The Schlage CS210 is the CS200 Series Grade 2 interconnected lock. It combines a cylindrical latch and deadbolt in one assembly so turning the inside lever retracts both simultaneously in one motion, meeting IBC and NFPA 101 single-motion egress requirements. The main replacement parts are the lever kit (06-242), rose (08-029), inside escutcheon (Camelot or Plymouth), outside housing (B500 commercial or B60 residential), strikes, and the interconnect assembly. The crimp-to-snap rose transition in August 2015 is the most important fact for parts ordering: pre-2015 units with crimp-on roses require the outside chassis assembly (F206-496) when changing levers or roses.

Interconnected locks are on more apartment building, hotel, dormitory, and assisted living entry doors than any other lock type in the multifamily residential sector. They are specified because they solve a specific problem that no other single hardware component solves: providing both a spring latch for automatic latching and a deadbolt for security, while allowing a single inside lever motion to retract both simultaneously for code-compliant egress.

The Schlage CS210 is the most widely installed commercial interconnected lock in North America. It carries ANSI/BHMA Grade 2 certification, UL 3-hour fire door listing, and a lifetime limited mechanical warranty. When one fails or requires a lever change, rose replacement, or escutcheon update, the rose generation transition in 2015 creates a parts compatibility issue that catches most technicians off guard. This guide covers every component, that transition, the code context, and exactly how to order. Browse the complete interconnected lock parts catalog at SecurityParts.com for CS210 diagrams and components.

What an Interconnected Lock Is and Why It Exists

An interconnected lock is a single hardware assembly that combines two separate locking mechanisms, a spring latch and a deadbolt, with a mechanical interconnection that allows both to retract simultaneously when the inside lever is turned. From the outside, the lock operates as a standard keyed deadbolt entry. From the inside, turning the lever once retracts both the deadbolt and the latch in a single motion, allowing free exit without any separate deadbolt thumb turn operation.

This single-motion egress capability is the entire reason the category exists. IBC Section 1010.1.9 and NFPA 101 both require that doors in a means of egress unlatch with no more than one releasing motion. For most commercial occupancies, installing a separate cylindrical latch and a separate deadbolt creates a two-motion exit requirement that violates this code, because the occupant must turn the deadbolt thumb turn and then turn the lever separately to exit.

The interconnected lock solves this by making the inside lever turn the only operation needed for exit. The deadbolt and latch both retract together. The door opens. One motion. Code compliant.

Where the Schlage CS210 Is Specified

The CS210 appears most frequently on dwelling unit entry doors in commercial multi-family buildings: apartment complexes, condominiums, dormitories, extended-stay hotels, and assisted living facilities. The specific application logic that drives the CS210 specification is the need for resident-facing security with single-motion egress in a commercial-grade fire-rated assembly.

Assisted living facilities are a particularly important distinction. Assisted living units are classified as Residential Board and Care occupancies under NFPA 101, not standard residential occupancies. The residential dwelling unit exception that allows a separate deadbolt does not apply to assisted living units. On assisted living dwelling unit entry doors, an interconnected lock or mortise lock is required in most jurisdictions because a separate deadbolt and latchset do not comply with one-motion egress for this occupancy type.

For institutional dormitories, hotel properties, and any jurisdiction with accessible or adaptable unit requirements, interconnected locks are often specifically mandated by local code supplements to the IBC. Massachusetts 521 CMR, for example, explicitly requires interconnected locks on accessible and adaptable dwelling units.

CS210 vs Separate Deadbolt vs Mortise Lock: Which One Fits the Opening

Every Component in the Schlage CS210

Outside Housing Assembly: B500 vs B60

The CS210 offers two outside deadbolt housing configurations. This is the first specification decision and it determines the security level of the entire assembly.

CS210-B500 (commercial spin ring): The B500 outside housing includes a free-spinning cylinder collar that resists wrenching and prying. It also includes a removeable security shield that protects the deadbolt from ice-pick attacks through the door face. These are the same security features found in the Schlage B600 Series Grade 1 deadbolt. The B500 housing is the correct specification for any commercial or institutional application where physical attack resistance matters. The cylinder collar spins freely under wrench pressure rather than providing purchase for torque.

CS210-B60 (residential spin ring): The B60 housing is the residential version for multi-family buildings where the aesthetic and cost profile of a residential deadbolt is appropriate and the additional attack resistance features of the B500 are not required by the specification.

Lever Kit (Part 06-242)

The CS210 lever kit (part 06-242) includes two matching levers, one outside and one inside. The CS200 Series offers 18 lever designs allowing the CS210 to match the aesthetic of other Schlage hardware throughout the same building. Lever designs are available in seven finishes including satin chrome (626), brushed nickel (619), matte black, polished brass (605), aged bronze, and others.

Lever replacement is needed when a lever is physically damaged, when a finish change is required after a renovation, or when a lever becomes stiff or fails to return to horizontal due to internal spring fatigue. The lever kit includes both levers, which keeps inside and outside matching during replacement. Always confirm the finish code before ordering a replacement lever kit.

Rose (Part 08-029)

The rose is the circular cover plate visible on the door face around the outside lever and cylinder area. The CS210 offers two outside rose designs: Plymouth and Saturn. The rose is finish-specific. Part 08-029 is the standard rose for snap-on rose installations (August 2015 and later). For crimp-on rose installations (pre-August 2015), see the crimp-to-snap section below before ordering any rose replacement.

Inside Escutcheon: Camelot (CAM) and Plymouth (PLY) Designs

The inside escutcheon is the decorative plate on the interior face that covers the inside chassis and positions the inside lever and thumb-turn plate. The CS210 offers two inside escutcheon designs: Camelot (CAM) and Plymouth (PLY). Both designs are available in the same seven finishes as the levers.

The inside escutcheon houses the adjustable thumb-turn plate assembly that supports both the 4-inch and 5-1/2-inch center-to-center door prep conversions. The escutcheon plate adjustment is a field modification; no additional parts are ordered for a center-to-center conversion. If the escutcheon itself is damaged or a design change is required, the escutcheon is an individually replaceable component.

Interconnect Assembly

The interconnect assembly is the internal mechanism that links the inside lever to both the deadbolt and latch, enabling the simultaneous retraction in one motion. This is the component that makes an interconnected lock different from a standard cylindrical lock with a separate deadbolt.

The interconnect assembly carries the load of both the deadbolt spring and the latch spring when the inside lever is turned. This combined spring load requires slightly more torque to operate than either a latch-only or deadbolt-only lock. The design intent is that a healthy adult requires no additional force beyond a normal lever turn. However, the combined spring load can become problematic for elderly, infirm, or physically limited occupants on doors where both springs are at the high end of their adjustment range. If a CS210 installation is reporting difficulty operating the lever, check that neither spring is adjusted beyond the standard setting before assuming the interconnect assembly has failed.

Interconnect assembly replacement is required when the inside lever turns but only one of the two mechanisms (latch or deadbolt) retracts, when the interconnect binding causes the lever to feel mechanically stiff at a specific point in its rotation arc, or when the assembly fails to fully return to the latched position after a lever release. Center-to-center conversion (4 inch to 5-1/2 inch or reverse) is made by a field modification to the interconnect assembly without requiring a replacement part.

Strike Plate (Part 10-109 and 10-121 Combination Strikes)

The CS210 uses a combination strike that includes both a deadbolt strike and a deadlatch strike in a single plate assembly. Both strikes must be correctly positioned in the door frame for the lock to operate without binding. The CS210 standard combination strike is part 10-109. The 10-121 is an alternate combination strike. A T-strike (1-5/8 inch by 2-1/4 inch) is also available for the deadbolt portion.

Strike alignment is the most common cause of a CS210 installation that feels stiff or incomplete on either the deadbolt throw or the latch engagement. Because the CS210 operates two mechanisms simultaneously, even minor vertical misalignment of either strike pocket creates binding that feels like internal mechanism failure. When a CS210 is reported to be stiff or incomplete in its operation, verify both strike alignments before diagnosing internal components.

The CS210 also includes a metal wood frame reinforcer using 3-inch screws that anchor into the door frame stud for kick-in resistance. This is the same dust box concept as the B Series deadbolt and its presence significantly increases the resistance of the frame to forced entry. It should always be installed and is not optional on any security-sensitive application.

Deadbolt Strike (Part 10-116)

The deadbolt-only strike (part 10-116) is a round corner strike, 1-1/8 inch by 2-3/4 inch, no lip. This is used when the deadbolt and latch have separate frame preps rather than a combined pocket. Always confirm whether the installation uses a combination strike or separate strikes before ordering replacement hardware.

The Crimp-On to Snap-On Rose Transition: The Most Important CS210 Service Fact

In August 2015, Schlage transitioned the CS210 from crimp-on roses to snap-on roses. This transition is completely undocumented in most parts supplier catalogs and is the single most common cause of wrong-part returns on CS210 service calls.

How to Identify Which Generation Your Lock Is

Remove the outside rose from the door face. Examine the base of the rose where it meets the door surface. Snap-on roses have retention dimples at the base. Crimp-on roses do not have these dimples and have a smooth or rolled edge at the base instead. If you are not certain which generation is installed, this physical check takes under two minutes and prevents an incorrect parts order.

What Happens If You Order the Wrong Generation

The lever kit (06-242) and rose (08-029) designed for snap-on rose installations cannot be used on a crimp-on rose chassis. The retention mechanism is physically different and the lever will not seat correctly. If you have a pre-August 2015 installation with a crimp-on rose and order the current lever kit without also updating the outside chassis, the parts will not function correctly after installation.

