commercial Mortise Locks Are Used

Mortise locks dominate four building categories.

Healthcare facilities. Hospitals, clinics, and behavioral health buildings. Quiet operation, ligature-resistant trim options on the L Series and Sargent equivalents, and the durability to handle 24/7 cycle counts are why mortise hardware is specified here over cylindrical.

K-12 and higher education. Classrooms, administration, mechanical rooms, and lockdown-capable corridor doors. F13 Classroom Security and F14 Classroom Security with Deadbolt functions are the reason most K-12 spec sheets list mortise hardware after the Sandy Hook era specifications became standard.

Commercial office buildings. Tenant entries, suite doors, executive offices, and high-security access points. Mortise hardware is the standard on Class A office construction.

Hospitality. Hotels, conference centers, and high-end retail. The aesthetic continuity of mortise hardware (no visible faceplate from outside, clean lever and escutcheon styles) drives the spec choice.

Mortise locks are also common on government buildings, courthouses, military facilities, multifamily corridor doors, and any building where the durability premium pays back over a 20-plus year service life.

Grade 1 vs Grade 2 vs Grade 3 Mortise Locks

ANSI/BHMA A156.13 defines three grades for mortise locks based on standardized testing.

Grade 1. The highest commercial standard. Cycle test: 1 million minimum (most current Grade 1 mortise locks rate 2 million cycles). Resistance test: 1,000 inch-pounds. Door impact test passed. Used on commercial, institutional, and high-traffic openings.

Grade 2. Light commercial standard. Lower cycle and resistance requirements. Used on light commercial and high-end residential openings.

Grade 3. Residential standard. Not typically specified on commercial construction.

For commercial buildings, Grade 1 is the baseline. Grade 2 mortise locks exist but show up rarely in commercial spec because the cost gap to Grade 1 is small enough that most spec writers default to the higher grade.

How to Specify the Right Commercial Mortise Lock

Five specifications lock in every commercial mortise lock order.

Function. ANSI F-code that defines the lock behavior. Passage, privacy, classroom, office, storeroom, deadbolt, entrance, or one of the security-specific variants.

Brand and series. Schlage L9000, Sargent 8200, Best 45H, Corbin Russwin ML2000, Yale/Accentra 8800, Falcon MA, or others depending on existing building specification.

Lever or knob style. Trim selection. Lever required for ADA compliance on accessible openings. Knob still permitted on certain non-accessible commercial doors.

Finish. ANSI/BHMA finish code. 605 (bright brass), 612 (satin bronze), 619 (satin nickel), 622 (matte black), 625 (bright chrome), 626 (satin chrome), 629 (bright stainless), 630 (satin stainless), 643e (aged bronze) are the most common.

Cylinder option. P (full-face Schlage 6-pin), L (less cylinder), B (SFIC less core), R (FSIC), or one of the brand-specific cylinder variants. Cylinder choice determines key system compatibility.

Door thickness and handing are usually field-adjustable on Grade 1 mortise locks, but verify with the spec sheet. Some institutional locks require handing at order.

How to Replace a Commercial Mortise Lock

Three approaches depending on what failed.

Complete lock body replacement. When the chassis itself fails (internal mechanism worn, multiple components failed). Order the matching SKU including function, finish, and trim. Reuse the existing strike if it's in good condition.

Component-level replacement. When a single part failed (worn latchbolt, broken auxiliary latch, lever droop from spindle wear). Order the specific part. Most Grade 1 mortise lock manufacturers stock individual components.

Full re-spec to current product. When the existing lock is on a legacy series that's no longer manufactured. Schlage L9000 has been continuously produced, so retrofit is straightforward. Older Yale, Corbin, and Russwin lines may require cross-referencing to the current Accentra or Corbin Russwin equivalent.

Before ordering replacement, pull the model number off the lock face. Most commercial mortise locks stamp the brand and series directly on the faceplate or the lock body.

