Cylindrical locks parts and diagrams are the starting point for every field technician or facility manager who needs to replace a component without replacing the full lockset. The Schlage ND Series is the standard commercial cylindrical lock in North America, carrying ANSI/BHMA A156.2-2011, Series 4000, Grade 1 certification and UL listing for 3-hour fire doors (single 4'0" x 10'0", pair 8'0" x 10'0"). The ND Series service manual published exploded view diagrams that broke the lock into its ten primary visible components: Adjustment Plate, Outside Lever, Chassis, Latch, Strike, Anti-Rotation Plate, Optional Spacer, Mounting Screws, Inside Lever, Rose, and Inside Spring Cage. Understanding what each of these components does, what fails first in each category, and how the model number determines which parts apply to a specific installation is the knowledge base that makes parts sourcing accurate and fast.

Reading the Schlage ND Series Exploded View Diagram

The exploded view diagram in the ND Series service manual shows all ten components separated along the axis of the door, from the outside lever on the left to the inside lever and spring cage on the right, with the chassis and latch assembly in the center. This layout directly corresponds to the physical installation sequence and is the fastest way to identify a failed component visually.

Here is what each component does:

Outside Lever: The lever handle on the exterior side of the door. Lever styles for the ND Series include ATH (Athens), BRK (Boardwalk), BRW (Broadway), LAT (Latitude), LON (Longitude), OME (Omega), RHO (Rhodes), SPA (Sparta), and TLR (Tubular). Dimensions vary by style: Athens is 4.56 inches wide by 3.31 inches projection, Boardwalk is 4.94 by 3.06, Omega is 5.06 by 3.31. The Rhodes lever includes an optional breakaway feature that allows the handheld portion to separate from the shank under extreme torque, protecting the spring cage and locking mechanism from forced entry.

Chassis: The internal body of the lock that houses the locking mechanism, the cylinder interface, and the latch retractor. The chassis determines the lock function. Schlage produces separate chassis for each ND Series function (ND10, ND12, ND30, ND40, ND50, ND60, ND70, ND80, ND96, and more). Chassis are not interchangeable between functions.

Latch: The spring-loaded bolt that projects from the door edge and engages the strike on the door frame. Standard backset is 2-3/4 inches. Short backset is 2-3/8 inches. For 5-inch backset, a 43-005 extension is available. The latch includes a slide clip that the installer must engage correctly during installation: "Push latch to center of slide" is a critical step in the ND Series installation instructions that is frequently missed and produces misalignment in the latch bolt.

Strike: The frame-mounted receptacle for the latch bolt. The default Schlage ND Series strike is 10-025: ANSI, no box, 1-1/4 inch by 4-7/8 inch. Finish must be specified. For fire-rated assemblies, a T strike is available. For applications requiring a deeper pocket, a box strike provides additional latch engagement depth.

Anti-Rotation Plate: A thin metal plate that prevents the chassis from rotating inside the door bore under lever torque. On the ND Series, the anti-rotation plate tab must be aligned with the indent on the hub during installation. Misalignment produces a lock that drifts out of position over time.

Optional Spacer: Schlage provides spacers for ND Series locks installed on doors other than the standard 1-3/4 inch thickness. No spacer is required for 1-3/4 inch doors. Spacers are required for 1-3/8 inch doors. For 1-5/8 inch, 2 inch, or 2-1/8 inch doors, the adjustment plate must be repositioned rather than using spacers.

Rose: The circular cover plate that conceals the mounting hardware and the through-bore hole on the door face. Standard ND Series rose diameter is 3.44 inches. The rose is available in multiple finishes and must be finish-matched when ordering a replacement.

Inside Spring Cage: The spring cage assembly on the inside of the lock that provides lever return force and contains the button or thumbturn mechanism for inside lever control functions. When an inside lever is floppy or fails to return to horizontal, the spring cage is typically the failed component.

Mounting Screws: Two screws that draw the inside and outside trim together through the door thickness. Length must match the door thickness. XN12-012 provides standard trim chassis spacers. XN12-307 provides lead-lining spacers for special applications.

Adjustment Plate: The plate that allows the outside lever assembly to be positioned correctly relative to the door face. On ND Series locks manufactured after January 31, 2017, the adjustment plate design changed. Parts for pre-2017 and post-2017 locks are not fully interchangeable.

ND Series Function Designations: What They Mean for Parts

The ND Series function number is part of the model number and determines which chassis applies and whether electrified options are relevant.

ND10: Passage function. Latch retracted from either side at all times. No locking function. No cylinder outside.

ND12: Exit lock. Outside lever fixed (cannot retract latch). Inside lever always free. Key unlocks outside lever from outside. Electrified versions: ND12EL (electrically locked, fail safe) and ND12EU (electrically unlocked, fail secure).

ND30: Privacy lock. Push-button on inside locks outside lever. Emergency coin release from outside.

ND40: Bedroom/bath privacy. Push-button on inside locks outside lever. Emergency pin tool release from outside.

ND50 and ND53: Entrance lock. Outside lever locked/unlocked by key. Push-button on inside controls outside.

ND70: Classroom function. Key outside locks and unlocks outside lever without opening door. Inside lever always free.

ND80: Storeroom function. Outside lever always inoperative. Entry requires key only. Inside lever always free.

ND96: Combination entrance and storeroom. Available with electrified options (ND96EL and ND96EU). RX (request to exit) switch available on ND10, ND12, ND80, ND81, and ND96 functions.

Cylinder Types and Why They Affect Parts Ordering

The cylinder suffix in the ND Series model number determines which cylinder is installed:

Standard cylinder (no suffix): Conventional Schlage mortise cylinder. Uses SC1 5-pin or SC4 6-pin keyway. The standard residential and commercial specification.

FSIC (Full-Size Interchangeable Core): Allows the core to be removed and re-keyed without disassembling the lock body. The core uses a control key to insert and remove the core from the housing.

SFIC (Small Format Interchangeable Core): Best Primus-compatible small format IC standard. The core is smaller than FSIC. Common in institutional environments where a master key system uses SFIC throughout the building.

For keyed IC outside levers (FSIC only), the ND Series installation instructions include a specific note: "IMPORTANT! DO NOT install IC cylinder! Follow steps in ND-Series Timing Guide!" The timing guide must be consulted before cylinder installation on keyed IC functions. Ignoring this step is the most common cause of a new ND Series installation that does not function correctly after assembly.

The electrified ND Series uses a motor, not a solenoid, to provide quiet operation and energy efficiency. Maximum current draw is 0.24 amp, allowing more locks to run from a single power supply. The low 0.010 amp holding current eliminates the risk of lever heating in long-duration electrically locked applications.

Lock Timing and What It Means for Servicing

Certain ND Series functions require timing, meaning the position and adjustment of internal components must be set before the lock will operate correctly. Functions requiring timing are listed in the ND Series Timing Guide (P517-432), which ships with the lock.

On serviced locks where the chassis has been disassembled, the timing must be reset before the lock is reinstalled. A lock that functions mechanically but does not respond to a key, or one that operates in the wrong direction, almost always has a timing error rather than a failed component.

Sourcing ND Series Parts Accurately

Security Parts organizes the complete cylindrical locks parts and diagrams catalog with model-specific pages for the Schlage ND Series. Every parts page carries an interactive diagram aligned to the exploded view format used in the official ND Series service manual. Navigate to the function designation (ND10, ND12, ND70, etc.), open the diagram, identify the failed component visually, and confirm the part number before ordering.

The Schlage brand catalog extends this organization across every Schlage line beyond the ND Series. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com, particularly for confirming whether a lock is pre-2017 or post-2017 manufacture before ordering an adjustment plate or inside spring cage.

Conclusion

The Schlage ND Series diagram shows ten components. Each one has a specific function and a specific failure mode. The chassis is function-specific and cannot be swapped between ND10, ND70, ND80, or any other designation. The anti-rotation plate tab must align with the hub indent or the lock drifts. The latch slide clip must be engaged at center or the latch misaligns. For keyed IC functions, the timing guide must be consulted before cylinder installation. Sourcing correct cylindrical locks parts and diagrams starts with the function designation, then the cylinder type, then the door thickness, and then the finish code. Security Parts stocks every ND Series component with same-day shipping and pre-order support at 845-935-0301.

FAQs

What are the ten components in the Schlage ND Series exploded view diagram? 

Adjustment Plate, Outside Lever, Chassis, Latch, Strike, Anti-Rotation Plate, Optional Spacer (for non-standard door thickness), Mounting Screws, Inside Lever, Rose, and Inside Spring Cage.

What door thickness does the Schlage ND Series support?

 1-3/8 inch to 2-1/8 inch. Standard installation is 1-3/4 inch with no spacers required. Spacers are provided for 1-3/8 inch doors. The adjustment plate repositions for 1-5/8, 2, and 2-1/8 inch doors.

Why is the "timing guide" important for some ND Series functions?

 Certain ND Series lock functions require internal components to be set to a specific position before the lock operates correctly. The ND Series Timing Guide (P517-432) must be followed before cylinder installation on these functions, or the lock will not operate after assembly.

What is the default Schlage ND Series backset?

 2-3/4 inches standard. 2-3/8 inch short backset is available. A 43-005 extension provides a 5-inch backset for applications where the standard dimensions do not reach the door edge.

What does the RX option add to a Schlage ND Series lock?

 A micro-switch inside the chassis monitors lever rotation and signals the use of the opening to the access control system. Available on ND10, ND12, ND80, ND81, and ND96 functions.

Most facility managers only think about exit alarms parts and diagrams when the alarm fails to sound, the battery dies, or a disarming label gets peeled off. The Von Duprin Guard-X 2670 is the most widely installed commercial alarmed exit device in North America. It is not a standard exit device with an alarm kit added on. It is a purpose-built alarmed exit lock that integrates a stainless steel deadbolt rated to 1,600 pounds of force resistance, a 100-decibel alarm, an armed indicator light, and a Schlage SC-1 cylinder into a single housing. It complies with NFPA 101 Life Safety Code, is UL Listed for both panic exit hardware and fire exit hardware, carries a 10-year limited mechanical warranty and a 1-year limited electrical warranty, and ships non-handed in satin aluminum 628/US28 finish. The 2609 is the double door version.

What the Guard-X Was Built For

The Guard-X 2670 exists for one specific application: secondary exits where unauthorized use needs to be deterred without eliminating code-compliant egress. It identifies the door as an emergency exit and secures the opening against unauthorized entry or exit. Typical applications include back doors at restaurants, retail stores, discount stores, grocery stores, drug stores, clothing stores, and sporting goods stores where employee or customer misuse of a secondary exit is an operational problem.

Two features define the deterrent function:

The stainless steel deadbolt does not retract unless the key disarms the device first. It is tested to withstand 1,600 pounds of force, making it significantly more resistant to defeat than a standard latch bolt. The 100-decibel alarm sounds immediately when the push bar is activated without prior key disarming. The armed indicator light on the device face shows the armed state before any attempt is made to open the door.

The standard device ships with an SC-1 Schlage cylinder included. The 2609 double door variant coordinates alarm functions between two active leaves on a paired opening.

Every Replaceable Component in the Guard-X 2670

Alarm Battery

This is the most frequently replaced component on every Guard-X installation. The device uses a standard 9-volt battery to power the alarm circuit. When the battery fails, the device operates mechanically but produces no alarm sound on push bar activation, which is the worst failure mode for a deterrent device. Proactive replacement every six months on high-use secondary exits prevents silent failure without waiting for the symptom.

Schlage SC-1 Cylinder

The cylinder is what disarms the alarm before an authorized door use. The SC-1 keyway is Schlage's standard 5-pin tumbler residential and light commercial cylinder. It ships included with the Guard-X 2670. Replacement is needed when the cylinder wears from heavy use, when a key is lost, or when the building's key system is being re-keyed. The SC-1 keyway is widely available from Schlage-authorized locksmiths and can be ordered factory-keyed to a master key system.

Retainer Nut

The retainer nut secures the cylinder in the device housing. A loose retainer nut allows the cylinder to rotate in the housing rather than staying fixed, which prevents the alarm from disarming correctly when the key is turned. Retainer nuts are the most commonly overlooked service item on Guard-X devices. A torque check at every service visit takes 30 seconds and prevents the most frustrating "alarm won't disarm" service call.

Disarming Label

The "EMERGENCY EXIT ONLY, ALARM WILL SOUND" label is both an NFPA 101 code requirement and a deterrent element. Labels fade, peel, or are deliberately removed. A missing label removes a code compliance element and reduces deterrent effectiveness. Replacement labels are stocked individually.

Alarm Housing Assembly

The housing contains the sounder element and the circuit board that controls alarm timing and the indicator light. When the alarm sounds erratically, fails to sound despite a fresh battery, or the indicator light malfunctions, the housing assembly requires replacement. This is less common than battery or cylinder service but becomes necessary as devices age past their electrical warranty period.

Push Bar Assembly

The push bar completes the alarm circuit when depressed without prior disarming. Push bar wear from physical abuse or forced entry attempts requires assembly replacement. The push bar is replaceable without removing the full device from the door.

Deadbolt Assembly

The stainless steel deadbolt is the mechanical security element. Replacement is required when the bolt is physically damaged from a forced entry attempt significant enough to defeat the 1,600-pound resistance rating. This is not common but does occur in high-risk retail applications.