The Correct Crimp-On to Snap-On Upgrade Parts

For a pre-August 2015 crimp-on rose installation that needs a lever or rose replacement, order all four of these components together:

Center-to-Center Door Prep Conversion: Field Modification Without Parts

The CS210 adjustable escutcheon plate supports both 4-inch and 5-1/2-inch center-to-center door preparations. This is the dimension between the centerline of the deadbolt bore and the centerline of the cylindrical latch bore on the door face.

The conversion is made entirely in the field by modifying the interconnect assembly position inside the escutcheon plate. No additional parts are required and no replacement components need to be ordered. The procedure is:

For 4-inch center-to-center: Remove two screws and the plate from the escutcheon assembly. Position the thumb-turn assembly with the thumb turn toward the bottom of the thumb-turn escutcheon plate.

For 5-1/2-inch center-to-center: Keep the plate in place with the two screws. The thumb-turn remains in its standard position.

This field adjustability is the design feature that eliminates job-site surprises when the existing door prep does not match a specific standard. A building with mixed 4-inch and 5-1/2-inch door preps can use the same CS210 lock on every unit door without ordering two different lock configurations.

CS210 Technical Specifications

Parts That Fail First on the Schlage CS210

Based on actual field service frequency, here is the realistic replacement sequence for CS210 components on high-traffic multi-family installations.

1. Levers. The outside lever takes physical contact on every door entry and exit. Finish wear is the most common cosmetic issue. Physical damage from cart impact or door abuse is the most common functional issue. The lever kit (06-242) replaces both inside and outside levers. Always check the rose generation before ordering (crimp vs snap as described above).

2. Strike plate alignment. This is not a parts failure but a maintenance item. Door settling in multi-family buildings causes progressive strike misalignment that shows up as a stiff deadbolt throw, incomplete latch engagement, or a lever that requires more force than normal. Check both strike alignments before diagnosing internal components. Re-securing loose strike screws or adjusting the strike position resolves most CS210 stiffness complaints without any parts replacement.

3. Cylinder. The 6-pin C keyway cylinder in the CS210 wears at the same rate as any commercial cylinder under high-cycle use. Key stiffness or a key that operates inconsistently indicates cylinder wear. As with all Schlage cylinders, use only graphite or silicone lubricant. Oil-based lubricants accelerate pin stack contamination and require cylinder replacement.

4. Inside escutcheon assembly. The inside escutcheon is subject to cosmetic damage on unit entry doors where residents are frequently carrying items. A cracked escutcheon plate or a finish that has worn through requires replacement as a complete escutcheon assembly. Confirm the Camelot or Plymouth design before ordering.

5. Interconnect assembly. The internal interconnect mechanism has the longest service life of any component in the CS210 because it is protected inside the door and does not receive direct physical contact. Interconnect failure appears as a lever that retracts one mechanism but not the other, or as an inconsistent combined retraction. Full interconnect replacement is required when this occurs.

Code Compliance: Interconnected Lock vs Separate Deadbolt on Dwelling Unit Doors

The code question that drives most CS210 specifications is whether a separate deadbolt is allowed on a dwelling unit entry door or whether an interconnected lock is required.

Where Separate Deadbolts Are Allowed

IBC Section 1010.1.9 and NFPA 101 both include an exception for Group R residential dwelling units with an occupant load of 10 or less. On these doors, a separate nightlatch, deadbolt, or security chain is permitted in addition to the latching hardware, provided the separate device can be released from the inside without a key or tool. A thumbturn-operated single cylinder deadbolt meets this requirement.

This exception applies to most apartments, condominiums, dormitory rooms, hotel rooms, and similar units. It is the reason separate deadbolts are common on apartment doors throughout the United States. In these jurisdictions, the CS210 is a premium specification option, not a code requirement.

Where Interconnected Locks Are Required

Several situations eliminate the separate deadbolt exception and require one-motion egress on dwelling unit entry doors. The first is when the local jurisdiction has adopted stricter requirements than the model codes. The second is for accessible or adaptable dwelling units in jurisdictions following accessibility standards that mandate one-motion egress hardware. The third is for assisted living and residential board and care facilities where the NFPA 101 residential occupancy exception does not apply. In all three situations, an interconnected lock or mortise lock is the only code-compliant hardware solution for a door requiring both a latch and a deadbolt.

How to Order CS210 Parts Without a Return

Four pieces of information are required before any CS210 parts order:

1. Rose generation (crimp or snap): This is the most important check. Remove the outside rose and look for retention dimples at the base. Dimples = snap-on (August 2015 or later). No dimples = crimp-on (pre-August 2015). If the lock is pre-2015, the outside chassis (F206-496) must be ordered along with the lever kit and rose.

2. Outside housing type (B500 or B60): The B500 has a free-spinning cylinder collar and security shield. The B60 does not. This is visible without disassembly: grip the exterior cylinder collar and attempt to rotate it. Free spin = B500. Fixed = B60.

3. Inside escutcheon design (Camelot or Plymouth): The Camelot design has a more traditional rectangular profile. The Plymouth has a more contemporary rounded shape. Both are visible on the interior door face without disassembly.

4. Finish code: Visible on the hardware face. Common CS210 finishes include 626 (satin chrome), 619 (satin nickel), 622 (matte black), 625 (bright chrome), and 605 (polished brass). All replacement components are finish-specific.

Browse the complete CS210 parts catalog at SecurityParts.com. For the full Schlage commercial hardware range including the CS210, ND Series, L Series, and B Series, browse the Schlage commercial hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Related Parts and Products at Security Parts

A complete multi-family unit entry door typically includes the interconnected lock, a surface door closer (required by fire code for self-closing on fire-rated corridor-to-unit assemblies), and sometimes an electric strike for access control on the corridor side. SecurityParts.com stocks all of these in one catalog.

For Schlage B Series deadbolt parts on unit entry doors where a separate deadbolt is permitted and specified instead of an interconnected lock, browse the deadbolts catalog. For Schlage ND Series and ALX Series cylindrical lock parts on common area corridor doors, mailroom doors, and amenity space doors in the same building, browse the cylindrical locks catalog. For Schlage L Series mortise lock parts on main building entry doors and management office doors requiring Grade 1 performance, browse the mortise locks catalog. For LCN door closer parts on unit entry doors and corridor fire doors in the same building, browse the door closers catalog. For Von Duprin exit device parts on building egress stairwells and exit doors, browse the commercial exit devices catalog.

Browse the complete all products and parts catalog to source Schlage, Von Duprin, LCN, Falcon, and Detex hardware in a single session.

Security Parts carries parts for the Schlage B Series commercial deadbolts. The B600 Series is Grade 1, Schlage's strongest commercial deadbolt. The B500 Series is Grade 2 for lighter applications. The most commonly replaced parts are the tailpiece (driver bar), the cylinder, and the strike plate. If a new B Series installation won't lock or unlock, rotate the driver bar 90 degrees toward the hinges before reinstalling. If the key turns but the bolt doesn't move, the tailpiece is stripped and needs replacement. Never use oil-based lubricants on B Series cylinders. Use graphite or silicone only.

Schlage B Series deadbolts are on more commercial and institutional doors than any other deadbolt brand in North America. They show up on office suites, storage rooms, corridor doors, exterior entries on healthcare and government buildings, and any secondary door on a commercial property that needs a reliable keyed bolt without the complexity of a full mortise lock.

When one fails, the repair is usually one of three things: a worn tailpiece, a failing cylinder, or a misaligned strike plate. Getting the right replacement part requires knowing the series (B500 vs B600), the cylinder format, and in some cases the finish code. This guide covers every component, every failure mode, every function, and the field-tested troubleshooting sequence that identifies the correct part before you order anything. Browse the complete Schlage B Series deadbolt parts catalog at SecurityParts.com for interactive diagrams on every model.

How a Commercial Deadbolt Works

A deadbolt operates differently from a spring latch. A spring latch clicks into the strike automatically when the door closes and retracts when the lever or knob is turned. A deadbolt does neither automatically. It extends only when the cylinder is turned with a key or the thumb turn is rotated, and it retracts only by the same means. Once extended, it cannot be pushed back by end pressure, a credit card, or a shimming tool.

Inside the lock body, the cylinder cam engages the tailpiece when the key is turned. The tailpiece connects the cam to the deadbolt bolt mechanism and drives the bolt in or out. On a single cylinder deadbolt, a thumb turn connects to the same bolt mechanism from the inside. On a double cylinder deadbolt, a key cylinder replaces the thumb turn on the inside.

The deadbolt throw on both B500 and B600 series is 1 inch. On a correctly installed B Series deadbolt, this 1-inch throw passes through the strike plate hole and engages at least 1 inch into the door frame. The metal dust box anchors the strike with 3-inch screws into the frame stud, which is why kick-in attacks that defeat the bolt still fail on a correctly installed B Series with the dust box in place.

B500 vs B600: Choosing the Right Series Before Ordering Parts

B600 Series Security Features: What They Mean for Parts Ordering

The B600 Series has a longer list of anti-attack features than the B500, and several of them directly affect parts compatibility and ordering.

Hardened Steel Anti-Saw Pin

A hardened steel pin is embedded in the deadbolt bolt body perpendicular to the bolt. If someone attempts to saw through the extended bolt, the saw blade hits the hardened pin and stops. The anti-saw pin is part of the bolt assembly and is not a separately replaceable component. If the bolt shows saw damage, the entire bolt assembly must be replaced, not just the pin.

Hardened Steel Ball Bearings on Through Bolts

The through bolts that mount the lock to the door have hardened steel ball bearings embedded in the bolt body. If someone attempts to drill through the bolt to remove the mounting screws, the drill bit contacts the ball bearing and spins without penetrating. These are built into the through bolt hardware and are not separately replaceable. If a through bolt is drilled, the entire bolt set requires replacement.