Why Choose Security Parts for Commercial Mortise Locks

Security Parts has been the go-to source for commercial door hardware components in the United States since 2001. That's more than two decades of stocking, shipping, and verifying parts for the exact hardware that shows up on commercial buildings. Mortise locks are a category where that experience matters more than catalog breadth, because the wrong function code on a service order costs a return cycle and a building day with the door out of service.

What sets the team apart is the depth on Allegion brands. As a long-standing distributor for Schlage, Von Duprin, LCN, and Falcon hardware, Security Parts stocks the Schlage L Series, Von Duprin 7500, and Falcon MA mortise lock components on the shelf, not on a three-week drop ship. Lock bodies, latchbolts, auxiliary latches, trim spindles, cylinder housings, and complete mortise lock assemblies ship the same day on stocked SKUs.

Spec verification is the part most distributors don't do. If you're not sure whether the existing lock is a Schlage L9050 office or an L9070 classroom, whether the cylinder option crosses between brands, or which function code matches the application, the team will work through it with you on the phone before the order ships. That's how the wrong-function return cycle gets prevented, and it's the single biggest cost-saver on commercial service calls where a misordered lock means another day of manual access on a building that doesn't have that runway.

For facility managers, locksmiths, access control integrators, contractors, and spec writers sourcing commercial mortise lock hardware across institutional portfolios, Security Parts combines stocked depth, brand specialization, and the technical bench to verify configurations. That combination is what builds the long-term sourcing relationships the team has held with K-12 districts, healthcare networks, and government facilities for over twenty years.

Closing

Commercial mortise locks are the standard hardware on every building category where security, durability, and function flexibility matter. The brand and series may vary, but the underlying ANSI function codes are universal, and the component architecture is consistent across the Big Five (Schlage L Series, Sargent 8200, Best 45H, Corbin Russwin ML2000, Yale/Accentra 8800).

When specifying or replacing a commercial mortise lock, confirm the function code first, brand and series second, then trim and finish. Source from a distributor that stocks the specific brand line your building runs on. Security Parts has carried commercial mortise lock hardware since 2001, with verified configurations and spec guidance by phone at 845-935-0301.

Frequently Asked Questions

What is the difference between a mortise lock and a cylindrical lock?

A mortise lock installs in a pocket cut into the door edge with a self-contained reinforced steel case. A cylindrical lock passes through two cross-bored holes in the door face. Mortise locks are stronger, support more functions, and last longer under commercial cycle counts.

What does ANSI/BHMA Grade 1 mean for a mortise lock?

Grade 1 is the highest commercial standard under ANSI/BHMA A156.13. It requires the lock to pass cycle testing (typically 2 million cycles), resistance testing, door impact testing, and warped door testing. Grade 1 is the baseline specification for commercial buildings.

Which is the most common commercial mortise lock brand?

Schlage L Series (L9000) is the most widely specified commercial mortise lock in North America. Sargent 8200, Best 45H, Corbin Russwin ML2000, and Yale/Accentra 8800 are the other major commercial brands.

Can mortise lock functions be changed in the field?

Yes, on most brands. Schlage L Series, Sargent 8200, and Von Duprin 7500 all support field-selectable functions on the same chassis through internal mechanism adjustments. The specific procedure varies by brand and series.

Are mortise locks fire rated?

Most Grade 1 commercial mortise locks carry UL fire ratings up to 3 hours when installed on listed fire door assemblies. Verify the specific lock's UL listing against the door's fire rating requirement.

What's the difference between a mortise lock and a mortise deadbolt?

A mortise lock combines a latchbolt and (on most functions) a separate deadbolt in one chassis. A mortise deadbolt is a leverless lock with only the deadbolt, used on auxiliary security applications. Schlage L9460 is the standard mortise deadbolt under the L Series chassis.

How long do commercial mortise locks last?

Grade 1 commercial mortise locks rated for 2 million cycles typically last 15 to 25 years in commercial service depending on traffic. Heavy-cycle openings (corridor doors, classroom entries) may need component-level service after 10 to 15 years.

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