Sourcing Guard-X Parts at Security Parts

Security Parts organizes the complete Guard-X exit alarm parts catalog with model-specific components for the 2670 and 2609. The Von Duprin brand page covers the Guard-X alongside every other Von Duprin exit device series. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com. Same-day shipping on stocked components.

Conclusion

The Von Duprin Guard-X 2670 is a purpose-built alarmed exit device with a 10-year mechanical warranty and a 1-year electrical warranty. Six primary replaceable components: 9-volt alarm battery, Schlage SC-1 cylinder, retainer nut, disarming label, alarm housing assembly, and push bar assembly. The battery is replaced most often. The retainer nut is inspected least often. The 2609 double door version shares all the same component specifications. Sourcing from the exit alarms parts and diagrams catalog at Security Parts starts with confirming single door (2670) or double door (2609), then navigating to the model-specific parts page with same-day shipping on stocked items.

FAQs

What alarm volume does the Von Duprin Guard-X produce? 

100 decibels. It activates immediately when the push bar is pressed without prior key disarming. The armed indicator light shows armed status before any door use attempt.

What force resistance does the Guard-X deadbolt have? 

1,600 pounds, per Von Duprin testing. This significantly exceeds standard latch bolt resistance and prevents the door from being forced open without triggering the alarm first.

What battery does the Guard-X 2670 use? 

A standard 9-volt battery. Replace proactively every six months on high-use secondary exits. Battery failure causes silent operation with no alarm on push bar activation.

What cylinder ships with the Guard-X 2670?

 A Schlage SC-1 5-pin tumbler cylinder. Re-keyable by any Schlage-authorized locksmith. Can be ordered factory-keyed to a building's master key system.

What warranty does the Guard-X carry?

 10-year limited mechanical warranty, 1-year limited warranty on electrical components.

Most maintenance teams only think about door closers parts when a closer arm cracks, a cover plate falls off, or the door starts slamming hard enough to loosen the hinges. By that point, the device has usually been failing gradually for weeks. A sweeping door that moves inconsistently, a latch that engages but does not pull cleanly, a door that drifts open when the building pressurizes, these are all early signals from a specific component that is wearing out. LCN, manufacturing commercial door control hardware since 1877, produces the most widely installed institutional closer line in North America. Its parts catalog spans surface-mounted closers (1460, 4040XP), overhead concealed closers (3030/3130, 2010/5010), high-security closers (2210), and the COMPACT operator (6400). Every component in every series is ordered with four specifications: Finish (F), Size (S), Hand (H), and Voltage (V) where applicable. Missing any one of them produces a part that ships incorrectly.

How to Find the Model Number Before Opening the Parts Catalog

The model number on LCN mechanical closers is stamped near the packing nut at the base of the pinion shaft, where the arm connects to the closer body. The month and year of manufacture are also stamped there. For concealed closers and automatic operators, the information is on a label on the housing.

One thing that trips up a lot of first-time LCN parts orders: casting and forging numbers stamped or raised on the component surface, such as "71" or "320G" on a cylinder assembly, are manufacturing reference numbers, not part numbers. They cannot be used to identify or order a replacement. Use the model number from the closer body and the current LCN parts manual for correct identification.

The Seven Component Categories That Cover Most LCN Door Closer Repairs

Arm Assemblies

The arm is the most frequently replaced component on surface-mounted LCN closers. It connects the closer body to the door or frame and translates spring energy into controlled door movement. Arm failure most often presents as a cracked casting at the pivot point or a stripped connection at the shoe.

LCN produces several arm configurations across the surface-mounted lineup:

• Regular arm (3077): The standard pull-side arm. Connects the closer body to the frame with a fixed pivot. Used in regular arm mounting where the closer is on the pull side of the door.
• Parallel arm with shoe (3027PA): For push-side door face mounting. The arm runs parallel to the frame when the door is closed, protecting it from direct force and reducing projection.
• Slide track arm (3077T): Rides in a track mounted to the frame. Allows hold-open at any door position. The track roller is a separate serviceable component.
• Extra duty arm (EDA): Reinforced construction for abuse-resistant applications.
• Fusible link arm: For fire-rated hold-open applications where the arm releases and allows the door to close when a heat-sensitive fusible link melts.

For the 4040XP specifically, the standard regular arm is 4040XP-3077 and the parallel arm drop plate combination is 4040XP-18PA. For the 3130 concealed closer, the track arm is 3130-3034, with the track roller as a separate part at 3130-3034-689.

The long rod and shoe combination 4040XP-79LR covers applications where the standard arm cannot reach the required frame mounting point due to door width or frame geometry.

Cover Plates and Body Housing

The cover protects the internal hydraulic and spring mechanism. On the 4040XP, the metal door closer cover is right-hand (RH) and left-hand (LH) specific. The 4040SE series uses a 4040SE-72MC-RH-689 metal cover for right-hand installations.

Cover plates are finish-specific. When ordering a replacement cover, the finish code must match the installed hardware. Standard LCN finishes include 689 (aluminum), 693 (bronze), 690 (dark bronze), and 628 (satin aluminum).

Drop Plates and Mounting Hardware

Drop plates reposition the closer body when the standard mounting geometry cannot be used due to a window transom, a non-standard header dimension, or a frame profile that does not accommodate direct mounting. The 4040XP-18PA is the parallel arm drop plate for top rail-less applications. Drop plates are application-specific and cannot be substituted between different mounting configurations.

Mounting screws are door-material specific. Metal door mounting uses machine screws. Wood door mounting uses wood screws. Using incorrect fasteners creates play in the installation that accelerates wear on every internal component.

Cylinder Assembly and Pinion

The cylinder assembly is the internal hydraulic unit inside the closer body. It contains the piston, the spring, and the hydraulic fluid that controls the closing speed. On standard surface closers, the cylinder is not individually serviceable: when the hydraulic fluid leaks from the body or the internal seals fail, the entire unit requires replacement rather than component repair.

The packing nut sits at the base of the pinion shaft. The pinion is the shaft that connects the arm to the internal spring mechanism. If the arm is secure but the door does not close properly, the pinion connection is a point to inspect before condemning the full unit.

Track Roller

The track roller is the component that rides inside the slide track on track arm closers. It is one of the highest-wear components on track arm installations because it absorbs the rotational force of every door cycle through direct contact with the track surface. Squealing or scuffing sounds during closer operation are the most common indicator of a worn track roller.

LCN track rollers are series-specific:

• 4010T-3034: For the 4010T surface closer
• 3130-3034-689: For the 3130 concealed closer
• 4630-3034-689: For the 4630 Auto Equalizer operator
• 2030-3034H: For hold-open or non-hold-open track configurations on the 2030 concealed closer

Spring and Green Dial Adjustment (1460 Series)

The LCN 1460 Series includes the patented Green Dial spring power adjustment system. This allows the spring power to be adjusted in the field without disassembling the closer body. The Green Dial eliminates the need to stock multiple spring sizes to cover different door weights and backcheck requirements. When the door is closing with inadequate force or latching inconsistently, adjusting the Green Dial is the correct first step before ordering any replacement component on a 1460 Series closer.

For closers without the Green Dial, the spring power is determined at the time of order and is set internally at the factory. Field adjustment of spring power on these models requires replacement of the entire cylinder assembly.

Sentronic Electronic Hold-Open Arm

The LCN Sentronic series integrates an electronic hold-open function into the door closer arm. When powered, the arm locks in the hold-open position. When power is interrupted (by a fire alarm signal, for example), the arm releases and the closer brings the door to the latched position. The Sentronic arm hold-open track is a replaceable component: 4040SEH-3038 is the 24V hold-open track, non-handed, non-sized.

What Failure Signs Map to Which Component

Sourcing LCN Closer Parts Correctly

Security Parts organizes the complete door closer parts catalog by series with interactive diagrams on every model page. The LCN door closer parts guide covers the full component tree for surface-mounted, concealed, and COMPACT operator models. The four ordering specifications, Finish (F), Size (S), Hand (H), and Voltage (V), are required for every finish-specific, size-specific, handed, or electrified component. Confirming all four before placing the order is what prevents the most common wrong-part returns on LCN products.

Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

LCN door closers parts are series-specific, finish-specific, and in many cases hand-specific. The model number is at the packing nut. Casting numbers on components are not part numbers. Track rollers, arm assemblies, cover plates, and Sentronic hold-open tracks are the most common individual replacement components. The Green Dial spring adjustment on the 1460 Series should be the first adjustment attempted before any parts order on a 1460 closer with inconsistent closing behavior. Every parts order requires Finish, Size, Hand, and Voltage specifications. Security Parts stocks every LCN series component with same-day shipping on in-stock items and pre-order support at 845-935-0301.

FAQs

Where is the LCN door closer model number located? 

Stamped near the packing nut at the base of the pinion shaft on mechanical closers. The manufacturing date is also stamped there. For concealed closers and automatic operators, the information is on a label on the housing.

Are casting numbers on LCN components the same as part numbers? 

No. Numbers like "71" or "320G" stamped on LCN cylinder assemblies are manufacturing reference numbers and cannot be used to order replacement parts. Use the model number from the closer body and the LCN parts manual.

What four specifications are required to order an LCN door closer part? 

Finish (F), Size (S), Hand (H), and Voltage (V) where applicable. Missing any one of these produces an incorrectly specified part.

What causes the squealing sound on an LCN track arm door closer? 

Track roller wear from high-cycle use. The track roller is a serviceable replacement component specific to each LCN series. It is not universal across series models.

What is the LCN Green Dial?

 A patented spring power adjustment system on the 1460 Series that allows the spring power to be adjusted in the field without disassembling the closer body, eliminating the need to stock multiple spring-size closers.

When deadbolts parts need replacing on a commercial building, the sourcing process has one non-negotiable starting point: knowing the exact Schlage B Series model installed, because the cylinder type, the backset, the strike dimensions, and the tailpiece profile all vary between the B250, B260, B350, and B360 lines. The Schlage B Series has been the commercial and institutional deadbolt standard for decades. It carries ANSI/BHMA Grade 1 and Grade 2 ratings depending on the model, a 1-inch deadbolt throw on Grade 1 configurations, and a parts catalog that has remained largely consistent, which means a component ordered today is compatible with a B Series deadbolt installed in the 1990s. But getting the specific part right still requires reading the model number, confirming the backset, and knowing which cylinder type is installed before anything goes in a cart.

The Schlage B Series Lineup and What Separates Each Model

Understanding which model is installed determines every subsequent parts decision.

B250 and B252: The Grade 1 single-cylinder deadbolt (B250) and double-cylinder (B252). Single cylinder means inside thumbturn, outside key. Double cylinder means key operation on both sides. The 1-inch throw bolt meets Grade 1 bolt extension requirements. The B252 is the specification for glass-panel doors and applications where reaching through a broken pane to operate a thumbturn is a security concern.

B350 and B352: The commercial Grade 2 versions of the same configurations. 5/8-inch throw bolt rather than 1 inch. Specified on lower-security applications where Grade 1 performance is not required.

B360: The vertical deadbolt, where the bolt throws vertically rather than horizontally. Specified on applications where a door is subject to prying force that could defeat a horizontal bolt, common on hollow metal exterior doors with minimal frame engagement.

The backset is the distance from the door edge to the center of the cylinder hole. Schlage B Series ships standard at 2-3/8 inch and 2-3/4 inch backsets. Confirming which backset is installed is the sourcing step that determines the correct latch and strike combination.

Every Replaceable Component in the Schlage B Series

The Deadbolt Cylinder

The cylinder is the component that translates the correct key into bolt rotation. It is the most commonly replaced part in the Schlage B Series because it absorbs the wear of every key insertion and rotation across the deadbolt's service life.

Schlage B Series cylinders are available in several configurations:

Standard 5-pin cylinder (SC1 keyway): The residential and light commercial standard. The SC1 "C" keyway is the most widely available and the most easily rekeyed in the field.

6-pin cylinder (SC4 keyway): Provides one additional pin stack for slightly increased pick resistance. Specified where a small security upgrade is required without changing the entire keyway system.

Primus high-security cylinder: Incorporates an additional set of side pins and a sidebar mechanism, requiring a key with a corresponding milled channel. Significantly increases resistance to picking and unauthorized key duplication. The Primus cylinder cannot be picked or bumped by standard methods and the keyway is patented, meaning unauthorized key copying requires a certified dealer.

The cylinder is held in the deadbolt body by a small set screw or retaining pin typically located on the side of the bolt assembly near the cross bore hole. The tailpiece, the flat metal bar extending from the back of the cylinder, must be correctly oriented to engage the bolt rotation mechanism when the replacement cylinder is installed.

The Latch Bolt and Throw Assembly

On Grade 1 B Series models, the deadbolt itself is a 1-inch hardened steel bolt with an anti-saw pin. On Grade 2 models, the throw is 5/8 inch. The bolt housing contains the mechanism that converts rotational motion from the cylinder or thumbturn into the horizontal throwing action of the bolt.

Latch bolt failure is typically caused by physical damage from door slamming against a misaligned strike rather than from internal component wear. A bent or deformed bolt that does not retract cleanly is the most common indicator.

The Strike Plate

The Schlage B Series ships with several standard strike options. The specific strike needed for any replacement order depends on the door frame material, the backset, and whether a security strike upgrade is required.