Free-Spinning Cylinder Collar

The cylinder collar on the B600 exterior is broadly angled and designed to spin freely when a wrench is applied to it. A fixed collar gives a wrench purchase to torque the cylinder out of the lock body. The free-spinning collar denies that purchase and the cylinder cannot be wrenched. The collar is part of the exterior cylinder housing assembly and is finish-specific. When ordering a replacement exterior cylinder assembly for a B600, confirm both the finish code and the security level (standard Everest 29, Primus, or Primus XP) before ordering.

Steel Fire Cup Plate Insert

The fire cup plate insert adds structural strength to the lock body and enables UL listing for 3-hour fire door use as an auxiliary lock. This component is factory-installed in B600 Series locks. It is not a separately field-replaceable component. If a B600 fire-rated installation requires a replacement lock body due to damage, specify the fire-rated version when ordering to ensure UL listing compliance on the fire-door assembly is maintained.

Every Replaceable Component in the Schlage B Series Deadbolt

Tailpiece (Driver Bar): The Most Misdiagnosed Failure

The tailpiece is the flat metal bar that connects the cylinder cam and the thumb turn to the deadbolt bolt mechanism. It is the most frequently misdiagnosed failure on a Schlage B Series deadbolt, and it is also the most common source of new-installation failures that are not actually component failures at all.

Tailpiece part numbers are length-specific and cylinder configuration-specific:

Deadbolt Bolt Assembly

The B500 default bolt is part 12-288 (square corner, 1 inch by 2-1/4 inch, 1 inch housing diameter, adjustable backset 2-3/8 or 2-3/4 inch). The B600 default bolt is part 12-296 (square corner, 1-1/8 inch by 2-1/4 inch, 1 inch housing diameter, adjustable backset 2-3/8 or 2-3/4 inch). Both series offer fixed backset options at 2-3/8, 2-3/4, 3-3/4, and 5 inches in addition to the adjustable standard.

Bolt assembly replacement is needed when the bolt has sustained physical damage from a forced entry attempt, when the anti-saw pin has been encountered by a saw blade, or when the bolt mechanism binds and will not extend or retract cleanly even after lubrication. The bolt faceplate (also called the drive-in faceplate) is a separately replaceable component that covers the bolt hole on the door edge and can be replaced without replacing the full bolt assembly when only the faceplate is damaged.

Cylinder Assembly

The cylinder is the keyed component in the exterior rose that drives the cam, which drives the tailpiece, which moves the bolt. The B Series supports multiple cylinder formats at ordering time:

When replacing a B Series cylinder, confirm the security level installed before ordering. A standard Everest 29 cylinder looks physically identical to a Primus cylinder from the outside. The security level is on the original specification or on the key, which will have Primus branding on a Primus cylinder. Installing a standard cylinder to replace a Primus cylinder downgrades the security level of the opening without any visible indication that a change has been made.

Strike Plate and Metal Dust Box

The B600 standard strike is 1-1/8 inch by 2-3/4 inch with square corners. The B500 standard strike is 1-1/8 inch by 2-3/4 inch. Both are available in ANSI curved lip, round cornered, and thimble configurations for different frame preparations.

The metal dust box (part B520-283) is installed behind the strike plate. It creates a reinforced pocket in the frame for the bolt to enter, and its 3-inch screws anchor into the door frame stud rather than just the door frame face. This is what gives the B Series its resistance to kick-in attacks. The bolt itself can withstand the force. What fails on most deadbolt kick-in attacks is the door frame around the strike, not the bolt or the lock body. The metal dust box with 3-inch screws prevents frame failure by distributing the force into the stud.

Thumb Turn Assembly

The thumb turn is the interior control on a single cylinder deadbolt that allows the bolt to be thrown or retracted from the inside without a key. The thumb turn assembly includes the turn itself, the rose, and the connecting components to the bolt mechanism. On a double cylinder deadbolt, the thumb turn is replaced by an interior key cylinder and the interior rose assembly changes accordingly.

Thumb turn replacement is needed when the turn becomes stiff or will not rotate fully, when physical damage to the thumb turn has occurred, or when the connection between the turn and the bolt mechanism has worn. The thumb turn assembly is finish-specific. Always confirm the finish code before ordering a replacement.

On a correctly installed lock, the thumb turn should operate with minimal resistance in either direction. A thumb turn that requires two-hand force to operate is not a characteristic of a fully functioning deadbolt. Check for strike plate misalignment before assuming the thumb turn mechanism has failed, as binding caused by a slightly misaligned strike is often mistaken for internal mechanism failure.

Exterior Rose and Cylinder Guard

The exterior rose is the cover plate visible on the door face around the cylinder. On the B600 Series, the exterior rose houses the free-spinning cylinder collar and acts as the primary tamper-resistant interface between the exterior and the door. The exterior rose is finish-specific. Scratch or impact damage to the rose requires a finish-matched replacement. The cylinder collar is part of the exterior assembly and is not separately replaceable from the rose on most B600 configurations.

B Series Deadbolt Functions: What Each One Does

The Schlage B Series deadbolt functions determine the operating configuration and the trim components required. Ordering a replacement cylinder, tailpiece, or trim without confirming the function code produces parts that may not be compatible with the specific installation.

The B600 Indication Trim: Why It Matters for Parts

The B600 indication trim function uses a patented 180-degree viewing window that wraps three sides of the exterior rose and displays a red or white background with LOCKED or UNLOCKED messaging. The large window is readable even from across a corridor. This is the "Know It's Locked" feature Schlage markets for healthcare and education applications where knowing a room's lock status without touching the hardware is a daily operational requirement.

The indication trim is not interchangeable with standard trim. It requires a specific exterior rose assembly with the viewing window housing. When ordering a replacement rose for a B600 indication trim installation, confirm the indication function variant before ordering. A standard rose does not retrofit into an indication trim installation because the housing geometry is different.

The B600 indication trim is available with red and white messaging backgrounds for readability by color-blind individuals, and in English, French, and Spanish language versions. Always confirm the language version when ordering a replacement trim assembly for an indication function installation.

Tailpiece Orientation: The Fix Nobody Documents Clearly

The official Schlage troubleshooting guide documents a specific procedure for a newly installed B Series deadbolt that will not lock or unlock. Most other resources on the internet describe this problem as a defective lock. It is not a defective lock in the overwhelming majority of cases.

The tailpiece has an orientation that must be set correctly relative to the door for the lock to function. If installed in the wrong orientation, the key turns, the thumb turn moves, but the bolt does not extend or retract. The fix takes under two minutes.

Key-Sticking and Cylinder Failure: When to Replace vs Lubricate

A stiff key on a B Series deadbolt is one of the most common service calls. The correct response depends on how long the stiffness has been present and what lubricant history the cylinder has.

New or recent installation, key stiff immediately: Check the cylinder alignment in the rose. A slightly off-center cylinder causes the key to bind against the cylinder housing on entry. Verify the exterior rose is seated flush before assuming cylinder failure.

Key stiff after months or years of use, never lubricated: Apply graphite powder to the key blade and work it in and out of the cylinder several times. For most B Series cylinders in commercial service, graphite applied every 12 months is sufficient maintenance. Do not use WD-40 or any oil-based product.

Key stiff after months or years of use, previously lubricated with oil-based product: The pin stack has collected oil-carried debris. Graphite will not flush this out. The cylinder requires replacement. Part numbers for B600 replacement cylinders must match the security level (standard Everest 29, Primus, or Primus XP) of the original installation.

Key turns freely but bolt does not move: The tailpiece connection has failed. The key is operating the cam but the cam is no longer driving the tailpiece into the bolt mechanism. Remove the lock, inspect the tailpiece for wear or stripping, and replace with the correct length tailpiece (B202-557 for standard doors or B202-558 for thicker doors).

Key can only be removed in one position (locked or unlocked) but not the other on a new installation: Rotate the driver bar fully toward the hinges and reinstall. This is a tailpiece orientation issue identical to the general non-operating procedure above.

Strike Plate Alignment: The Most Common Source of Binding

A deadbolt that operates smoothly with the door open but feels stiff or fails to fully extend when the door is closed is almost always a strike plate alignment problem. The bolt pocket in the strike must be centered on the bolt throw for the bolt to enter cleanly and without side friction.

Door settling is the most common cause of gradual strike plate misalignment in commercial buildings. Wood frame doors settle as the building ages and the door shifts slightly in its frame. Hollow metal frame doors can shift if the frame anchoring fasteners loosen over time. Either way, the result is a bolt that contacts the edge of the strike pocket rather than entering it cleanly.

Correcting strike plate misalignment does not always require a new strike. If the misalignment is small (2mm or less), enlarging the bolt pocket with a chisel is the fastest correction. If the misalignment is larger, the strike must be relocated or a new strike installed with a bolt pocket at the corrected position.

A strike that has been in service for 10 or more years on a high-traffic exterior door may also show deformation of the bolt pocket lip where repeated bold throw impact has worn or bent the steel. A deformed strike produces a deadbolt that feels rough on every locking cycle. Replace the strike when deformation is visible.

How to Identify Your B Series Model Before Ordering Parts

Three pieces of information are required before any B Series parts order.

1. Series designation (B500 or B600): The series is stamped or labeled on the lock body, visible when the interior assembly is removed. If the label is missing or worn, the grade level can sometimes be identified by the security features: if the exterior cylinder collar spins freely when gripped and twisted, it is a B600. If it is fixed, it may be a B500 or an older B series.

2. Cylinder security level: Standard Everest 29, Primus, or Primus XP. The key itself will have Primus branding if a Primus cylinder is installed. UL 437 markings on the cylinder face confirm Primus XP. Ordering a standard cylinder to replace a Primus cylinder downgrades security without any visible indication to building management.