• 10-025: ANSI standard strike, no box, 1-1/4 inch by 4-7/8 inch. The standard specification strike for most commercial applications.
• 10-026: Full lip strike, 1-5/8 inch by 2-1/4 inch, square corners. Used where a shorter lip is acceptable and the door frame does not accommodate the full ANSI strike.
• 10-027: Full lip strike, 1-5/8 inch by 2-1/4 inch, 1/4-inch radius corners. Aesthetic version of the 10-026 for applications where corner radius is specified.
• B520283 Dust Box: The standard deadbolt strike dust box that mounts in the door frame strike cutout, providing a pocket for the bolt to enter and protecting the frame material. Finish must be specified.

The Thumbturn

The thumbturn is the interior component that operates the bolt without a key on single-cylinder models. Thumbturn failure is usually caused by the mechanism wearing out at the pivot point or by physical force applied to the inside of the door. The Schlage B Series thumbturn assembly connects directly to the bolt mechanism and is a field-replaceable component.

Spindle and Rose Plate

The rose plate covers the cylinder hole and mounting hardware on the door face. On the B Series, the exterior rose plate is available in multiple finishes and must be finish-matched when ordering a replacement. The spindle connects the thumbturn to the internal bolt mechanism on single-cylinder models.

Mounting Screws

The B Series ships with mounting screws specific to the door thickness. Standard screws cover 1-3/4 inch doors. The Schlage 61-075 thick door kit provides longer screws and mounting extensions for doors up to 2-1/4 inches thick, used when the standard screws do not provide adequate bite.

Common Failure Signs and What Each Indicates

Cylinder turns but bolt does not move: The tailpiece is not engaging the bolt mechanism correctly. Either the replacement cylinder has the wrong tailpiece orientation or the internal bolt mechanism has worn out.

Bolt extends but does not retract cleanly: Typically indicates a bent bolt, a deformed strike pocket, or door frame movement that misaligns the bolt and strike. The strike should be removed and the alignment checked before replacing any internal components.

Key difficult to turn but still operates: Pin stack wear inside the cylinder, or a bent key that has deformed the driver pins. A cylinder replacement addresses both causes.

Bolt not extending to full throw: Internal spring fatigue inside the bolt mechanism, or physical interference from frame material swelling around the strike box.

Thumbturn loose or clicking: The thumbturn pivot spring has failed. The spring assembly is replaceable without removing the full cylinder.

Why Finish Must Be Specified on Every Schlage B Series Parts Order

Every finish-specific Schlage B Series part, including the rose plate, strike, thumbturn, and exterior trim, requires a finish designation when ordering. Standard Schlage finishes include US26D (satin chrome), US26 (polished chrome), US3 (polished brass), US4 (satin brass), US10B (oil-rubbed bronze), US10 (satin bronze), and US15 (satin nickel). Ordering without a finish designation produces a part that ships in the manufacturer's default and may not match the installed hardware. The model number on the installed deadbolt usually includes the finish code as the last designation in the number.

Sourcing Schlage B Series Parts at Security Parts

Security Parts organizes the complete Schlage deadbolt parts catalog by model, with each B Series model on its own page. The Schlage brand catalog covers every active Schlage line with the same model-specific structure. For deadbolts installed in multi-family, healthcare, or government applications where the cylinder is part of a master key system, confirming the keyway before ordering a replacement cylinder is essential. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

Schlage B Series deadbolts are the most widely installed commercial deadbolts in North America, and their deadbolts parts catalog has remained consistent enough that components sourced today apply to devices installed years ago. The cylinder keyway, the bolt throw length, the backset, the strike dimensions, and the finish code are the five variables that determine every parts order on these devices. Confirming them from the model number on the installed deadbolt is the step that keeps a straightforward maintenance job from becoming a return cycle. Same-day shipping on stocked components. Pre-order support at 845-935-0301.

FAQs

What is the bolt throw length on a Schlage Grade 1 B Series deadbolt?

 One inch. The Grade 1 B250 and B252 models project a 1-inch hardened steel deadbolt with an anti-saw pin. Grade 2 models (B350/B352) use a 5/8-inch throw.

What is the difference between a single-cylinder and double-cylinder Schlage deadbolt?

 Single-cylinder (B250, B350) uses a thumbturn inside and key outside. Double-cylinder (B252, B352) requires a key on both sides, specified where inside key override through a broken pane is a security concern.

What Schlage B Series strike is standard for commercial applications? 

The 10-025 ANSI strike, 1-1/4 inch by 4-7/8 inch, no box, is the standard commercial specification. Finish must be specified when ordering.

Why won't my Schlage cylinder turn after replacement? 

The tailpiece orientation is incorrect. The tailpiece must be aligned to engage the bolt rotation mechanism before the set screw is tightened. Refer to the Schlage B Series installation instructions for the correct tailpiece position for the specific function.

What is the Schlage Primus cylinder?

 A high-security cylinder with side pins and a sidebar mechanism requiring a milled channel on the key. Significantly more resistant to picking and bumping than standard 5-pin cylinders. Available as a factory-specified cylinder on B Series commercial applications.

If you're maintaining commercial doors, mortise locks parts are among the most complex components you'll source. The Schlage L Series alone covers more than 67 mechanical functions, 33 lever designs, and 12 finishes, and its parts tree splits 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. The mortise cylinder cam that applies to a standard Schlage mortise cylinder does not apply to a modular mortise cylinder. And the escutcheon trim on one function may need to be replaced entirely if the function changes, while the rose (sectional) trim on the same door requires no additional parts. Getting any one of these wrong wastes a service call and delays a repair on a door that may be in a fire stair, a healthcare corridor, or a government facility.

How to Read a Schlage L Series Model Number

The model number decodes every specification needed to source replacement parts correctly. The format follows this structure:

L / LV + function group + deadbolt indicator + cylinder suffix

• L = standard L Series chassis
• LV = Vandlgard chassis, designed for applications subject to abuse or vandalism. The Vandlgard prevents damage to internal lock components caused by forced lever manipulation.
• Function group (e.g., 9080): The specific lock function. L9080 is the storeroom function where the outside lever is always inoperative, entry requires a key, and the inside lever is always free. L9010 is passage. L9050 is entrance/office. L9070 is classroom.
• Deadbolt indicator: 0 in the function number means no deadbolt. 4 means with deadbolt. L9460 Series adds a deadbolt to the basic functions.
• Cylinder suffix: P = 6-pin full-face mortise cylinder with Schlage logo. L = less cylinder. C = concealed mortise cylinder. W = less concealed cylinder. R = full-size interchangeable core.

The L9050 universal case is worth a specific note: Schlage designed it to be transformed into nine different functions with just a few additional parts. This means a facility that stocks the L9050 universal case can reconfigure it for multiple function requirements with the appropriate additional components rather than stocking nine separate cases.

The Six Component Categories in Mortise Lock Parts

Lock Chassis and Internal Components

The chassis is the case body that houses all internal mechanism components and mounts inside the door edge mortise pocket. The standard L Series chassis and the Vandlgard LV chassis are dimensionally compatible but use different internal component tolerances designed for different use environments.

Internal components commonly replaced include:

• Latchbolt with anti-friction tongue: The primary latch that engages the strike. The anti-friction tongue releases easily when the door is pushed closed, then the full latch bolt projects. This protects the strike face from wear on high-cycle openings.
• Auxiliary guarded latch: Deadlocks the latchbolt when the door is fully closed, preventing credit card or shimmy-type forced entry. Present on most L Series functions.
• Deadbolt: Present on L9460 and related deadbolt functions. Operated by thumbturn from inside or key from outside.
• Stopworks functions by turn-piece: A mechanical stop mechanism on specific functions that prevents the thumbturn from being operated from outside.

Lever Return Spring (L283-040)

The L283-040 lever return spring is one of the most commonly replaced individual components in the Schlage L Series. It returns the lever to the horizontal position after being operated. One spring is required for each side of the door where a lever is installed. On a standard L9050 entrance function with levers on both sides, two springs are required.

Spindle and Spring Assembly (L283-060)

The L283-060 spindle and spring assembly is used on standard L Series mortise locks for door thicknesses of 1-3/8 to 1-7/8 inches. The spindle is the shaft that connects the trim lever to the internal lock mechanism. When a lever operates but the latch does not retract, the spindle or its connection to the retractor is usually the fault point.

Cylinder Components and Cams

The mortise cylinder sits in the cylinder hole in the chassis face and operates the lock from outside with a key. The cam on the back of the cylinder is what translates rotation into the lock's retractor movement. The correct cam depends on the cylinder type and the lock function.

• L583-254: Mortise cylinder cam for standard Schlage L Series cylinders (not modular). Fits on the back of conventional Schlage mortise cylinders.
• L583-446: Replacement cam for Schlage modular mortise cylinders. Works with cylinder lengths 1-1/8, 1-3/8, and 1-5/8 inches.
• L583-476: Alternative standard cam for Schlage modular mortise cylinders.
• K510-730: Standard cam for IC (interchangeable core) housings. Also works with Schlage K Series (discontinued), Falcon non-deadbolt functions, Von Duprin exit devices, and Adams Rite 2331 deadlocks.

The cam type must match the cylinder type installed. Using a standard cam on a modular cylinder or an IC cam on a conventional cylinder produces a lock that either fails to operate or operates in the wrong direction.

Trim Components: Rose vs Escutcheon

Trim covers the lever mounting hardware visible on the door face. Schlage L Series offers two trim types with different parts implications:

Rose (sectional) trim: Individual circular rose plates that mount the lever to the door. When servicing rose trim, the existing rose trim hardware does not need to be replaced for function changes in most cases. The lock chassis underneath can be updated to a new function with the appropriate internal parts.

Escutcheon trim: Full-length plates that cover the lever and cylinder area. When changing functions on escutcheon-trimmed locks, both inside and outside escutcheons may need to be replaced. The L Series installation instructions are specific about which functions require full escutcheon replacement.

Specific trim parts include:

• 09-509 Thumbturn: The standard Schlage L Series T-turn in satin chrome (626). Replaces a worn or damaged thumbturn that operates the deadbolt or privacy deadlocking function.
• L285-150 Mounting Plate: Used on institutional functions (L9080, L9082) where the inside lever is installed without a thumbturn. Required when the chassis is in the locked position and the inside lever must be mounted separately.
• Shear pin: The component designed to break if the lever handle is forced. Protects the trim assembly from destruction. Used across multiple L Series trim configurations.

Strikes

The L Series strike selection depends on the door type (wood vs hollow metal), the frame material, and whether a fire-rated strike is required. Strike types include T-square corner strikes, flat square corner strikes, rabbeted strikes for rabbeted frames, and the L9000 Series-specific deadbolt strikes. Finish must be specified when ordering any strike.

Function-Specific Parts and the Universal Transformation

One of the most useful and most overlooked features of the L Series for facilities teams is the universal transformation capability of the L9050 case. Schlage designed this case so that nine different functions can be achieved from a single case with specific additional parts. This means a facility manager maintaining a building with multiple L Series functions can stock a single case type and adapt it to the function required, rather than keeping nine different cases in inventory.

The transformation instructions specify exactly which additional parts are required for each function conversion and whether the existing trim components transfer or need to be replaced. Some functions require the thumbturn assembly to be removed. Some require the clover leaf cylinder cam to be replaced with a straight cam. The instructions are function-specific and available in the Schlage Universal Transformation Guide.

Why Model-First Sourcing Matters for Mortise Lock Parts

Mortise lock parts from a general catalog listing present the same compatibility risk as exit device parts. A lever return spring listed as "L Series spring" without the specific part number and function context could apply to any of 67 mechanical functions. A cam listed as "mortise cylinder cam" without specifying whether it applies to standard or modular cylinders produces an incompatible part.

Security Parts organizes the complete mortise locks parts catalog with model-specific pages for the Schlage L Series and supporting hardware. The Schlage brand catalog covers every active Schlage lock line with the same model-specific organization. The Schlage L Series parts and diagrams page carries interactive diagrams for L Series mortise lock models organized by function group.

Pre-order compatibility support is available at 845-935-0301 or sales@securityparts.com, particularly useful for identifying the correct cam type, confirming the spindle length for the door thickness, or identifying which trim parts transfer when a function changes.

Conclusion

The Schlage L Series is the most flexible and most parts-intensive mortise lock line in commercial hardware. More than 67 functions, 33 lever designs, and a chassis that can be transformed into nine configurations from a single case. Sourcing any component correctly requires reading the model number (L vs LV, function group, deadbolt indicator, cylinder suffix), identifying whether rose or escutcheon trim is installed, confirming whether the cylinder is standard or modular before selecting a cam, and knowing whether the specific function requires a mounting plate or a shear pin for correct assembly. Starting with the mortise locks parts catalog organized by model and function at Security Parts, using the interactive diagram to confirm each component visually, is what makes the repair accurate without a service callback.

FAQs

What is the difference between the Schlage L Series and LV Series chassis? 

The L is the standard chassis. The LV (Vandlgard) is for abuse-prone environments, engineered to prevent damage to internal components from forced lever manipulation. Dimensionally compatible but with different internal tolerances.

What is the Schlage L9050 universal case?

 The L9050 universal case can be transformed into nine different lock functions with specific additional parts, allowing a single case to serve multiple function requirements without stocking nine separate cases.

How do I identify the correct mortise cylinder cam? 

L583-254 is for standard Schlage L Series conventional mortise cylinders. L583-446 and L583-476 are for modular mortise cylinders. K510-730 is for IC housings. Cam selection depends on which cylinder type is installed.

What is the Schlage L283-040 lever return spring? 

It is the spring that returns the lever to the horizontal position after being operated. One spring is required for each lever installed. Available for individual replacement without disassembling the full chassis.

When does escutcheon trim need to be replaced on a function change?

 On escutcheon-trimmed L Series locks, both inside and outside escutcheons may need replacement when the lock function changes. Rose (sectional) trim typically does not require replacement for function changes.

What is an auxiliary guarded latch on a mortise lock? 

A secondary latch that deadlocks the primary latchbolt when the door is fully closed, preventing credit card or shimmy-type forced entry. Present on most Schlage L Series functions.

Door operators parts are not the same as door closer parts, even when the operator uses a mechanical closer as part of its assembly. An automatic door operator is an electromechanical or electrohydraulic system that includes a motor or hydraulic drive unit, a controller, an arm assembly, an actuator, and a power supply, all working together to open and hold a door on a signal. When one component in that chain fails, the symptom can look like any one of several issues: the door opens too slowly, it reverses before fully opening, it fails to latch on closing, it makes grinding or squealing sounds, or it simply stops responding to the actuator. Each symptom points to a different component category, and sourcing the replacement correctly requires knowing which category is responsible. LCN, manufacturing commercial door control hardware since 1877, produces the most widely installed commercial automatic door operator line in North America. This guide covers every LCN door operator component category, what failure looks like in each one, and how to source accurately.

Understanding the Four LCN Door Operator Series

Parts compatibility in LCN door operators is series-specific, which means the first diagnostic step is confirming which series is installed. The date of manufacture label is on the operator body. For automatic operators, LCN places it on the label itself rather than stamping it near the packing nut as on mechanical closers.

LCN 4630/4640 Auto Equalizer Series: Designed for primarily manual applications that sometimes require automatic opening, primarily for accessibility. The 4630 mounts top jamb on the pull side with a single lever track arm. The 4640 mounts top jamb on the push side with a double lever regular arm. Both carry ANSI/BHMA 156.19 certification, UL and cUL listing, and ADA/ANSI A117.1 compliance. The "No Destruct" drive system is a specific feature of this series, providing resistance to mechanical damage from forced opening or door being held open against the operator.

LCN 9130/9140/9150 Benchmark Series: The low-to-medium traffic surface-mounted operator line. The 9130 mounts on the pull side with a single lever track arm. The 9140 mounts on the push side with a double lever arm. The 9150 mounts top jamb on the push side for independent or simultaneous pair applications. Features Push 'N Go activation, which takes over when a pedestrian manually opens the door to 5 degrees, then holds the door fully open for 1 to 30 seconds of adjustable time delay. Power Boost provides additional closing force under wind load.

LCN 6400 COMPACT Series: The low-energy operator designed for retrofitting existing LCN 4040XP Series mechanical closers. The motor gearbox assembly connects to the existing 4040XP with just four screws and a mounting plate. This is the most cost-effective way to automate an existing opening without removing and replacing the mechanical closer already installed. The existing 4040XP closer cylinder, including delayed action models, remains in place. Electronic features including opening speed, hold open duration, power boost, motor on/off, fire signal receipt, and actuation signal receipt are all configurable.

LCN Senior Swing Series (9500IQ/2800IQ): The current-generation high-performance operator featuring AdaptivIQ technology, which continuously self-adjusts the operator's opening and closing parameters to account for seasonal temperature changes, door weight variations, and wind load. The 9500IQ is the surface-mounted version. The 2800IQ is the concealed version. Both reduce seasonal service calls because the electronic controller compensates for environmental changes without manual valve adjustment.

The Seven Component Categories in LCN Door Operator Parts

Motor Gearbox Assembly

The motor gearbox is the drive unit that physically opens the door. On the COMPACT Series, the motor gearbox assembly mounts directly onto the 4040XP Series closer body. On the Auto Equalizer and Benchmark Series, it is integrated into the operator housing. The gearbox converts motor rotation into arm movement through a gear reduction system. When the motor runs but the door does not open, the gearbox is the first component to inspect.

Track Arm Assemblies

LCN produces several arm configurations for door operators, each designed for a specific mounting and door type:

• Standard track arm: rides in a track mounted to the door frame, allowing hold-open at any position
• Double lever arm: fixed pivot configuration for push-side mounting
• Single lever track arm: for pull-side and top jamb applications
• Long arm: for doors requiring extended reach from the closer body to the frame

The 4630 Series track roller part is LCN 4630-3034-689. The standard track is LCN 4630-3038-689. These are finish-specific and must be specified when ordering. Arm compatibility is series-specific: a 9500IQ arm assembly does not cross to the 4630/4640 series.

Controller and Digital Control Box

The controller is the electronic brain of the door operator. It manages opening speed, hold-open duration, power boost threshold, fire alarm interface, and actuator signal input. The 4630/4640 Series digital control box provides fast and accurate adjustments with a physical interface. The Senior Swing's controller runs the AdaptivIQ algorithm, which means it stores learned parameters. When a controller fails, these parameters are lost and must be recalibrated after replacement.

The LCN 9550 Series controller replacement part is 9550-3462-115V for the 115V version. Controllers for the COMPACT 6440 Series are available as part of the COMPACT Low Energy Auto Door Operator Module Parts Kit (LCN 6440).

Actuators: Push Plates and Touchless Sensors

The actuator is what signals the operator to open. Push plate actuators require physical contact. LCN's 8310 Series touchless actuators detect hand motion within sensor range, triggering the opening cycle without physical contact. The 8310-865 is a compact receiver that complies with federal radio frequency regulations and receives signals through barriers.

Two wireless options are available: 900 MHz and 433 MHz, providing wireless actuation without hardwiring the actuator directly to the operator. Both are compatible with LCN's touchless actuation offerings.

Actuator failure typically presents as a door that does not respond to the push plate but operates correctly when tested through a direct controller signal. This isolates the actuator circuit rather than the operator itself.

Power Supply

Door operators require a dedicated power supply. On low-energy operators like the COMPACT and Benchmark Series, the power supply is typically 120V AC or 24V DC depending on the installation. Power supply failure produces a completely non-functional operator even when all other components test correctly. The power supply should be the first component checked when an operator stops responding entirely.

Spring and Hydraulic Components (Mechanical Elements)

For operators that incorporate a mechanical closer as part of the assembly (specifically the COMPACT Series using the 4040XP), the mechanical closer components remain serviceable independently of the motor assembly. The 4040XP cylinder, spring, and hydraulic valves can be adjusted or replaced without disassembling the operator module. Existing 4040XP components including delayed action cylinders are compatible with the COMPACT operator.

Sensors and Accessories

Motion sensors, hold-open sensors, and safety sensors are auxiliary components that affect operator behavior without being part of the drive assembly. A safety sensor detecting an obstruction will prevent the door from fully closing. A malfunctioning hold-open sensor may cause the door to close prematurely. The 8310 Series sensor accessories are designed to integrate with LCN's touchless and automatic operator lineup.

How to Identify a Failed Component Before Ordering

A door that opens too slowly with normal sound usually indicates a spring or valve adjustment, not a parts failure. A door that makes grinding or squealing during operation typically needs the arm and track assembly inspected for wear or misalignment. A door that opens but fails to latch points to the mechanical closer components, particularly the latch speed valve or the latch bolt engagement on the paired lock. A door that fails to respond to the actuator but works on manual override points to the actuator or controller circuit, not the motor. A door that operates once but does not reset for the next cycle is often a power supply issue.

Why Model-Specific Sourcing Prevents the Most Common Errors

LCN operator parts are finish-specific, size-specific, and in many cases voltage-specific. LCN's own guidance on ordering requires specifying Finish (F), Size (S), Hand (H), and Voltage (V) for any part where these variables apply. Missing any one of them produces a part that ships but does not fit or does not function in the installation.

The casting or forging numbers stamped on LCN components, such as "71" or "320G" on cylinder assemblies, are manufacturing reference numbers, not part numbers. They cannot be used to order a replacement. The model number on the operator body and the current LCN parts manual are the correct identification sources.

Security Parts carries the complete door closer and operator parts catalog for LCN products organized by series, with interactive diagrams. The LCN door closer parts guide covers the mechanical closer components that support COMPACT operator installations. Pre-order compatibility support is available at 845-935-0301 or sales@securityparts.com.

Conclusion

Door operators parts sourcing requires knowing the operator series, the component category responsible for the observed failure, and the four ordering specifications that LCN requires for any finish-, size-, hand-, or voltage-specific component. The AdaptivIQ controller on the Senior Swing stores learned operating parameters that are lost when the controller fails and replaced. The COMPACT Series reuses existing 4040XP mechanical closer components, making it the most serviceable retrofit operator on the market. Casting numbers on LCN components are not part numbers. The model label on the operator body and the series-specific parts page are the correct starting points for every door operators parts order. Same-day shipping on stocked components. Pre-order support at 845-935-0301.

FAQs

Are LCN door operator parts the same as LCN door closer parts? 

No. Operators include motors, controllers, actuators, and power supplies that mechanical closers do not have. The COMPACT Series reuses 4040XP mechanical closer components alongside an operator module, creating the most crossover between the two categories.

How do I find the model number on an LCN automatic door operator? 

The date of manufacture and model information are on a label on the operator body. For mechanical LCN closers, the date is stamped near the packing nut at the base of the pinion. Operators use a label rather than a stamp.

What does AdaptivIQ mean on the LCN Senior Swing?

 It is LCN's self-adjusting controller technology that continuously monitors and adjusts opening speed, hold-open time, and closing force to account for seasonal temperature changes and door condition changes without manual valve adjustment.

Why does the door make squealing sounds during automatic operation? 

Squealing or scuffing during operation typically indicates wear or misalignment in the track roller assembly or the arm connection. LCN provides specific adjustment guidance for this condition, and the track roller is a serviceable replacement component on most operator series.

Can I reuse my existing 4040XP closer if I install the COMPACT operator? 

Yes. The LCN 6400 COMPACT motor gearbox assembly connects directly to an existing 4040XP Series closer body with just four screws. Existing cylinders, including delayed action models, are compatible and remain in place.

If you manage commercial doors long enough, you end up sourcing exit devices parts more often than you plan for. A dogging assembly stripped out on a high-traffic corridor door. A center case that stopped latching cleanly on a healthcare egress opening. An end cap bracket cracked after someone propped the door open one too many times. These are not rare events. They are predictable maintenance realities on any building running Von Duprin hardware, which is most commercial buildings in North America. What separates a fast, accurate repair from a week-long wrong-part return cycle is knowing which component category you're dealing with, which part number applies to your specific series and configuration, and why the long version of the hex key matters more than most people think.

Why Exit Device Parts Are Series-Specific, Never Universal

This is the single most important fact to internalize before opening any parts catalog. Von Duprin's exit device lineup covers fourteen active series across push pad, touchbar, crossbar, and mortise configurations. Each series uses components engineered to its own dimensional and mechanical specifications. A dogging assembly from the 22 Series does not fit the 75 Series. A center case for the 98/99 rim configuration is a different part from the center case for the 98/9947 CVR configuration.

The model number stamped on the mechanism case or baseplate is the starting point for every parts order. The first two or four digits identify the series. The function suffix identifies the trim function and configuration. A "-F" suffix means fire-rated, which removes the hex dogging function entirely. Get the model number before the catalog opens.

The Six Component Categories That Cover Most Repairs

Dogging Assemblies

Dogging is the mechanism that holds the push bar in the depressed position, keeping the latch bolt retracted so the door operates freely without latching. Standard on non-fire-rated 22, 33A, 35A, 98, and 99 Series rim devices. The dogging assembly on devices made after 1997 consists of four parts that are commonly replaced individually:

• 090040 Dogging Shaft: The piece the 5/32-inch hex key inserts into. The hole depth is only approximately 1/4 inch. The long version of the hex key is mandatory. Short keys round out the hex engagement over repeated use. This is the single most common dogging failure in the field.
• 090041 Dogging Spring: Activates the dogging hook. Occasionally fails and is sold individually.
• 090042 Dogging Adapter Spring: Clips the dogging adapter into the mounting bracket.
• 090043 Dogging Adapter: The housing the shaft and spring fit through.
• 090044 Dogging Hook: Grabs the push bar mechanism and holds the dogged position on 22, 33A, 35A, 98, and 99 Series devices made after 1997.

For devices made before 1997, the old-style dogging shaft has a different dimensional profile. Part 050709 is the conversion kit that updates pre-1997 devices to current spec components.

The 88 Series crossbar devices use a 5/32-inch hex key for a different purpose: the wedgetite screw and dog screw in the lever arm assembly. This is not the same dogging operation as the push pad series, and the 88 Series dogging parts do not cross to push pad series.

Center Cases and Mechanism Cases

The center case is the primary mechanical housing of the exit device. It contains the latch mechanism, the dogging engagement, and the connection to the trim function. Center case specs differ by trim function within the same series, which is where most wrong-part orders happen.

The 22 Series rim center case (part 109012) has been in production for approximately 40 years and replaces all non-fire-rated 22 Series rim center cases with hex key dogging on the hinge-side cover plate. The 2227 SVR center case (part 109358) has been consistent for approximately 30 years. The 88 rim center case 050409 applies to EO, DT, and NL trim functions only. Lever, knob, and thumbpiece versions each use a different specification.