3. Finish code: The finish is on the original specification or visible on the hardware. Common B Series finishes include 605 (bright brass), 619 (satin nickel), 622 (matte black), 625 (bright chrome), 626 (satin chrome), and 643e (aged bronze). Trim components are finish-specific. A replacement thumb turn or rose in the wrong finish requires a return and reorder.

Browse the Schlage B Series deadbolt parts catalog at SecurityParts.com for interactive diagrams by model. For the complete Schlage commercial hardware range including ND Series cylindrical locks, L Series mortise locks, and B Series deadbolts, browse the Schlage commercial hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Related Parts and Products at SecurityParts.com

Schlage B Series deadbolts are typically installed alongside cylindrical locksets on the same door or in the same building. A complete commercial service call for a building's lock hardware often covers all of these at once.

For Schlage ND Series, ALX Series, and Falcon T Series cylindrical lock parts on interior corridor and office doors in the same facility, browse the cylindrical locks catalog. For Schlage L Series and Falcon MA Series mortise lock parts on high-security entry doors in the same building, browse the mortise locks catalog. For Von Duprin electric strike parts on access-controlled entries in the same facility, browse the electric strikes catalog. For Von Duprin and Falcon exit device parts on egress doors in the same building, browse the commercial exit devices catalog. For LCN door closer parts on any door with automatic closing hardware, browse the door closers catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware in a single session.

Mortise locks are the most complex mechanical lock type to source replacement parts for because the function code determines which components are correct, and parts across different function codes are not interchangeable even when the cases look identical. SecurityParts.com carries parts for the Schlage L Series Grade 1 (40-plus functions, 33 lever styles) and Falcon MA Series Grade 1 (high-traffic institutional, SFIC-compatible). The function code, door handing, and manufacture date are all required before ordering any chassis, armor front, latchbolt, spindle, or cylinder cam. The L9050 universal case is the single most important inventory item because it can be transformed into nine different L Series functions with the right additional parts.

Mortise locks outlast cylindrical locks by a factor of 3 to 5 in commercial service. They are on the entry doors, the main corridors, the healthcare and government facilities where reliability is not optional. When one needs service, the parts tree is deeper and more function-specific than anything in the cylindrical lock world.

The Schlage L Series alone covers more than 40 functional options, 33 lever designs, and 14 finishes. Its parts split into chassis components, cylinder components, trim components, and function-specific parts that are not interchangeable even within the same L Series family. A lever return spring for an L9010 passage function is not the same servicing need as a spindle assembly for an L9080 storeroom function. Getting any one of these wrong means a return, a reorder, and a door that stays out of service for another week. Browse the complete mortise lock parts catalog at SecurityParts.com for interactive diagrams on every function and model.

How a Mortise Lock Differs from a Cylindrical Lock

A mortise lock installs into a pocket (the mortise) cut into the edge of the door, typically 4 inches deep, 6 inches tall, and 1 inch wide. The entire lock mechanism lives inside this pocket with only the armor front plate visible on the door edge and the levers and roses visible on the door face. This concealed mounting is what gives mortise locks their tamper resistance advantage over cylindrical bore locks where the mechanism is partially exposed.

Inside the mortise case, the mechanism includes a spring latchbolt for automatic latching, an auxiliary deadlatch plunger that deadlocks the latchbolt when the door closes against the strike, a separate deadbolt on many functions, a spindle connecting the inside and outside levers through the case, and a mortise cylinder that controls the deadbolt cam. All of these operate in a single cast body. This is what makes mortise locks the strongest lock type for high-security commercial doors but also the most complex to source replacement parts for correctly.

Schlage L Series: The Commercial Benchmark Mortise Lock

The Schlage L Series has been the benchmark commercial mortise lock specification in North America for decades. Government buildings, healthcare facilities, higher education campuses, institutional projects. If a building was built to a commercial standard after 1970, there is a very high probability it has L Series locks on the entry and secured doors.

The L Series offers beyond-Grade-1 strength in a mortise chassis. The anti-saw pin in the deadbolt prevents cut-through attacks. The security blocking hub prevents lock access by removing the levers. Lock monitoring options including request to exit (RX), latchbolt monitoring (LX), door position sensor (DPS), and deadbolt monitoring (DM) are available depending on the function. The patented Everest 29 S123 keyway prevents unauthorized key duplication as standard. Primus restricted cylinders with geographic exclusivity and advanced key control are available for facilities requiring maximum key system security.

Reading the Schlage L Series Model Number

The model number decodes every specification needed to source the correct replacement parts. The format is L or LV plus function group plus deadbolt indicator plus cylinder suffix.

The Most Common Schlage L Series Functions

The L9050 Universal Case: The Most Important Inventory Item

Schlage designed the L9050 universal case to be transformed into nine different L Series functions by adding specific conversion components. This is the single most important piece of knowledge for facilities managers who maintain large L Series inventories.

A facility stocking the L9050 universal case can reconfigure it for passage, entrance/office, classroom, storeroom, and other functions using the Schlage Universal Transformation Guide (document 109436). The guide specifies exactly which additional parts are required for each function conversion. This approach eliminates the need to stock nine separate configured cases and eliminates the lead time required to order an uncommon factory-configured function combination.

The transformation requires only a few additional parts per function change, typically a chassis conversion kit and potentially trim components. The labor time is minimal for a locksmith familiar with the L Series. For facilities with 50-plus L Series locks across multiple functions, this single knowledge point eliminates thousands of dollars in stocked inventory and weeks of lead time across the building's service life.

Every Replaceable Component in the Schlage L Series

Lock Case (Chassis)

The Schlage L Series chassis (also called the lock case or case body) is the cast iron or steel housing that lives inside the mortise pocket. The chassis contains the latchbolt mechanism, the auxiliary deadlatch plunger, the deadbolt (on applicable functions), the spindle hubs, the cylinder cam track, and the internal function mechanism. The base chassis for L9050 is part L283-133. The LV-series Vandlgard chassis substitutes the standard function mechanism with the Vandlgard clutch assembly that prevents forced lever torque from engaging the deadbolt or latch.

Chassis replacement is required when the internal mechanism fails, when a function change is needed on an ND-style installation, or when the case sustains physical damage from a break-in attempt. Chassis replacement requires door disassembly, which typically means removing the levers, roses or escutcheons, through-bolts, and the case itself from the mortise pocket. Always verify the backset (2-3/4 inch standard on L Series) and door thickness accommodation before ordering a replacement case.

Latchbolt Assembly

The latchbolt is the beveled spring bolt that extends from the lock case and clicks into the strike plate when the door closes. On the Schlage L Series, the standard latchbolt is a two-piece deadlocking latchbolt with a separate auxiliary plunger alongside the main bolt. The auxiliary plunger, when depressed by the strike plate face on door closing, deadlocks the latchbolt against being retracted from the latch edge by a shimming tool or card.

The two-piece construction means the main bolt and the auxiliary plunger are separate components within the latchbolt assembly. If the auxiliary plunger fails to depress or return correctly, the deadlocking function is compromised even though the latch itself still operates normally. This is a silent failure: the door latches and appears secure but the deadlocking protection is absent. Inspect the auxiliary plunger on any L Series installation where security has been questioned, even if the latch seems to operate normally.

Armor Front (Armored Front / Scalp Plate)

The armor front is the hardened steel face plate visible on the door edge that covers the mortise case opening. It presents the latchbolt and deadbolt holes aligned with the case components below, and it resists pry, drill, and chisel attacks on the lock body. The Schlage L Series armor front is 1-1/4 inch by 8 inch and adjustable for door bevel.

Armor fronts are finish-specific and function-specific. The Schlage part 09-663 in 626 (satin chrome) finish covers the L9050, L9056, L9060, L9070, L9071, L9080, and L9082 functions. Part 09-666 covers a different configuration. Ordering an armor front without confirming the finish code and function produces a part that either does not fit or does not match the door hardware. Always pull both pieces of information from the installed hardware before ordering.

Spindle and Hub Assembly

The spindle is the square connecting rod that passes through the case and links the inside and outside levers. The hub is the internal component that connects the spindle to the case mechanism and holds the lever return springs. The lever return springs in the hub are sized to provide approximately 2 pounds of return force at the lever tip. When these springs fatigue, the lever droops below horizontal even with no other visible damage to the lock.

The Schlage L Series uses a security blocking hub that prevents gaining access to the lock mechanism by removing the levers. On locks where this is not a concern, a standard hub is fitted. Vandlgard versions use a hub with a clutch mechanism that allows the outside lever to rotate freely without engaging the mechanism when excessive torque is applied, preventing the forced-lever attack that can defeat a standard L Series lock in some configurations.

Mortise Cylinder and Cylinder Cam

The mortise cylinder screws into the case face and drives the deadbolt cam. The cylinder body is threaded at approximately 1.156 inch diameter with 32 threads per inch. Standard L Series cylinders include the Everest 29 S123 patented keyway in 6-pin conventional format. The cam is the component on the back of the cylinder that engages the deadbolt throw mechanism inside the case.

Cylinder cam replacement is one of the most frequently misunderstood service tasks on mortise locks. The cam must match both the cylinder type and the function. The Schlage L583-254 cam is used on standard conventional Schlage L Series mortise cylinders. The L583-446 cam is for Schlage modular mortise cylinders. The K510-730 cam is the standard cam for IC housings and works across Schlage IC configurations, Falcon non-deadbolt functions, and several other manufacturer applications. Using the wrong cam on a mortise cylinder produces a lock that either cannot throw the deadbolt or throws it only in one rotation direction.

Thumbturn Assembly

The thumbturn (T-turn) is the interior control that throws the deadbolt on applicable L Series functions. The Schlage part 09-509 T-turn fits doors from 1-3/8 inch to 1-7/8 inch thick with a rose diameter of approximately 1-3/4 inch. Thumbturn replacement is required when the thumbturn becomes stiff, when the internal cam connection wears and the turn no longer throws the deadbolt cleanly, or when the turn is damaged by abuse or attempted tampering. Always confirm door thickness before ordering a thumbturn replacement to ensure the correct depth is specified.