Push Bar and Crossbar Components

The push bar on push pad devices and the crossbar on crossbar devices absorb direct operational load on every door use. Push bar end guides (part on 33A and 98/99 devices) reduce noise and friction at the end of the push bar assembly. Crossbar tube attaching wedges (090020) and rings (090021) secure the crossbar to the device body on the 88 and 55 Series.

Push bar retrofit kits are available for 22 Series rim devices in 36-inch and 48-inch configurations, replacing the push bar assembly without requiring a full device swap.

Strikes

Strike selection depends entirely on the device configuration and fire rating status:

• 299: Standard rim strike for 22, 88, 98, and 99 Series rim devices. Also used as the top strike on 2227, 8827, 9827, and 9927 SVR devices. Measures 1-1/4 inches wide by 2-7/8 inches high, slotted hole spacing 2-1/8 inches.
• 299F: Fire-rated version for the same devices. Same dimensions. Not interchangeable with the 299 on fire-rated assemblies.
• 264: Low-profile alternative rim strike for 22, 88, 98, and 99 devices. Measures 2-7/8 inches tall by 1-1/4 inches wide, roller projection 9/16 inches.
• 304L: Standard floor-mounted SVR bottom strike for 2227, 8827, 9827, and 9927. Square flange outer dimension 1-7/8 by 1-7/8 inches.
• 248L-4: Bottom surface-mounted strike for the same SVR series. Measures 9/16 inch wide by 2-1/2 inches high, hole spacing 1-7/8 inches.
• 1609: Used on double door applications without a center post, combining one SVR leaf and one rim leaf. Not rated for fire doors.

Lever Arms and Axle Components (88 Series)

The 88 Series lever arm is replaced more frequently than any other mechanical component on crossbar devices. The cause is nearly always the same: the dogging screw strips out due to the wedgetite screw seating incorrectly. The right-hand lever arm kit is part 050438. The left-hand kit is 050439. Each includes the wedge, wedge ring, wedgetite screw, and dog screw.

Top Latch and SVR Latch Components

For SVR configurations, top latch bracket replacement kits (050091 for 22/98/9927 Series) replace worn top latch assemblies. The 8827 bottom latch case (050461) covers all non-fire-rated 8827 SVR devices. Latch covers 050464 cover the top and bottom latches on the 8827 and the bottom latch only on the 8827-F fire-rated version.

Electrified Upgrade Parts

Three electrified upgrade kits appear most often in parts orders on commercial facilities:

QEL Modular Conversion Kit (114317-00): Adds quiet electric latch retraction to a mechanical 22, 33A, 35A, or 98/99 Series device. Field-installable without opening the device body on current-generation hardware.

ALK Alarm Kit: Converts the 22, 33A, 35A, 98, or 99 Series to an alarmed exit device. Powered by a standard 9-volt battery. Controlled by a mortise cylinder (sold separately).

QEL Baseplate Conversion Kits: The QELA baseplate conversion kits (040063 for 36-inch devices, 040068 for 48-inch devices) are required on some older devices when adding QEL. The HD-QELA versions (040064 and 040068) cover heavy-duty applications.

How to Source Exit Device Parts Without a Wrong-Part Return

Most wrong-part orders on exit device parts come from searching by component name rather than by model. A dogging assembly listed under "Von Duprin dogging assembly" without a series designation could apply to a pre-1997 device, a post-1997 push pad device, or a crossbar device. The correct part depends on the series and generation.

Security Parts organizes the complete Von Duprin exit devices catalog by series and model. Every model page carries an interactive parts diagram showing the full assembly. Navigate to the correct series, open the diagram, confirm the component visually against the physical device, and place the order from the model-specific parts list. The 98/99 Series, 22 Series, and 88 Series each have their own dedicated pages with complete parts breakdowns.

Same-day shipping on stocked components. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

Exit device parts sourcing is a model-first process, not a category search. The series, the configuration (rim vs SVR vs CVR vs mortise), the manufacturing year (pre-1997 vs post-1997 for dogging assemblies), and the trim function all determine which specific component applies to the device on the door. The dogging shaft 090040 requires the long hex key. The center case specification depends on the trim function, not just the series. The 1609 strike is not rated for fire doors. Starting with the model number before opening the exit devices parts catalog is what makes the first order the right order.

FAQs

Are exit device parts interchangeable between Von Duprin series?

 No. Parts are series-specific and often configuration-specific within the same series. A 22 Series center case does not fit a 75 Series device. Always confirm the model number before ordering.

What hex key size is used for Von Duprin dogging? 

5/32-inch hex key for push pad devices (22, 33A, 35A, 98, 99 Series). The dogging hole is only 1/4 inch deep, so the long version is required. Short keys round out the shaft engagement over time.

What is the difference between the 299 and 299F strike? 

The 299 is the standard rim strike for non-fire-rated devices. The 299F is the fire-rated version. Same dimensions, not interchangeable. The 299F carries the UL fire door listing required on fire-rated assemblies.

What causes an 88 Series lever arm to need replacement? 

The most common cause is the dogging screw stripping out when the wedgetite screw is not seated correctly. The lever arm kit includes the wedge, wedge ring, wedgetite screw, and dog screw.

What is the QEL modular conversion kit?

 Part 114317-00 adds quiet electric latch retraction to an existing mechanical Von Duprin device, allowing electronic outside entry without a full device replacement. Compatible with 22, 33A, 35A, and 98/99 Series.

Panic hardware for commercial doors is a code-defined life safety system with specific occupancy triggers, installation dimensions, fire rating distinctions, and device type requirements that vary by building use and adopted code. The model codes define it precisely: a door-latching assembly that releases the latch upon the application of a force in the direction of egress travel. The Iroquois Theatre fire on December 30, 1903 in Chicago killed 596 people, many unable to exit through doors requiring deliberate unlocking under pressure. That event directly produced the first panic release device, developed by Carl Prinzler and Henry DuPrin. Building codes adopted panic hardware requirements in the decades following, and today the requirement is embedded in both the International Building Code and NFPA 101. Getting the specification right requires understanding three things: when code mandates it, which device type fits the door, and what separates standard panic hardware from fire exit hardware.

When Is Panic Hardware Required: IBC vs NFPA 101

This distinction causes more specification errors than any other in commercial door hardware. Panic hardware is not required on every commercial door. It is triggered by occupancy type and calculated occupant load.

Under the International Building Code (IBC), panic hardware is required on egress doors equipped with a lock or latch serving:

• Assembly occupancies (Group A): 50 or more people
• Educational occupancies (Group E): 50 or more people
• High-hazard occupancies (Group H): regardless of occupant load

Under NFPA 101 Life Safety Code, the threshold is different:

• Assembly, educational, and day care occupancies: 100 or more people
• High-hazard occupancies: more than 5 people

The IBC uses 50 people. NFPA 101 uses 100. The authority having jurisdiction (AHJ) determines which code applies in a given location. Many US jurisdictions follow the IBC. Others adopt NFPA 101. Some adopt both with local amendments. Always confirm which code version is in force before making any panic hardware determination.

The means of egress extends beyond the immediate room exit door. The IBC defines it as a continuous and unobstructed path of vertical and horizontal egress travel from any occupied portion of a building to a public way, consisting of the exit access, the exit, and the exit discharge. All doors in that path that are equipped with a lock or latch and serve the qualifying occupancy and occupant load must carry panic hardware.

Standard Panic Hardware vs Fire Exit Hardware

This is the distinction most commonly misapplied in the field. Not all panic hardware is appropriate for fire-rated doors.

Standard panic hardware is tested and listed for panic exit applications. It can include mechanical dogging, which holds the push bar in the depressed position so the door operates as a push/pull entry without latching. Mechanical dogging is acceptable on non-fire-rated egress doors.

Fire exit hardware is tested and listed for both panic exit and fire door applications. The defining requirement is positive latching: the device must latch automatically every time the door closes. Mechanical dogging is not permitted on fire exit hardware because a dogged-open fire door cannot provide the compartmentalization that the fire door assembly requires. Fire-rated Von Duprin configurations carry the "-F" suffix in the model number (98-F, 22-F, 88-F). These devices have no hex dogging function.

For applications where a fire door needs to be held open operationally, electric latch retraction (QEL or ELR) tied to the fire alarm is the acceptable solution. When the fire alarm activates, the electric dogging releases and the door latches automatically.

The Four Device Types and When Each Applies

Rim devices are the most common panic hardware in commercial construction. The closer body and latch bolt mount on the door face. The entire mechanism is visible, surface-mounted, and directly accessible for maintenance. Fits single doors and paired doors with a center mullion. Available on the Von Duprin 22, 75, 88, 98/99, and 33/35A Series.

Surface vertical rod (SVR) devices add top and bottom engagement points via surface-mounted rods running vertically on the door face. Used on double door openings without a center mullion where rim device single-point engagement is insufficient. The 2227, 8827, and 9827/9927 configurations cover this application across Von Duprin series.

Concealed vertical rod (CVR) devices provide the same three-point engagement as SVR but route the rod hardware inside the door. Specified when surface-mounted rods are architecturally unacceptable: hotels, healthcare interiors, high-end commercial spaces. More installation-intensive and more costly to maintain.

Mortise devices integrate a full mortise lock body into the panic hardware chassis. The latch bolt is housed inside a mortise pocket cut into the door edge, providing maximum security depth alongside panic egress. The Von Duprin 98/9975 and 8875 configurations use the 7500 mortise lock body, which has been in service since approximately 1977 and measures 5-7/8 inches high by 4-1/2 inches deep by 1 inch thick.

Installation Requirements

Regardless of device type, the model codes and OSHA specify:

• Mounted between 34 and 48 inches above the finished floor or threshold
• Push bar must span at least half the door width
• Single-motion operation: one push releases the latch, no secondary action required
• No secondary locking device (chain, padlock) that would prevent operation

ADA requirements add a maximum 5-pound opening force for interior doors on accessible egress routes and single-motion operability without tight grasping, pinching, or twisting.

Electrified Options for Access Control Integration

The 98/99, 22, 33/35A, and 75 Series all support electrified integration at the device level:

• QEL (Quiet Electric Latch Retraction): Modular field-installable conversion that retracts the latch on an authorized signal, silently
• MEL (Motorized Electric Latch Retraction): Motor-driven retraction for applications where solenoid noise is unacceptable
• Chexit Delayed Egress: Holds the door latched for 15 seconds after push bar activation, with a local alarm during the delay
• ALK (Alarm Exit Kit): Converts the device to an alarmed exit; powered by a 9-volt battery, controlled by a mortise cylinder
• RX (Request to Exit): Switch in the push bar signals the access control system when the bar is pressed

Selection Decision Framework

Conclusion

Selecting the correct panic hardware for commercial doors requires resolving four decisions in sequence: which code applies in the jurisdiction, what the calculated occupant load of the space is, whether the door is fire-rated (which determines the standard panic hardware vs fire exit hardware distinction), and which device type fits the door configuration. Security Parts organizes the complete Von Duprin panic hardware catalog by series with model-specific parts pages, interactive diagrams, and same-day shipping on stocked components. Pre-order support at 845-935-0301 or sales@securityparts.com for specification questions before the order is placed.

FAQs

When is panic hardware required under the IBC?

 Assembly (Group A) and educational (Group E) occupancies with a calculated occupant load of 50 or more people, and high-hazard occupancies (Group H) regardless of occupant load, when egress doors are equipped with a lock or latch.

What is the difference between panic hardware and fire exit hardware? 

Standard panic hardware can include mechanical dogging and is listed for panic applications. Fire exit hardware is listed for both panic and fire door applications, must positively latch every time, and has no mechanical dogging. On Von Duprin devices, the "-F" suffix designates fire exit hardware.

Does the IBC or NFPA 101 set the higher occupant load threshold?

 NFPA 101 sets the higher threshold at 100 people. The IBC sets it at 50. The authority having jurisdiction determines which code applies in a specific project location.

Can a fire door be held open if it has panic hardware? 

Not with mechanical dogging. Electric dogging (QEL, ELR) connected to the fire alarm is the accepted method. The door latches automatically when the fire alarm activates.

What is the ADA opening force requirement for panic hardware on accessible routes? 

Maximum 5 pounds for interior non-fire-rated doors. Single-motion operation without tight grasping, pinching, or twisting is required.

The Von Duprin 22 Series parts and applications catalog covers a practical, cost-effective Grade 1 panic exit device built for mid-traffic commercial openings where the full institutional specification depth of the 98/99 Series is not required but code-compliant panic egress is. Employee entrances, parking garage stairwells, healthcare clinics, multi-family residential corridors, and back-of-house retail doors. The 22 Series carries ANSI/BHMA A156.3 Grade 1 certification (2014 edition), UL listing for both panic exit hardware and fire exit hardware, and a parts catalog that has remained largely consistent for decades, which means components ordered today apply correctly to 22 Series devices installed in the early 1990s.

What the 22 Series Is Built For

Von Duprin developed the 22 Series as the value-tier Grade 1 exit device in its lineup. The designation "22" reflects its position in the Von Duprin family below the institutional 98/99 and above residential-grade hardware. It is the most widely installed panic device in mid-traffic commercial and multi-family applications across the US.

The device ships non-handed, meaning it can be installed on left-hand or right-hand swing doors without modification. It fits door stiles as narrow as 3-13/16 inches on standard non-fire-rated configurations and 4-3/8 inches on fire-rated configurations. Compatible door thicknesses are 1-3/4 inches and 2-1/4 inches for both wood and metal doors. Available in 36-inch (3') and 48-inch (4') lengths to suit standard commercial door widths.

The center case measures 4-1/4 inches by 1-3/8 inches by 2-3/8 inches (108 x 41 x 60 mm). The mechanism case measures 2 inches by 3-3/4 inches (51 x 95 mm). Push bar projection is 3-3/4 inches (95 mm) at neutral and 3 inches (76 mm) when depressed. The touchbar height is 39-13/16 inches (1011 mm) standard, and 39-11/16 inches (1008 mm) when used with a mullion.

Configurations: Rim and Surface Vertical Rod

22 Rim Device

The rim configuration is the standard 22 Series device for single doors and paired doors with a center mullion. The latch bolt projects from the device body on the door face and engages the 299 rim strike mounted on the door frame. The device ships with the 299 strike in dull black finish, a 5/32-inch hex dogging key, and all mounting fasteners for both 1-3/4 inch and 2-1/4 inch door thicknesses. Optional sex nuts and bolts (SNB) are available for through-bolt mounting.

The device covers stock hollow metal doors with 161 door prep cutouts.

2227 Surface Vertical Rod Device

The 2227 is the surface vertical rod configuration of the 22 Series, used on double door openings without a center mullion. The top rod engages a strike at the door header, the bottom rod engages the floor or threshold, providing three-point engagement. The 2227 uses a separate center case (part 109358) from the rim device (part 109012). These cases are not interchangeable, and confirming the configuration before ordering a center case kit is the step that prevents the most common wrong-part order on 22 Series maintenance.

Trim Functions and Outside Hardware

The 22 Series ships ready for multiple outside trim functions. Understanding the function suffix is what determines which outside trim component applies to the opening:

• EO (Exit Only): No outside trim. The push bar operates egress from inside only. No outside entry function.
• DT (Dummy Trim): Outside pull only, no locking function. Used on non-secured egress doors where an outside handle is needed for aesthetics.
• NL (Night Latch): Key locks and unlocks the push bar from outside. The 230NL trim plate measures 3 inches wide by 12-1/16 inches high by 3/32 inches thick.
• TP (Thumbpiece): Outside thumbpiece unlocks the push bar. Used where key access is not required but outside entry control is needed.
• K (Knob): Outside knob trim. Economy application.
• L (Lever): Outside lever trim. The 230L trim was redesigned in 2008, moving the cylinder from inside the lever to a position above the lever. Current 230L dimensions: 3 inches wide by 6-3/8 inches high, 15/16 inches thick.

The 230 Series is the full-size trim line for the 22 and 2227 devices. The 210 Series is the economy trim line. The 230L and 210L levers use a shear pin (3/16-inch diameter by 5/8-inch overall length) at the lever base, designed to break if the lever is forced. This protects the trim assembly from damage on high-abuse applications. Shear pins are stocked as individual replacement components.

The 22 Series Parts That Require Most Replacement

Center Cases

The 22 Rim center case part 109012 has been in production for approximately 40 years. It replaces all non-fire-rated 22 Series rim center cases, which means any 22EO device with hex key dogging on the hinge-side cover plate uses this case. This backward compatibility is valuable for facilities maintaining 22 Series devices installed in the 1980s and 1990s.

The 2227 SVR center case part 109358 has been consistent for approximately 30 years and replaces all worn 2227 SVR center cases.

Dogging Assembly

Hex key dogging is standard on all non-fire-rated 22 Series rim devices. The dogging assembly consists of three components that are commonly ordered individually or as a kit:

• 090040 Dogging Shaft: The piece the 5/32-inch hex key inserts into. Critical installation note: the hole depth is only approximately 1/4 inch. The long version of the 5/32-inch hex key must be used. Short keys do not reach the full depth of the shaft and round out the hex over time, which is the most common cause of dogging failure on 22 Series devices in the field.
• 090042 Dogging Adapter Spring: Locks the dogging adapter into the mounting bracket.
• 090043 Dogging Adapter: The housing the shaft and spring fit through.

For 22 Series devices manufactured before 1998, the old-style dogging shaft has a different dimensional profile. Part 050709 is the conversion kit that updates pre-1998 devices to current spec dogging components.

End Cap and Bracket

The plastic end cap on the hinge side of the 22 Series device is historically the component most likely to fail on high-use applications. When the end cap breaks, the dogging cover plate slides off and the device loses weather and debris protection. In 2016, Von Duprin introduced the 900397 metal end cap kit, replacing the plastic end cap with a metal version. This kit includes the end cap, bracket, and mounting screws. The full end cap and bracket assembly 900981 is the replacement for broken plastic end cap and bracket combinations. As of October 2014, Von Duprin no longer sells the plastic cap only; the complete assembly ships in its place.

Push Bar Retrofit Kits

Push bar retrofit kits are available for 22 Series rim devices in both 3-foot (36-inch) and 4-foot (48-inch) configurations. These kits replace the push bar assembly without requiring a full device swap, which is the correct maintenance approach when the push bar itself is bent or damaged but the mechanism case is functional.

Finishes

22 Series devices and trim are available in: powder-coated aluminum (689), powder-coated dark bronze (695), powder-coated chrome (526), powder-coated matte black (622), SP28, and SP313. Finish must be specified when ordering most trim components.

Electrified Options for the 22 Series

The 22 Series was designed for mid-traffic openings, but its electrified options catalog supports meaningful access control integration:

RX (Request to Exit): A switch placed in the push bar sends a signal to the access control panel when the push bar is depressed. This monitors egress activity on the opening without controlling it.

LX (Latch Monitor Switch): Monitors the position of the latch bolt itself, signaling when the door is not properly latched.

RX2 (Double Pushpad Monitor): Covers both push bar and pushpad monitoring in a single device.

QEL (Quiet Electric Latch Retraction): A modular field-installable conversion that adds electric latch retraction to a mechanical 22 Series device. When an authorized credential is presented or a remote release signal is received, the latch retracts silently, allowing entry from the outside without a key.

ALK (Alarm Exit Kit): Converts the 22 Series device to an alarmed exit device. Powered by a standard 9-volt battery. Controlled by a mortise cylinder (not included with the kit). When the push bar is depressed, the alarm sounds.

CON (Allegion Connect): Integrates the device into the Allegion wireless ecosystem for remote monitoring and control.

The QM SVR Device Retrofit Kit is available for 2227 configurations, converting older surface vertical rod devices to current-generation specifications without a full device replacement.

Why Security Parts Is the Right Source for 22 Series Components

The 22 Series parts catalog is both consistent and generationally stable. This works in both directions. The center case part 109012 applies to a 22 Series device installed today and to one installed in 1985. The dogging assembly components 090040, 090042, and 090043 apply to devices manufactured after 1998 across the 22, 33A, 35A, 98, and 99 Series. That consistency means a technician can confirm compatibility by confirming the series and the manufacturing year rather than hunting for a discontinued part number.

Security Parts organizes the complete Von Duprin 22 Series parts and applications catalog by model, with interactive parts diagrams for the 22 rim device and the 2227 SVR device. The diagram on each model page shows every component in the assembly, allowing visual confirmation of the part before the order is placed. This is the step that prevents the 109012 rim center case from being ordered for a 2227 SVR device that requires the 109358.

For the full Von Duprin lineup beyond the 22 Series, the Von Duprin brand catalog and exit devices section cover every active series with the same model-specific parts organization. Same-day shipping on stocked components from US warehouses. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

The Von Duprin 22 Series delivers Grade 1 panic exit performance for the broad middle tier of commercial, healthcare, multi-family, and retail applications where the full institutional specification of the 98/99 Series is not required. The rim and 2227 SVR configurations cover the full range of single and paired door openings. Center cases have been consistent for decades. The dogging shaft 090040 requires the long version of the 5/32-inch hex key. The metal end cap kit 900397 resolves the historically weak plastic end cap. And the electrified options catalog, from RX monitoring through QEL modular conversion, supports meaningful access control integration on any 22 Series opening. Sourcing replacement parts starts with confirming the configuration (rim vs SVR) and the manufacturing year, then navigating to the correct model page in the Von Duprin 22 Series parts and applications catalog at Security Parts where diagrams confirm every component before the order is placed.

FAQs

What applications is the Von Duprin 22 Series designed for?

 Employee entrances, parking garage stairwells, healthcare clinics, multi-family residential corridors, and retail back-of-house doors. It is the mid-traffic Grade 1 specification in the Von Duprin lineup, below the institutional 98/99 Series in specification depth.

What is the difference between the 22 rim and 2227 SVR configurations? 

The 22 rim device latches at a single frame-side strike and is used on single doors or paired doors with a center mullion. The 2227 SVR device uses top and bottom rods for three-point engagement on double door openings without a center post.

Are 22 Series center cases interchangeable with 2227 SVR center cases? 

No. The 22 rim center case is part 109012. The 2227 SVR center case is part 109358. These are different components and cannot be swapped between configurations.

Why does the 22 Series dogging key stop working over time? 

The dogging shaft hole (part 090040) is approximately 1/4 inch deep. Using a short 5/32-inch hex key that does not reach full depth rounds out the hex engagement over repeated use. Always use the long version of the 5/32-inch key, pressing the key fully into the shaft before turning.

Does the Von Duprin 22 Series support electrified access control?

 Yes. QEL modular conversion adds quiet electric latch retraction. RX and LX options add monitoring switches. The ALK alarm kit converts the device to an alarmed exit. CON integrates the device into the Allegion Connect ecosystem.

What is the metal end cap kit for the 22 Series?

 Von Duprin introduced the 900397 metal end cap kit in 2016, replacing the historically fragile plastic end cap with a metal version. The kit includes the end cap, bracket, and mounting screws. As of October 2014, the plastic cap alone is no longer sold separately.

Commercial door closers are not interchangeable. The surface-mounted closer on an office interior door is a different device category from the overhead concealed closer on an architectural lobby entry, which is again different from the floor spring closer on a heavy all-glass storefront. ADA lawsuits related to door closer violations have increased in recent years, and the fire door inspection failure most commonly cited in commercial facilities involves a closer that is either the wrong ANSI grade for the assembly or incorrectly adjusted. Specifying or replacing the wrong type does not just create a maintenance problem. It creates a compliance liability. This guide covers every commercial door closer type, how ANSI/BHMA grades work, how the four hydraulic valve functions control the closing cycle, and how to match the right closer to the right application.

The Four Main Types of Commercial Door Closers

Surface-Mounted Closers

Surface-mounted closers are the most common commercial installation. The closer body mounts to the face of the door or frame and is visible after installation. The mechanism inside most surface closers uses a rack-and-pinion system: a piston riding on a rack turns a pinion shaft connected to the spring. When the door opens, the spring compresses and stores energy. When released, hydraulic fluid controls how fast the spring drives the door closed.

Four arm configurations are available:

• Regular arm (pull side): Closer body on the pull side of the door, arm extends to the frame. Most common interior door setup. Strongest closing force, most visible projection.
• Parallel arm (push side): Closer body on the push side of the door, arm runs parallel to the frame when the door is closed. Lowest projection from the door face. Protects the arm from deliberate force. Standard on exterior commercial doors.
• Top jamb (push side frame): Closer body mounts on the frame head on the push side, arm connects to the door. Correct when the pull side is inaccessible or when the closer must mount on the frame. Common on aluminum storefront and narrow-top-rail glass doors.
• Slide track arm: The arm rides in a metal track on the frame rather than a fixed pivot, allowing the door to hold open at any position. Used in hospital corridors, loading docks, and any application requiring variable hold-open.

The most common arm geometry error in the field: the shoe mounted too far from the hinge side creates excessive stress on the arm pivot. Too close reduces mechanical advantage. The shoe must be set at the position specified in the manufacturer's template for the closer to perform correctly and last through its rated cycle life.

LCN has manufactured commercial door closers since 1877. The 1460 Series is the universal medium-duty closer for commercial and institutional applications, meeting ANSI/BHMA A156.4 Grade 1 and ADA requirements, with a 30-year limited warranty. The LCN patented Green Dial system on the 1460 removes the guesswork from spring power adjustment. The 4040XP is the heavy-duty specification for institutional and industrial openings.

Overhead Concealed Closers

Overhead concealed closers mount inside the door frame transom or the top rail of the door, hiding the mechanism when the door is closed. These are specified on aesthetic-driven applications: hotel lobbies, healthcare interiors, high-end office buildings, and government facilities where surface hardware is architecturally unacceptable.

Installation requires greater precision than surface-mounted closers because the frame transom must accommodate the closer body and the door rail must accept the arm channel.

LCN's 3030/3130 Series is the Grade 1 overhead concealed closer for interior doors in medium to high-traffic applications. The 3030 uses an exposed double-lever arm. The 3130 uses a concealed single-lever arm with a low-friction track and roller assembly. Both carry ANSI/BHMA A156.4 Grade 1 rating and a 15-year limited warranty.

For institutional and high-traffic installations or those exposed to weather or abuse, the 2010/5010 Series provides heavy-duty concealed performance. The 2010 conceals both the body in the frame and the track in the door. The 5010 conceals the body in the frame with an exposed double-lever arm.