Lever Return Spring

The lever return spring (Schlage part L283-040 for the L Series) provides the return force that brings the lever back to horizontal after it is depressed. This is the highest-wear component in the L Series hub assembly and fails through fatigue on high-traffic doors. Lever sag is the primary symptom. The lever return spring is available individually and is far less expensive than replacing the full hub assembly. Replace the spring first before assuming the hub or spindle requires replacement.

Strike Plate

The L Series strike is the steel plate mortised into the door frame that receives the latchbolt and deadbolt. The standard L Series strike is a full-length plate matching the 8-inch armor front. Strike replacement is needed when the bolt pockets deform from extended high-traffic use, when the door has settled and the bolt pockets no longer align with the bolts, or when the frame is repaired and the original strike prep is modified. Always confirm whether the strike is a standard or a high-security box strike before ordering.

Falcon MA Series: The High-Traffic Value Mortise Lock

The Falcon MA Series is the Grade 1 mortise lock positioned below the Schlage L Series in price but at the same ANSI/BHMA Grade 1 certification level for both operational and security performance. It meets ANSI A156.13 Series 1000 Operational Grade 1 and Security Grade 1 with all standard trims and conventional mortise cylinders. It is UL listed for 3-hour fire doors under both UL 10B neutral pressure and UL 10C positive pressure testing, the same fire listing as the L Series.

Falcon MA Series Key Specifications

Falcon MA Series Spindle Breakaway

The Falcon MA Series uses independently mounted spindles designed to break away at a maximum of 480 inch-pounds of torque. This is the Falcon equivalent of the Schlage Vandlgard function: when someone applies excessive forced torque to the outside lever in an attempt to retract the latch or deadbolt, the spindle detaches from the chassis before that force reaches the internal mechanism. The chassis remains intact and functional. The spindle requires replacement after a breakaway event, but the chassis and all other components are preserved.

This matters for parts ordering. After a forced entry attempt on a Falcon MA Series installation where the door resisted entry, the spindle is likely broken or detached even if the door looks fine from the outside. Always check the spindle engagement when servicing an MA Series lock that has experienced a forced entry attempt. A loose or rattling lever with a firm chassis is the diagnostic sign of a broken spindle.

Falcon MA Series Cylinder Compatibility

The Falcon MA Series accepts cylinders from multiple sources. Conventional cylinders ship with the Falcon G keyway standard. SFIC (Small Format Interchangeable Core) cylinders are available in 6-pin or 7-pin configurations and accept Falcon SFIC cores as well as compatible cores from other manufacturers. Schlage Classic cylinders in C, E, and CE keyways operate the Falcon MA Series using the 5622-STD cam, which is a notable cross-brand compatibility feature that simplifies cylinder sourcing on projects where a Schlage key system is already in use.

The cylinder guard (parts A08790 and A08794) accommodates different cylinder lengths and door thicknesses. The correct cam must be specified based on the cylinder type and function. The factory supplies the correct cam when the function and door thickness are specified at order time. On field replacements, always confirm which cam is installed before ordering a replacement cylinder, as mismatching the cam to the cylinder produces a lock that operates in only one direction.

Falcon MA Series Functions

The Falcon MA Series uses a different function coding system from the Schlage L Series but covers similar ANSI function categories. Common functions include MA101 (passage), MA301 (privacy), MA381 (entrance), MA461 (classroom), and MA481 (storeroom). All function codes in the MA Series follow the pattern MA + function number + keyway/cylinder designation. When ordering replacement parts for the MA Series, confirm the MA function code from the label on the case body before selecting any chassis, latchbolt, or trim component.

Mortise Lock vs Cylindrical Lock: When Does Mortise Make Sense?

Mortise locks cost significantly more than cylindrical locks to purchase and install. They require a deeper and more complex door preparation. Parts are more function-specific and more expensive per component. Despite all of this, mortise locks are the correct specification in specific contexts where their advantages justify the cost.

Mortise locks are correctly specified on main building entries, secured office suites, healthcare patient area doors where tamper resistance is required, government facility doors, and any opening that justifies the higher purchase cost through extended service life. For interior corridor doors, storage rooms on lower-security floors, and any door where Grade 2 performance is sufficient, browse the cylindrical lock parts catalog for Schlage ALX Series or Falcon T Series alternatives that serve the application at lower cost.

How to Identify Your Mortise Lock Before Ordering Parts

The correct identification process for mortise lock parts ordering requires three pieces of information, all of which come from the installed hardware.

SecurityParts.com organizes both series in the mortise lock parts catalog by brand and series with interactive exploded diagrams on every model. For the complete Schlage hardware catalog including L Series, ND Series, and B Series deadbolts, browse the Schlage commercial hardware parts catalog. For Falcon hardware including MA Series mortise locks and T Series cylindrical locks, browse the Falcon commercial hardware parts catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Related Parts and Products at SecurityParts.com

Mortise locks are part of a complete commercial door opening. The main entry door that has an L Series mortise lock also has a door closer, often an electric strike or exit device, and sometimes alarm hardware on the same opening or building.

For Schlage B Series deadbolt parts on doors that use a separate deadbolt alongside a mortise lock on a secondary opening, browse the deadbolts catalog. For Schlage ND Series, ALX Series, and Falcon T Series cylindrical lock parts on interior doors in the same facility, browse the cylindrical locks catalog. For Von Duprin electric strike parts on access-controlled entries in the same building, browse the electric strikes catalog. For Von Duprin and Falcon exit device parts on egress doors in the same facility, browse the commercial exit devices catalog. For LCN door closer parts on any door in the facility with automatic closing hardware, browse the door closers catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex hardware in a single session.

SecurityParts.com carries parts for three commercial cylindrical lock series: the Schlage ND Series Grade 1 (24 mechanical functions, beyond-Grade-1 strength), the Schlage ALX Series Grade 2 (single modular chassis, field function change), and the Falcon T Series Grade 1 (extra heavy-duty, accepts any manufacturer's cylinder). The function code determines the correct chassis, spring cage, and trim components. Never order parts by appearance alone. The ND Series and ALX Series share lever styles for visual suiting but use different chassis and function kits. Parts that fail first are the spring cage, latch, and cylinder. Always confirm function code and manufacture date before ordering.

Commercial cylindrical locks are on more doors per building than any other lock category. Office corridors, storage rooms, restrooms, classrooms, patient rooms, server closets. Every one of those doors has a chassis, a latch, a spring cage, a cylinder, levers, and a strike. When one component wears or fails, replacing it correctly the first time depends entirely on having the right series and function code before you open any catalog page.

SecurityParts.com stocks parts for the three most widely installed commercial cylindrical lock series: the Schlage ND Series, the Schlage ALX Series, and the Falcon T Series. This guide covers every component, the function codes that determine which parts you need, what fails first, and how to order without a return. Browse the complete cylindrical lock parts catalog at SecurityParts.com for interactive diagrams on every model.

The Three Series at Security Parts: How They Compare

Schlage ND Series: Understanding Function Codes Before Ordering Parts

The ND Series function code is the most critical piece of information needed before any parts order. The function code determines the chassis configuration, the spring cage type, and which trim components are compatible. Ordering a spring cage or adjustment plate from the wrong function creates a non-functional lock even when the physical parts fit together.

The Most Common ND Series Functions in Commercial Buildings

Vandlgard: What It Is and Why It Matters for Parts Ordering

Vandlgard is a Schlage-patented feature that prevents forced lever torque from retracting the latch. On a standard ND Series lock, applying enough sustained downward force to the outside lever can, in some cases, retract the latch through the mechanical connection between the lever and the chassis. Vandlgard adds a clutch mechanism that breaks the lever-to-chassis connection before that force threshold is reached, while the lever can still operate normally when the door is unlocked.

Vandlgard function suffixes are ND91 (entrance/office), ND92 (entrance), ND94 (classroom), ND96 (storeroom), and ND97 (corridor). The Vandlgard function is field-selectable on the ALX Series, which means you can enable or disable it without ordering a different lock. On the ND Series, the Vandlgard feature is built into the function-specific chassis and cannot be retrofitted to a standard chassis without replacing the chassis assembly.

Most current institutional specifications for K-12, higher education, and healthcare require Vandlgard on classroom, storeroom, and secured office functions. If your building was originally specified with Vandlgard functions, all replacement parts must be sourced for the Vandlgard version of that function, not the standard version.

Every Replaceable Component in Commercial Cylindrical Locks

Chassis Assembly

The chassis is the internal mechanism housing that sits inside the door bore and contains the locking mechanism, the spindle engagement, and the spring return components. The chassis determines the function of the lock. It is not universal across functions on the ND Series. An ND50 chassis is configured differently from an ND70 or ND80 chassis, even though they look similar from the outside.

The Schlage ND Series chassis is zinc and steel with zinc dichromate plating for corrosion resistance. Door thickness accommodation is 1-3/4 inch standard with spacer kits available for 1-3/8 inch through 1-11/16 inch doors. The ALX Series uses a single chassis design that accommodates most functions, which is its key advantage for inventory management: one chassis type covers most of a building's lock schedule.

Replace the chassis when the internal mechanism fails to hold the locked state, when the spindle has developed severe play that cannot be addressed by spring cage replacement, or when a function conversion is required on the ALX Series. On the ND Series, function changes require a complete chassis replacement along with matching trim.

Spring Cage Assembly

The spring cage holds the lever in the horizontal position and provides the return force that brings the lever back after it is depressed. This is the most frequently replaced component on high-use cylindrical locks. Spring cage failure presents as lever sag, lever that does not return fully after being depressed, or a lever that rattles in the horizontal position.