The 2210 Series is LCN's high-security concealed closer for correctional facilities and institutional buildings requiring vandalism resistance. It uses forged steel, a single-lever arm, a heavy steel mounting plate, and tamper-resistant components.

Floor Spring Closers

Floor spring closers embed in a cement case in the floor beneath the door, placing the pivot mechanism at the door base rather than at the top. They are specified for heavy glass doors, balanced doors, all-glass rail and patch-fitted entries, and applications where no visible closer hardware is acceptable on the door or frame.

Some floor spring models support doors up to 300 pounds. They are the most durable and longest-lasting closer type for very heavy-traffic applications because the mechanism is protected inside the floor. The primary drawback is that installation requires cutting into the floor slab, making floor springs impractical for retrofits in most existing buildings.

Automatic Door Operators

Automatic operators use an electric motor triggered by a push pad, motion sensor, or access control signal. They are required under NFPA 101 in healthcare patient care areas, in assembly occupancies where conventional closers cannot achieve ADA compliance due to door weight and wind load, and in any touchless entry application.

ANSI/BHMA A156.4 Grades and Hydraulic Systems

Grade 1: Rated for 2 million cycles. Required on all fire-rated door assemblies and high-traffic commercial openings. Grade 1 closers must also carry a UL fire door listing for use on fire-rated assemblies. At 500 cycles per day, a Grade 1 unit provides approximately 11 years of rated cycle life.

Grade 2: Rated for 1 million cycles. Suitable for moderate-traffic interior doors where no fire rating is required.

Grade 3: Rated for 500,000 cycles. Not appropriate for commercial applications with a fire door requirement. At the same 500 cycles per day, a Grade 3 unit reaches mechanical fatigue in under 3 years.

Most commercial closers combine a hydraulic system with a mechanical spring. Standard hydraulic fluid performs reliably in typical interior conditions. All-weather hydraulic fluid maintains consistent viscosity from -40 degrees Celsius to 80 degrees Celsius and is required on exterior doors, vestibule applications, and any installation exposed to temperature extremes. As temperature rises and standard hydraulic fluid thins, the closer may fail to latch. All-weather fluid prevents this.

The Four Hydraulic Valve Functions

Every hydraulic commercial closer has four adjustment valves. Understanding each prevents the most common installation errors.

Sweep speed: Controls door movement from fully open to approximately 12 to 15 degrees from closed. This is the longest phase of the arc and the one most responsible for slamming.

Latch speed: Controls the final degrees from 12 to 15 degrees to fully latched. Must be fast enough to engage the latch bolt positively. On fire doors, this latching is the code requirement.

Backcheck: Controls the hydraulic resistance against forceful opening beyond approximately 70 to 80 degrees, protecting hinges, frame, and wall from impact.

Delayed action: When present, holds the door open at approximately 70 degrees for an adjustable delay before the closing cycle begins. Used in healthcare and any application where equipment must clear the door frame.

Every closer should be adjusted in the field after mounting based on actual door weight, wind exposure, and latch requirements. Factory default settings rarely match field conditions.

ADA Compliance Requirements

The Americans with Disabilities Act requires:

• Maximum 5 pounds of opening force for interior non-fire-rated doors
• Minimum 5 seconds from 90 degrees open to 12 degrees open for closing speed
• California state ADA requires the 5-pound limit on both interior and exterior doors

A closer adjusted for fast latching on a busy corridor will typically fail the 5-second measurement. On accessible egress routes, the sweep speed valve must be set for the full 5-second minimum. Where door weight and wind load make the 5-pound opening force limit physically unachievable with a conventional closer, an automatic operator or balanced door system is the correct solution.

Selection Decision Table

Sourcing Parts for the Closer Already on Your Door

Every closer type and series in this guide has its own parts tree. The model number on an LCN closer is located under the cover on a sticker on the cylinder body. On mechanical closers, the manufacturing date is stamped near the packing nut at the base of the pinion shaft. This number determines which arm, which drop plate, and which cover plate applies to that specific device.

Security Parts organizes the complete door closer parts catalog by model across LCN 1000 Series, 4000 Series, and 3030/3130 concealed closers. The LCN door closer parts guide covers specific component categories with interactive diagrams on every model page. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

Commercial door closer selection follows a clear sequence: fire rating requirement first, then aesthetics, then traffic level, then frame geometry and door material. ANSI/BHMA A156.4 Grade 1 with a UL fire listing is non-negotiable on rated fire door assemblies. Surface-mounted closers are the practical standard for most commercial applications. Overhead concealed closers address aesthetic requirements without sacrificing Grade 1 performance. Floor springs handle the heaviest glass and balanced door applications. The four hydraulic valve functions control operational quality and must be adjusted in the field. All-weather fluid is required for exterior and temperature-exposed installations. Sourcing replacement parts starts with the model number under the closer cover, not with a component name or brand search. Browse the complete commercial door closers catalog at Security Parts with model-specific diagrams and same-day shipping.

FAQs

What are the ANSI/BHMA grades for commercial door closers? 

Grade 1 is rated for 2 million cycles, required on fire-rated assemblies and high-traffic commercial openings. Grade 2 covers 1 million cycles for moderate-traffic interior doors without fire ratings. Grade 3 covers 500,000 cycles and is not appropriate for commercial fire door applications.

What is the ADA opening force requirement for commercial door closers? 

Maximum 5 pounds for interior non-fire-rated doors. Minimum 5 seconds from 90 degrees to 12 degrees for closing speed. California requires the 5-pound limit for both interior and exterior doors under state code.

What is the difference between standard and all-weather hydraulic fluid in door closers?

 Standard hydraulic fluid works in controlled interior environments. All-weather hydraulic fluid maintains consistent viscosity from -40 to 80 degrees Celsius. Required for exterior doors and any installation exposed to temperature extremes where standard fluid would thin and fail to latch the door.

When is a floor spring closer the correct specification? 

Heavy glass doors, all-glass rail and patch-fitted entries, and balanced doors where no surface mounting location is available. Some models support doors up to 300 pounds. Installation requires cutting into the floor slab, making them impractical for most retrofit applications.

What are the four hydraulic valves on a commercial door closer?

 Sweep speed controls the main arc from open to near-closed. Latch speed controls the final degrees before latching. Backcheck controls resistance against forceful opening. Delayed action holds the door open briefly before the closing cycle begins.

Can any Grade 1 door closer be used on a fire-rated door assembly?

 No. The closer must be both Grade 1 rated and UL listed for fire door assemblies. Closers with mechanical hold-open features that do not include a fire alarm release are not acceptable on fire-rated doors.

Most facility managers know what a rim exit device is. Far fewer know the exact NFPA 80 documentation requirement, which failure signs require same-day action, why oil-based lubricants accelerate failure, or what happens when the wrong replacement part gets ordered because the model number was not confirmed first. This guide covers all four. It is written for the facility manager responsible for keeping egress hardware compliant, functional, and documented across a commercial building.

What Makes Rim Exit Devices the Most Commonly Maintained Egress Hardware

A rim exit device is surface-mounted on the face of the door. The latch bolt projects from the device body itself, engages a strike plate on the frame, and the entire mechanism is visible, accessible, and exposed to daily operational conditions. That visibility is an operational advantage: problems are observable before they become failures. A stiff push bar, a latch that fails to retract cleanly, or a dogging mechanism that no longer holds are all diagnosable without disassembly.

ANSI A156.3 Grade 1 certified devices, which covers the Von Duprin 98/99, 22, and 75 Series running on the majority of commercial doors, are rated for 2 million operation cycles. That rating assumes correct installation, appropriate lubrication, and fastener integrity maintained over the device's service life. A consistent three-tier inspection schedule is what keeps the device performing to that standard.

The Three-Tier Inspection Schedule

Monthly Visual Checklist

Monthly inspections take under two minutes per door. The purpose is catching developing problems. A push bar showing early stiffness is a lubrication job. A push bar that is binding and failing to latch consistently is a code compliance issue. Catching the difference monthly prevents the second from appearing on an inspection report.

Quarterly: Fasteners and Lubrication

Every quarter, check and tighten all mounting fasteners on the device body, baseplate, and strike plate. Loose fasteners create play in the installation that accelerates wear on every internal component. Do not over-torque: fastener specifications are in the Von Duprin installation instructions for each series and are application-specific across wood door, hollow metal door, and metal frame installations.

Lubrication is the most frequently mishandled maintenance step on rim exit devices. Use a dry lubricant, typically a graphite or PTFE-based product, on the latch bolt, the dogging shaft, and the push bar pivot points. Do not use oil-based lubricants. Oil attracts dust and debris, which forms a paste in the mechanism over time and produces the binding behavior it was applied to prevent. On the Von Duprin 98/99 and 22 Series, the dogging shaft (part 090040) and the dogging hook (part 090044) are the highest-turnover components on high-cycle openings, and they benefit most from consistent dry lubrication.

Annual: NFPA 80 Inspection

For fire-rated doors, NFPA 80 Section 5.2 (2022 edition) requires an annual inspection of the complete fire door assembly by a qualified person. For the exit device specifically, the annual inspection must verify:

• The device is the correct UL-listed unit for the fire door assembly
• The device positively latches without manual assistance every time the door closes
• No field modifications have been made to the device or strike that would void the UL listing
• The door closer is present and operational (NFPA 101 Life Safety Code requires a closer on every fire door to prevent smoke and flame spread)
• No evidence of dogging on a fire-rated device (fire-rated devices carry the "-F" suffix in the model number and have no dogging function by design)

IBC Section 1010.2.8 covers panic hardware requirements in the means of egress. For assembly and educational occupancies with a calculated occupant load of 50 or more, doors equipped with a latch or lock must carry panic hardware across the entire means of egress path, not just the immediate room exit.

Documentation requirement: NFPA 80 requires written records of the annual inspection including the date, the inspector's name, a description of hardware inspected, and any deficiencies found and corrected. Most jurisdictions require these records retained for a minimum of three years and available to the authority having jurisdiction (AHJ) on request.

Six Failure Signs That Require Immediate Action

These conditions require action when observed, regardless of when the last scheduled inspection occurred:

Door fails to latch when released. On a fire-rated door, this is an immediate NFPA 80 violation. Caused by a worn latch return spring (090039), a damaged center case, or a deformed latch bolt.

Push bar does not return to the extended position. Indicates a failed internal spring or a stuck dogging assembly. The door will not latch after the next operation cycle.

Visible gap between latch bolt and strike plate. The 299 rim strike on Von Duprin 98/99 and 22 Series devices measures 1-1/4 inches wide by 2-7/8 inches high with 2-1/8-inch slotted hole spacing. A gap indicates strike shift or door sag.

Grinding or clicking during operation. Lubrication resolves noise temporarily. Persistent noise after dry lubrication indicates internal component wear requiring part replacement, not repeat lubrication.

Physical impact damage. A bent push bar, cracked casting at any pivot point, or body deformation compromises structural integrity and voids the 2 million cycle performance assumption.

Unauthorized modification. Wedges propping the door open, zip ties holding the push bar depressed, or any field modification to the device or strike voids the UL listing on a fire-rated assembly. Requires immediate correction and documentation.

ADA Compliance on Accessible Egress Routes

The ADA sets a maximum opening force of 5 pounds for interior doors on accessible egress routes. Exit devices must be mounted between 34 and 48 inches above the finished floor. Single-motion operation with no tight grasping, pinching, or twisting is required.

Where ADA compliance problems surface most often in practice: the door closer, not the exit device. A closer set to too high a closing force makes an otherwise-compliant device functionally non-compliant. Annual inspection of the device on an accessible route must include an opening force measurement at the closer, not just an inspection of the device itself.

Ordering Replacement Parts: Model Number First, Always

The model number stamped on the mechanism case or baseplate is the sourcing key. It encodes the series, configuration, and trim function, all of which determine which replacement components apply. A center case kit for the 98/99 rim configuration is a different part from the center case kit for the 98/9947 CVR device. The 299 rim strike is not the same as the 299F fire-rated strike.

Security Parts organizes the complete Von Duprin parts catalog by series and model with interactive diagrams on every model page. Navigate to the specific series, including the 98/99 Series, 22 Series, and 88 Series, use the diagram to confirm the failing component visually, and place the order with the correct part number for that specific model. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

Rim exit devices are the most common and most maintained egress hardware in commercial facilities. Monthly visual checks catch developing problems early. Quarterly fastener tightening and dry lubrication prevent the premature component wear that shortens device service life. Annual NFPA 80 inspections cover fire-rated assemblies with documentation retained for three years. The six failure conditions require immediate action when observed. ADA compliance extends to the door closer, not just the device. And every replacement parts order starts with the model number on the mechanism case before the catalog opens. Running this schedule consistently is what keeps rim exit devices compliant, functional, and documented across the full service life of the hardware.

FAQs

How often should rim exit devices be inspected? 

Monthly visual checks for basic function and damage. Quarterly fastener tightening and dry lubrication. Annual NFPA 80 inspection for fire-rated door assemblies with written documentation retained for three years.

What does NFPA 80 require for rim exit device annual inspections? 

NFPA 80 Section 5.2 (2022 edition) requires annual inspection by a qualified person, covering the full fire door assembly including the device, closer, door, frame, and hardware, with written documentation of all findings.

What lubricant should I use on a rim exit device?

 Dry lubricant only, graphite-based or PTFE-based. Oil-based lubricants attract dust, form a paste in the mechanism over time, and cause the binding behavior they were applied to prevent.

Can a fire-rated rim exit device be dogged open?

 No. Fire-rated devices (identified by the "-F" suffix in the model number) have no dogging function. Dogging a fire door open violates the NFPA 80 fire door assembly listing and the UL certification of the device.

What is the ADA opening force requirement for rim exit devices? 

Maximum 5 pounds for interior doors on accessible egress routes. Mounted between 34 and 48 inches above the finished floor. Single-motion operation with no tight grasping, pinching, or twisting required.

What causes a rim exit device push bar to stop returning to the extended position?

 A failed latch return spring (090039), a damaged mechanism case, or a stuck dogging assembly. This condition prevents the door from latching after the next operation cycle and requires inspection and part replacement.

The Von Duprin panic bar lineup covers fourteen active series across push pad, touchbar, crossbar, and mortise configurations for single doors, paired doors, aluminum storefronts, correctional facilities, and every commercial application in between. Specifying the wrong series is not a cosmetic mistake. It produces a device that physically does not fit the door, fails code compliance on a fire-rated assembly, or creates an access control integration problem that does not surface until the opening is commissioned. This guide matches every active Von Duprin series to the application it was engineered for, with the specific door requirements, stile width constraints, and selection criteria that determine which series is correct before the order is placed.

The Four Device Format Decisions That Come Before Series Selection

Choosing a Von Duprin series starts with four decisions that narrow the field immediately. Getting these right eliminates most specification errors before a series number is even considered.

Rim, SVR, CVR, or mortise? Rim devices latch at a single strike on the door frame, the simplest installation, suitable for single doors and pairs with a center mullion. Surface vertical rod (SVR) devices add a top rod engaging the frame header and a bottom rod engaging the floor, providing three-point engagement on double doors without a center post. Concealed vertical rod (CVR) devices run the same three-point engagement with the rod hardware inside the door, for applications where surface rods are architecturally unacceptable. Mortise devices integrate a full mortise lock body into the exit device chassis, providing the deepest security engagement at the door edge.

Wide-stile or narrow-stile? Most commercial hollow metal doors use wide-stile devices. Aluminum storefronts and narrow-frame glass doors require narrow-stile devices with a minimum stile clearance as low as 1-3/4 inches. Using a wide-stile device on an aluminum storefront frame is a dimensional incompatibility: the fasteners run out of material before they engage. The series selection determines which stile width is supported.

Fire-rated or non-fire-rated? Fire-rated configurations carry UL listing for fire door assemblies and remove the dogging function, because fire doors must latch automatically every time the door closes. Specifying a non-fire-rated device on a fire-rated opening fails the UL assembly listing. Specifying a fire-rated device on a non-fire-rated opening costs the dogging function unnecessarily. The "-F" suffix in the model number designates fire-rated configuration.

Electrified or mechanical-only? Von Duprin produces electrified upgrade options including quiet electric latch retraction (QEL), motorized electric latch retraction (MEL), Chexit delayed egress, and Allegion Connect integration. These are available on most push pad and touchbar series. The crossbar series (55 and 88) are mechanical-only by design. If access control integration is required at the device level, the series selection must support electrified options.

The Push Pad Series: Matching Traffic Level and Institutional Requirement

Von Duprin 22 Series: Medium-Traffic Commercial Applications

The 22 Series is the cost-effective Grade 1 specification for medium-traffic commercial openings where proven reliability is needed without institutional-level specification depth. Employee entrances, parking stairwells, back-of-house retail doors, and multi-family corridors are its primary applications. It carries ANSI A156.3 Grade 1 certification and UL listing for panic and fire hardware.

Available in rim and SVR configurations. Electrified options include ALK alarm kits, QEL modular conversion, and MEL motorized latch retraction. Select the 22 Series when the opening is not a primary institutional egress point and the specification does not require the full electrified options depth of the 98/99 Series.

Von Duprin 75 Series: Standard Commercial Grade 1

The 75 Series is the specification for standard commercial buildings: healthcare facilities, offices, and light institutional openings that require Grade 1 performance without the full institutional specification weight of the 98/99. Rim, SVR, and CVR configurations are available. Electrified options include ALK, MEL, QEL modular conversion, and Allegion Connect. The 75 Series sits between the 22 and 98/99 in specification depth and cost, covering the wide middle ground of commercial construction.

Von Duprin 98/99 Series: Institutional Flagship

The 98/99 Series is the dominant institutional specification across North America. Schools, hospitals, universities, government buildings, and any opening where ANSI Grade 1 performance at the highest specification depth is required. The 98 Series has a smooth mechanism case; the 99 has a grooved case. Every internal component is interchangeable between the two.

Configurations: rim, SVR, CVR, WDC (wide door cable), and the 9875/9975 mortise device. Electrified options are the deepest in the Von Duprin lineup: QEL, MEL, Chexit delayed egress, Allegion Connect, signal switches, and electric power transfers. A mechanical 98/99 device specified today can be upgraded to electrified access control years later without replacing the device body. That forward compatibility is why architects and security consultants default to this series on complex institutional projects.

Select the 98/99 when the opening requires the highest specification tier, when electrified integration is required now or anticipated in the future, or when the facility is an institutional building with a contract hardware specification calling for the flagship series.

The Touchbar Series: When the Full-Width Bar Changes the Function

Von Duprin 33/35A Series: Narrow-Stile Touchbar

The 33/35A Series is the touchbar device for aluminum storefronts and narrow-stile applications. The touchbar runs the full width of the door, engaging the release mechanism anywhere along its length, not just at a pad. The 35A has a smooth mechanism case; the 33A has a grooved case. Both fit door stiles as narrow as 1-3/4 inches, which is exactly the stile dimension of most aluminum storefront frames.

This is the series that resolves the most common specification error in commercial glass door hardware: attempting to install a 98/99 Series wide-stile device on an aluminum storefront frame. The 98/99 will not mount properly on a 1-3/4-inch aluminum stile. The 33A/35A is the narrow-stile sibling of the 98/99 family, engineered for that specific application.

The 35A adds an integral door position switch. Configurations cover rim, SVR, CVR, WDC, and the 360/E360 control trim variants. The electrified options catalog is second only to the 98/99 in depth, including Chexit, E7500 electrified mortise lock, pneumatic options, and Allegion Connect. Select the 33A/35A for aluminum storefronts, narrow-stile wood doors, or any application where a touchbar across the full door width is specified over a push pad.

The Crossbar Series: Heavy-Duty Mechanical Applications

Von Duprin 55 Series: Narrow-Stile Crossbar With Mortise Lock Body

The 55 Series is the narrow-stile crossbar device for applications requiring the visual and mechanical profile of a traditional crossbar with the security depth of a mortise lock body. It is constructed of cast brass or bronze plated to the specified finish, which gives it the aesthetic weight appropriate for historic renovations, ornate institutional lobbies, and architectural settings where a utilitarian push pad device would be out of place. The 7500 mortise lock body runs inside the chassis. Configurations include rim, CVR, and the 5575 mortise device.

Von Duprin 88 Series: Wide-Stile Crossbar for Abuse-Resistant Applications

The 88 Series is the heavy-duty wide-stile crossbar device for correctional facilities, behavioral health units, secure government floors, and any application where hardware faces sustained deliberate force. The crossbar has been in continuous production since the 1950s. It ships at 42 inches and is field-cut to door width. It is mechanical-only by design, with no electrified options at the device level. That is a deliberate engineering choice, not a limitation: in environments where electronic components can be targeted or defeated, mechanical robustness is the specification.

Configurations: rim (88/88-F), SVR (8827/8827-F), CVR (8847-F), and mortise (8875/8875-F). Fire-rated versions carry a 3-hour UL listing. The 88 Series is the answer when the application is institutional, the hardware will face abuse, and electrified options are neither required nor appropriate.

The Narrow-Stile Push Pad Series

Von Duprin 78 Series: Aluminum Frame and Glass Storefront Push Pad

The 78 Series is the narrow-stile push pad device specifically engineered for aluminum-frame and all-glass storefront doors with stile widths as narrow as 1-3/4 inches. It is the push pad equivalent of the 33A/35A touchbar: the correct specification when a push pad format is required on a glass storefront door rather than a touchbar.

Configurations include rim, SVR, CVR, and WDC. Electrified options include ALK, MEL, QEL modular conversion, and Allegion Connect. Parts from standard wide-stile series do not cross to the 78 Series. If the opening is an aluminum storefront door and the specification calls for a push pad rather than a touchbar, the 78 Series is the correct selection.

The Mortise and Concealed Series

Von Duprin 94/95 Series: Concealed Vertical Rod for Aesthetic Applications

The 94/95 Series is the CVR device for applications where surface-mounted rods are not architecturally acceptable and the hardware must disappear inside the door. Hotels, premium healthcare interiors, high-end commercial spaces. Configurations cover the 94/9547 CVR device and the 9575 mortise device. Electrified options include the E7500 electrified mortise lock and QEL.

The Double Door Decision: When to Add a Mullion

On double door openings without a center post, the SVR configuration from the appropriate series handles three-point engagement at the header and floor. On openings where a center post is acceptable, the 54 Series Mullion provides the center strike point, allowing one leaf to run a rim device and the other to run an SVR, which is a cost-saving specification on some applications.

The 1609 strike is used specifically on double door applications without a center post, when one leaf uses an SVR and the other uses a rim device. The 1609 is not rated for fire doors, which matters on interior corridor specifications where fire rating is required.

The Complete Selection Decision Tree

Here is the framework that resolves most specification decisions:

Is the door an aluminum storefront or narrow-stile frame? 

Yes: 33A/35A (touchbar), 78 Series (push pad), or 55 Series (crossbar) No: continue below

Is the application correctional, behavioral health, or high-abuse?

 Yes: 88 Series (wide-stile crossbar, mechanical-only) No: continue below

Is access control integration required now or anticipated? 

Yes: 98/99 Series (deepest electrified options) No: continue below

Is this a high-traffic institutional building? 

Yes: 98/99 Series No: standard commercial, moderate traffic: 75 Series No: medium traffic, cost-sensitive: 22 Series

Does the opening require concealed hardware?

 Yes: 94/95 Series CVR, or CVR configuration within the appropriate series above

Why Sourcing Correctly Starts With Specification

Every series selection above has consequences for parts sourcing that compound over the device's service life. A 78 Series part will not fit a 33A/35A. An 88 Series center case kit does not cross to the 22 Series. Confirming the series at specification time is what makes every maintenance, repair, and upgrade decision for the life of the opening accurate.

Security Parts organizes the complete Von Duprin exit devices catalog by series and model, with interactive parts diagrams on every model page. The Von Duprin brand catalog covers all fourteen series with model-specific parts organization and same-day shipping on stocked components. Pre-order support at 845-935-0301 or sales@securityparts.com for specification questions before an order is placed.

Conclusion

The Von Duprin series lineup spans every commercial egress application from a standard office entry to an aluminum glass storefront to an institutional correctional facility. The 22, 75, and 98/99 Series cover the push pad spectrum from medium-traffic commercial through heavy institutional. The 33A/35A and 78 Series cover narrow-stile aluminum and glass doors in touchbar and push pad formats. The 55 and 88 Series cover crossbar applications in narrow-stile aesthetic and wide-stile abuse-resistant configurations. The 94/95 Series covers concealed vertical rod applications where surface rods are unacceptable. Every series selection determines parts compatibility, electrified upgrade paths, and fire rating eligibility for the life of the opening. Start at the door type, confirm the stile width, determine the traffic and security tier, and the series selection follows logically. Browse the complete Von Duprin series catalog with model-specific parts diagrams at Security Parts.

FAQs

What is the difference between the Von Duprin 22 and 98/99 Series?

 The 22 Series is the mid-range Grade 1 specification for medium-traffic commercial openings. The 98/99 Series is the institutional flagship with the deepest electrified options catalog and broadest configuration range. Both are ANSI A156.3 Grade 1 certified.

Which Von Duprin series fits aluminum storefront doors? 

The 33A/35A Series for touchbar devices and the 78 Series for push pad devices. Both accommodate stile widths as narrow as 1-3/4 inches. Standard wide-stile Von Duprin devices like the 98/99 will not mount correctly on aluminum storefront frames.

What Von Duprin series is specified for correctional facilities?

 The 88 Series. It is a heavy-duty wide-stile crossbar device built for abuse-resistant applications with no electrified options at the device level. It has been in continuous production since the 1950s and carries ANSI A156.3 Grade 1 certification.

Can I upgrade a mechanical Von Duprin device to electrified access control?

 On the 98/99, 22, 33A/35A, 75, and 78 Series, yes. QEL modular conversion kits and MEL motorized latch retraction are available as field-installable upgrades without replacing the device body. The 55 and 88 crossbar series do not support electrified device options.

What is the difference between a rim and SVR Von Duprin exit device? 

A rim device latches at a single frame-side strike, for single doors or pairs with a center mullion. A surface vertical rod (SVR) device adds top and bottom engagement points via surface-mounted rods, for double door openings without a center post.

Does the Von Duprin 55 or 88 Series fit aluminum storefront doors?

 No. The 55 Series is a narrow-stile crossbar in cast brass, for historic and aesthetic applications on non-aluminum doors. The 88 is a wide-stile crossbar for institutional applications. Aluminum storefront narrow-stile applications use the 33A/35A or 78 Series.