Both Schlage ND and ALX Series use Grade 1 compression springs in the spring cage assembly specifically to resist lever droop under sustained use. The Falcon T Series uses a compression spring behind the cylinder that serves a similar function. When replacing a spring cage, confirm whether the outside or inside spring cage is failing before ordering. Both sides have their own spring cage assembly and they are not interchangeable with each other.

Latch Assembly

The latch is the spring-loaded bolt that extends from the door edge and clicks into the strike plate on the frame. On commercial cylindrical locks, the standard latch is a deadlatch, not a simple spring latch. A deadlatch has a plunger alongside the latch bolt that, when depressed by the strike plate on closing, prevents the latch bolt from being pushed back by a credit card or similar tool from the latch side of the door.

The Schlage ND Series default latch is part 13-247 with a 2-3/4 inch backset and 1-1/8 inch by 1-1/4 inch faceplate. The Falcon T Series default latch is part 23981145, a deadlatch with 2-3/4 inch backset and 1-1/8 inch by 2-1/4 inch square corner faceplate. Always confirm the backset (2-3/4 inch standard, 2-3/8 inch available) before ordering a latch replacement.

Latch failures on commercial cylindrical locks include the latch not retracting smoothly when the lever is depressed, the latch bolt not springing back after depression, and the deadlatch plunger binding or not depressing correctly. A latch that does not retract when the lever operates normally indicates the latch has failed, not the chassis. A latch that retracts but the lever feels stiff typically indicates the spring cage, not the latch.

Strike Plate

The standard ND Series strike is part 10-025, an ANSI curved lip strike, 1-1/4 inch by 4-7/8 inch, no box. The Falcon T Series default strike is part 5164, ANSI 1-1/4 inch by 4-7/8 inch with 1-3/16 inch lip length. The ALX Series uses the same ANSI curved lip strike as the ND Series.

Strike replacement is required when the strike is damaged by door misalignment, when the latch bolt fails to engage cleanly due to strike wear, or when a door handing change requires a different strike orientation. An ANSI box strike is used when hollow metal frame reinforcement is required. Always measure the existing frame cutout before ordering a strike replacement to confirm whether a standard or box strike fits the existing frame preparation.

Cylinders and Cylinder Formats

All three series at SecurityParts.com support multiple cylinder formats. Understanding the cylinder format installed is essential before ordering any cylinder replacement.

The Falcon T Series is specifically designed to accept cylinders from competing manufacturers including Sargent and Corbin Russwin in addition to Schlage. Some cylinders require modification of the lock for proper fit. Always specify the cylinder manufacturer when ordering a T Series with a non-standard cylinder.

Levers, Roses, and Trim

Levers on the ND Series are available in 9 designs including Athens, Rhodes, Sparta, Saturn, Broadway, Latitude, and Omega styles. The ALX Series shares these same lever designs, which is the visual suiting feature that allows mixed Grade 1/Grade 2 buildings to maintain a consistent appearance. Levers are pressure cast zinc finished to match mating parts.

The rose is the circular cover plate that conceals the chassis bore and the mounting screws on each side of the door. The ND Series rose is 3-7/16 inch standard diameter. The ALX Series rose is 3-7/16 inch standard, matching the ND Series for a seamless appearance when both are installed in the same building.

On the ALX Series, an optional break-away feature is available on Rhodes levers for most locking functions. When excessive torque is applied, the handheld portion of the lever breaks away from the shank, protecting the internal chassis from the torque damage that would otherwise require chassis replacement. This is a documented X Factor feature of the ALX Series and worth specifying on doors that receive frequent abuse.

Schlage ALX Series: The Modular Advantage and What It Means for Parts

The ALX Series modular design is the most significant feature for facilities managers and locksmiths who maintain large building inventories. A single chassis type supports most functions and all cylinder applications. This means a building can stock one chassis type and change functions in the field when a room's use changes, rather than ordering a new configured lock for every function change.

How In-Field Function Change Works

The ALX Series function is determined by a separate function kit that drops into the chassis. Changing from an ALX50 office function to an ALX70 classroom function requires the ALX70 function kit, not a new lock. The chassis stays. The lever stays. Only the function kit changes. This approach reduces inventory carrying costs, eliminates lead time waiting for factory-configured stock, and lets locksmiths carry a small number of kits on their truck rather than multiple configured lock units.

The installation sequence is designed for this: drop in the interior lever, install the function into the chassis, place the chassis in the door bore with the outside lever on the spindle, drop in the latch, drop in the cylinder or exterior function part. The separate compartment packaging keeps parts organized and prevents the small-part loss that often delays field service calls.

Captured Screws

The ALX Series uses captured screws in the latch, strike, and inside spring cage. Captured screws are retained in the component and do not fall out when the component is removed from the door. This eliminates the most common cause of rework on cylindrical lock service calls: small screws falling into wall cavities or onto floors during disassembly. On a building with dozens or hundreds of locks being serviced in a single shift, this feature has a real cumulative impact on service time.

Falcon T Series: The Multi-Cylinder Advantage and Pressure Release

The Falcon T Series occupies a distinct position in the cylindrical lock market. It is Grade 1 extra heavy-duty, designed for the highest-abuse institutional applications including government and military facilities, correctional housing, and any environment where locks receive deliberate physical attack rather than normal use.

Pressure Release Lever Rotation

The Falcon T Series includes Pressure Release lever rotation as a standard feature. When excessive torque is applied to the outside lever beyond the normal operating range, the lever rotates to a stop position that breaks the mechanical connection to the chassis rather than transmitting that force into the internal mechanism. This prevents the internal chassis damage that requires replacement after a forced entry attempt. The Pressure Release mechanism returns to normal operation after the excessive force is removed, without requiring any parts replacement, which is what makes it a standard feature rather than a consumable component.

Universal Cylinder Acceptance

The Falcon T Series is designed and marketed specifically on its ability to accept cylinders from competing manufacturers. In retrofit applications, this means a facility with an existing Corbin Russwin or Sargent key system can install T Series locks and retain their existing key system without rekeying. The T Series ships with 6-pin chambers drilled in 5-pin configuration as standard. 6-pin pinning is available at no extra cost when specified at ordering. This cylinder flexibility is the primary reason the T Series is specified on government and military retrofit projects where key system continuity is a security requirement.

Parts That Fail First: Realistic Replacement Frequency

Here is the actual field replacement order across all three series based on service call frequency.

1. Spring cage assembly. The most common replacement item on cylindrical locks with more than five years of high-traffic use. Lever sag, incomplete lever return, and lever rattle all trace to spring cage fatigue. Always try spring cage replacement before ordering a chassis.

2. Latch assembly. Latch bolts wear at the tip from repeated contact with strike plates that are slightly misaligned. The deadlatch plunger binding is a specific failure mode on latches that have been in service for more than 10 years without lubrication. Latches are inexpensive individual components and should be replaced rather than lubricated repeatedly once wear is visible on the bolt tip.

3. Cylinder. Cylinders wear from key insertion, especially in high-traffic entry doors. Signs of cylinder wear include a key that operates stiffly, a key that only works in one rotational direction, or a cylinder that spins without retracting the latch. FSIC and SFIC cylinders in interchangeable core systems can be replaced in seconds without disassembling the lock. Conventional cylinders require pulling the lock for cylinder removal.

4. Lever assembly. Levers bend, crack, or have their finish worn off from high-contact use. Lever replacement is cosmetic when the lock function is not impaired. Lever replacement is functional when a bent lever fails to return to horizontal or fails to fully depress the chassis mechanism on operation.

5. Strike plate. Strike wear accelerates when the door has settled and the latch bolt contacts the strike lip rather than entering the pocket cleanly. A worn or deformed strike allows a door that feels locked to actually be holdable open with sustained pressure. Strike replacement is inexpensive and should be done proactively when door alignment has been corrected.

How to Identify Your Lock Model Before Ordering

The model label is on the chassis body, visible when the inside lever and rose are removed. The label shows the series designation (ND Series, ALX Series, T Series), the function code (ND70, ALX50, T581), the finish code (626, 622, 619), and the handing if the lock is handed. For Schlage ND Series, the manufacture date is also on this label and is critical for selecting the correct parts revision.

If the label is worn or missing on an older ND Series unit, the function can often be determined by testing: the way the inside and outside levers behave without a key present tells you the function. A lever that is always free on one side and always locked on the other is storeroom (ND80). A lever that locks with a button from inside is entrance/office (ND50). A lever that locks from the outside with a key but the inside is always free is classroom (ND70).

For Falcon T Series locks, the model is stamped or cast into the chassis body itself. Common T Series model codes include T501 (passage), T521 (privacy), T561 (storeroom), T571 (classroom), and T581 (entrance/office).

SecurityParts.com organizes all three series in the cylindrical locks parts catalog by brand and model with interactive exploded diagrams. For Schlage commercial hardware parts including the ND Series, ALX Series, and Schlage B Series deadbolts, browse the Schlage catalog. For Falcon commercial hardware parts including the T Series and Falcon exit devices, browse the Falcon catalog. Pre-order support is available at 845-935-0301 or through the contact page.

Related Parts and Products at SecurityParts.com

Cylindrical locks are part of a complete commercial door opening. The complete assembly on most institutional doors also includes a door closer, exit device, or mortise lock at higher-security openings.

For Schlage L Series and Falcon MA Series mortise lock parts on high-security and main entry doors in the same facility, browse the mortise locks catalog. For Schlage B Series deadbolt parts on doors that use a deadbolt alongside a cylindrical lock, browse the deadbolts catalog. For LCN door closer parts on any door with automatic closing hardware, browse the door closers catalog. For Von Duprin and Falcon exit device parts on egress doors in the same building, browse the commercial exit devices catalog. For Von Duprin electric strike parts on access-controlled entries, browse the electric strikes catalog.

Browse the complete all products and parts catalog to source Schlage, Falcon, Von Duprin, LCN, and Detex in a single session.

Von Duprin electric strikes replace the fixed strike plate on a door frame and allow remote unlocking via access control. The 5100 is medium-duty, the 6100 and 6200 are heavy-duty stainless steel, and the 6300 is a fire-rated no-cut surface-mounted rim strike. Parts that fail most often are the solenoid assembly, the keeper, and the faceplate. Solenoid kits are voltage-specific: part 050237 for 12VDC, part 050240 for 24VDC. Always confirm wire color before ordering a replacement solenoid: black wires mean 24VDC, yellow wires mean 12VDC. Getting this wrong destroys the solenoid immediately.

Electric strikes are the most widely replaced access control hardware component in commercial buildings. Unlike mechanical strike plates, which are passive, an electric strike has a moving keeper, a solenoid, a spring, and electrical connections that all wear, corrode, and fail over time. The Von Duprin electric strike series is the most common in institutional and commercial buildings across North America, installed alongside Von Duprin and Falcon exit devices on virtually every category of egress door.

When one fails, you need the right part fast. A failed electric strike on a secured entry either leaves a door that cannot be locked or a door that cannot be opened from a credential. Both are problems that shut down operations. This guide covers every series, every replaceable component, the fail safe vs fail secure distinction that creates the most field confusion, and the exact diagnostic steps that identify the failed component before you order anything. Browse the complete Von Duprin electric strikes parts catalog at SecurityParts.com for model-specific diagrams on every series.

How Von Duprin Electric Strikes Work

A standard mechanical strike plate is fixed. The latch bolt from the door lock clicks into it and stays. An electric strike replaces that fixed plate with a mechanism that includes a movable keeper, called the lip or gate. When the door is closed, the keeper is rigid and holds the latch bolt securely. When an authorized credential or button press energizes the solenoid, the keeper pivots and allows the latch bolt to pass through, letting the door open without anyone touching the lock on the door.

This is the design advantage over fully electrified locksets. The mechanical lock on the door stays completely unchanged. The electric strike handles the access control function at the frame. You can retrofit access control onto existing doors with mechanical locks without replacing the lock itself, which is significantly less expensive and less invasive.

The solenoid is the electrical component that drives the keeper. When powered, it either locks or unlocks the keeper depending on the fail mode configuration. The solenoid connects to an access control panel output relay, a door release button, or a credential reader. The electrical connection is low voltage, typically 12VDC or 24VDC DC, and the wire run from the panel to the frame is carried through the wall or concealed in the frame cavity.

The Four Active Von Duprin Electric Strike Series

Fail Safe vs Fail Secure: The Most Important Decision Before You Order

This is the distinction that causes more wrong-part orders and post-installation failures on electric strikes than any other single factor. Getting it backwards means the door either cannot be secured or cannot be exited, depending on which way it is wrong.

Fail Safe (FS): Unlocks When Power is Lost

In a fail safe configuration, the strike is continuously powered to stay locked during normal operation. When power is cut, whether from a power outage, a tripped breaker, or a fire alarm activation, the solenoid releases and the keeper becomes free. The door can be pushed open without any credential. This is the required configuration for any fire-rated egress door where free exit must be maintained at all times, including during a power failure. It is also required for egress paths covered by IBC Chapter 10 where electronic locking is permitted only if the lock releases on fire alarm.

Fail Secure (FSE): Stays Locked When Power is Lost

In a fail secure configuration, the strike is energized only momentarily to unlock. During a power failure, the keeper remains rigid and the door cannot be opened without a credential. This is the correct configuration for server rooms, exterior building entries, secure storage areas, and any location where security must be maintained even during a power outage. The Von Duprin 6300 Series is fail secure only, which is required to achieve its UL 10C fire door rating.

How to Identify the Fail Mode on an Installed Strike

There is a reliable field test that works on any installed electric strike. Remove power from the strike. Try to open the door by pressing or pulling the exit device. If the door opens without power, the strike is fail safe. If the door stays locked without power, the strike is fail secure. This takes 30 seconds and eliminates any ambiguity from worn or missing labels on the hardware.

For Von Duprin 6100 and 6200 series units, the fail mode can be field-converted between fail safe and fail secure by repositioning the actuator inside the strike body without replacing the solenoid. The 050237 (12VDC) and 050240 (24VDC) solenoid kits are field-selectable between both modes. This conversion capability is one of the most valuable features of the 6000 Series and is documented in the service manual diagrams available on the SecurityParts.com model pages.

Every Replaceable Component in Von Duprin Electric Strikes

Solenoid Assembly: The Most Commonly Replaced Component

The solenoid is the electromagnetic coil that converts electrical current into the mechanical movement that drives the keeper. It is the component under the most electrical and thermal stress in normal operation and the one that fails most often in high-use installations.

Von Duprin 6000 Series solenoid kits are voltage-specific. This is the single most important detail in electric strike parts ordering.

Box Assembly

The box assembly is the metal housing that mounts in the door frame cutout and contains the solenoid, keeper spring, and electrical components. Von Duprin 6100 and 6200 series strikes use several box assembly types depending on the frame configuration and application.

Type A Box: Standard box assembly for typical hollow metal frame applications. The most common configuration.

Type B Box: Used on 6200 series mortise and cylindrical applications with specific frame geometry requirements. Type B Box images in the parts manual confirm the installation orientation.

Type C Box: Used on 6100 and 6200 series applications requiring a different frame depth. Available in DS (door status) and DS-LC (door status with latch check) versions that add monitoring capability to the box assembly without a separate monitor switch.

Offset Box: For frame applications where the standard solenoid position creates a conflict with the frame construction. The offset box repositions the solenoid 90 degrees from the standard orientation.

Faceplate Package

The faceplate is the visible plate on the frame face that covers the strike body and presents the keeper opening. Von Duprin 5100 series faceplate packages are available in three configurations.

Part 050031: Standard 4-7/8 inch faceplate package for typical commercial frame applications.

Part 050032: Round corner 4-7/8 inch faceplate for frames with rounded corners or decorative trim.

Part 050033: Long 7-11/16 inch faceplate for applications requiring extended coverage of the frame face.

Faceplate packages include the faceplate, wire nuts, and all fasteners required for installation. Always specify the finish when ordering, as faceplates are available in multiple finishes and the finish code is required for the correct part.

Keeper (Strike Lip)

The keeper, also called the strike lip or gate, is the moving component that holds the latch bolt when locked and releases when the solenoid is activated. The keeper takes direct mechanical contact from the latch bolt on every door close, which makes it a wear component on high-traffic openings. The correct keeper for each 6200 series model varies because the lip design differs between cylindrical and mortise applications. Always confirm the exact strike model when ordering a keeper replacement.

A keeper with visible wear marks, deformation, or a loose pivot shows up as inconsistent latching or a door that does not feel firmly latched even when the access control system shows it as locked. Replacing the keeper alone is significantly less expensive than replacing the full strike assembly when the box and solenoid are still functional.

Screw Package and Mounting Package

Screw Package (PKGSCR.1003 for US32D finish, PKGSCR.1004 for black finish): Includes the #10-24 5/16 inch UFPHMS, 12-24 1/2 inch UFPHMS, 12-14 1 inch UFPHWS, and blue wire nut. Required when reinstalling a strike with damaged or missing original hardware.

Mounting Package (PKGMTG.1004 for US32D, PKGMTG.1005 for black): Includes the mounting tab zinc, mounting tab shim nylon, and 10-24 1/2 inch UFPHMS. The mounting tab allows the strike to be positioned horizontally in the frame cutout for precise latch alignment.

Solenoid Washer and Solenoid Spring

Part 964037 Solenoid Washer: Seats the solenoid in the box assembly and ensures proper alignment of the plunger. A missing or damaged washer causes solenoid misalignment that results in incomplete keeper movement even when the solenoid itself is functional.

Part 968713 Solenoid Spring: Returns the plunger to its resting position after each activation cycle. Spring fatigue is a legitimate failure mode on doors that are released hundreds of times per day. Symptoms include a keeper that activates correctly but returns slowly or incompletely to the locked position, creating a security gap on fail secure applications.

The 6300 Series: What Makes It Different and When to Use It

The 6300 is the only Von Duprin electric strike that requires no frame cutting. Every other series in the Von Duprin lineup requires cutting or modifying the door frame to recess the strike body. The 6300 mounts surface on the frame stop face, which makes it the correct specification in three specific situations where no other series works.

When the 6300 Is the Right Choice

Aluminum storefront retrofit: Aluminum storefronts have thermal breaks inside the frame profile. Cutting into the frame to recess a strike destroys the thermal break and compromises the building envelope. The 6300 mounts on the frame face without cutting, preserving the thermal break.

Historic preservation projects: Frame modification is not permitted on many historic building projects. The 6300 provides electrified access control without permanent modification to the original frame.

Tenant fit-out on leased space: When a tenant cannot modify the building structure, the 6300 delivers access control capability that can be removed at lease end without leaving a frame cutout.

6300 Key Specifications

The 6300 is fail secure only. It achieves UL 10C 3-hour fire door rating in the fail secure mode. UL 1034 burglary-resistant and UL 294 access control system listed. Static strength is 1500 lbs. Dynamic strength is 70 ft-lbs. Compatible with 12VDC or 24VDC using the plug-in voltage connectors shipped with the unit. Two voltage connectors ship in the package and only the correct one for the available system voltage is used.

6300 Exit Device Compatibility

The 6300 works with a broad range of rim exit devices. Von Duprin compatibility includes the 22/22-F Rim, 33A/35A Rim, 55 Rim, 88/88-F Rim, and 98/99/98-F/99-F Rim. Falcon compatibility includes the 19/19-F Rim, 24/24-F Rim, and 25/25-F Rim. The entry buzzer accessory (part 050242, for fail secure applications) is also compatible with the 6300 and is wired in parallel with the circuit to sound an audible alert when the strike is unlocked remotely.

Troubleshooting Von Duprin Electric Strike Problems

Before ordering any replacement part, run this diagnostic sequence. Half of all reported electric strike failures are not component failures at all. They are power delivery problems, wiring issues, or latch alignment problems that require no parts whatsoever.

Entry Buzzer and AC Rectifier Accessories

Two accessories for the Von Duprin electric strike series are commonly missing from parts orders because they are rarely described in detail anywhere.

Entry Buzzer (Part 050242)

The entry buzzer is available for fail secure strike applications only. It mounts in the door frame and wires in parallel with the strike circuit. When the strike is energized to unlock (in a fail secure configuration, this is when the door is being released for entry), the buzzer sounds an audible alert to notify the person inside that someone is requesting entry. This is the standard specification for any secured entry point where the occupant should be aware of remote unlock events. The buzzer is not compatible with fail safe strikes because in fail safe, the strike is powered continuously and the buzzer would sound constantly.

AC Rectifier Kits (SO12 and SO24)

Von Duprin electric strike solenoids are DC devices. Some access control panels and power supplies output AC rather than DC. The SO12 kit converts 12VAC to 12VDC for the strike solenoid. The SO24 kit converts 24VAC to 24VDC. These kits are field-installable and plug in-line to the solenoid wiring. If a newly installed strike chatters, hums, or activates erratically despite correct voltage at the terminals, the panel may be outputting AC to a DC solenoid. The SO12 or SO24 rectifier kit is the correct fix, not a solenoid replacement.

How to Order Von Duprin Electric Strike Parts Without a Return

Three pieces of information are required before any electric strike parts order.

1. The exact series and model number. The model number is stamped or labeled on the faceplate or on the box housing. Von Duprin 4200, 5100, 6100, 6200, 6300, and 6400 series all use different part numbers for components with the same name. A solenoid kit for the 5100 series (part 050034) is completely different from the 6000 series kit (050237 or 050240). Order by series designation, not by component name.

2. The system voltage. Confirm whether the access control panel outputs 12VDC or 24VDC at the lock output. This determines whether you order the 050237 (12VDC) or 050240 (24VDC) solenoid kit. If uncertain, measure with a multimeter during an access grant signal before ordering.

3. The fail mode. Confirm fail safe or fail secure before ordering any solenoid, box assembly, or complete strike. Solenoid parts for fail safe and fail secure configurations on the same series are not always interchangeable. The 6100 and 6200 series field-selectable kits cover both modes with the same part number, but the 6300 is fail secure only and no conversion is available.

SecurityParts.com organizes the complete Von Duprin electric strikes parts catalog by series with interactive exploded diagrams. You confirm the exact component visually before ordering. Pre-order support is available at 845-935-0301 or through the contact page.

Related Parts and Products at SecurityParts.com

Von Duprin electric strikes are always part of a larger door opening assembly. The complete opening typically includes an exit device, a door closer, and sometimes a cylindrical or mortise lock on the same door.

For Von Duprin and Falcon exit device parts on the same door, browse the commercial exit devices catalog. The electric strike and exit device on a rim-style opening must be matched for latch bolt geometry and throw depth. For Von Duprin parts by series including the 98/99, 22, 33/35A, 75, 88, and Guard-X, browse the Von Duprin brand catalog. For LCN door closer parts on the same commercial door, browse the door closers catalog. For Schlage L Series and Falcon MA Series mortise lock parts on high-security doors in the same facility, browse the mortise locks catalog. For Von Duprin Guard-X and Detex exit alarm parts on secondary exits, browse the exit alarms catalog.

Browse the complete all products and parts catalog to source across all brands in a single session.

LCN door closers use a rack-and-pinion mechanism with hydraulic fluid to control closing speed. The 4040XP is the institutional flagship with cast-iron cylinder, forged steel arm, Liquid X all-weather fluid, Green Dial spring sizing (1 through 6, ships at size 3), and four adjustment valves. Arms are model-specific and not interchangeable between series. A leaking cylinder cannot be refilled in the field. If the sweep valve is fully open and the door still slams, replace the cylinder assembly. Always use the model number stamped on the body, not the body's physical appearance, to identify the correct replacement part.

LCN has manufactured commercial door closers since 1877. Walk through any school, hospital, government building, or office in North America and you will almost certainly pass an LCN closer. They are on more institutional doors than any competing brand, which also means they generate more field service calls than any competing brand.

Most of those service calls come down to the same handful of failures. Hydraulic leaks. Stripped spindles. Broken or bent arms. Valves that no longer hold their settings. Getting the right replacement part fast without a wrong-part return is what determines whether the door is back in service today or next week. This guide covers the complete LCN door closer parts catalog at the field level, starting with what actually fails and ending with how to order correctly.

How LCN Door Closers Work

Every LCN surface-mounted closer operates on the same fundamental principle: a coil spring stores energy when the door opens and releases it to close the door, while hydraulic fluid flowing through calibrated valves controls the speed of that release. Inside the cast-iron body, a rack gear acts as a piston. The pinion shaft connects the rack to the arm outside. When you open the door, the arm rotates the pinion, which drives the rack against the spring. Hydraulic fluid is displaced from one side of the rack to the other through small internal channels with adjustable valve screws.

This is the mechanism that every valve adjustment interacts with. The sweep valve controls how fast fluid moves during the main arc. The latch valve controls the final 10 to 15 degrees. The backcheck valve restricts fluid movement when the door is pushed open hard, creating resistance that protects walls and hardware. None of these valves add or remove force. They only regulate the speed of fluid transfer. If the fluid is gone, no valve setting can correct a slamming or drifting door.

LCN fills every 4040XP with Liquid X all-weather hydraulic fluid, which maintains consistent viscosity from -30 degrees F to 120 degrees F for manual closers. This temperature stability is why the 4040XP performs correctly on exterior doors and vestibules where temperature swings are significant. Standard hydraulic fluid thins in summer heat and causes uncontrolled fast closing on exterior applications.

LCN Series Carried at SecurityParts.com

SecurityParts.com stocks replacement parts and interactive diagrams for every major LCN series currently in commercial service. Understanding which series is installed is the first step before any parts order. Browse the full LCN parts catalog to navigate by series.

The LCN 4040XP: Every Component Explained

Cylinder Assembly (4040XP-3071)

The cylinder is the heart of the 4040XP. It contains the spring, rack gear, pinion shaft, bearings, and all hydraulic fluid passages. LCN uses a high-strength cast-iron body with a 1.5-inch diameter piston. The pinion shaft on the 4040XP measures 3/4 inch in diameter, which is larger than the original 4040, giving 44 percent more bearing load capacity. This enlarged shaft is the main structural improvement of the XP designation.

When the cylinder leaks, the entire assembly must be replaced. LCN does not supply rebuild seals for field refilling. Trying to top up hydraulic fluid in a leaking 4040XP body does not restore function because the seal that failed will continue to fail. The correct repair is ordering a replacement cylinder assembly (part 4040XP-3071) matched to the finish code on the existing unit.

Arm Assembly and Arm Configurations

The arm connects the closer body to the door or frame and is the component most likely to be physically damaged in service. LCN produces several arm configurations for the 4040XP. Choosing the wrong configuration for the mounting position is the most common installation error in the field.

The Green Dial Spring Power System

The LCN Green Dial is a patented visual indicator on the spring tube that shows the current spring power setting from size 1 through size 6. The 4040XP ships set to size 3, which provides adequate closing force for a standard 36-inch interior door in a regular arm configuration. Adjust with the 5/32-inch hex screw on the spring tube: clockwise increases spring power, counterclockwise decreases it.

Spring sizing is not guesswork. LCN publishes a sizing chart based on door width and mounting configuration. For interior doors up to 36 inches, size 3 is the starting point. For exterior doors from 36 to 48 inches, size 4 to 5. For exterior doors over 48 inches or high wind exposure locations, size 5 to 6. After setting the spring size, always verify ADA compliance with a calibrated force gauge. The dial setting is a starting point, not a guarantee of the actual force measured at the door face because door weight, hinge friction, weather seal drag, and threshold resistance all affect the actual opening force independently of the spring setting.

The Four Valve Adjustments

The 4040XP has four adjustment screws on the face of the closer body, labeled for identification. Each controls a different phase of the door's movement. Use a 3/32-inch hex key for the sweep and latch valves. Use the 5/32-inch hex key for the spring power screw. Turn clockwise to decrease speed (slow down), counterclockwise to increase speed.

Cover Plate (4040XP-72 and 4040XP-72-MC)

The 4040XP ships with a snap-fit non-handed plastic cover (part 4040XP-72) that protects the cylinder body and presents a clean finished appearance. The metal cover (part 4040XP-72-MC) is an optional upgrade for applications where the plastic cover is subject to physical abuse or where a more durable appearance is required. The snap-fit retention design on the current 4040XP cover is an improvement over earlier designs that required fasteners at each end.

Drop Plates and Mounting Brackets

Drop plates offset the closer body from the standard mounting position to accommodate non-standard door frame geometry, flush ceiling conditions, or narrow top rails that prevent direct mounting. LCN produces several drop plate configurations for the 4040XP. The 4040XP-18PA is the parallel arm drop plate. The 4040XP-18TJ is the top jamb push-side drop plate, which permits 120-degree maximum opening. Specifying the wrong drop plate or omitting one that is actually required causes arm binding, uneven door travel, and accelerated wear on the spindle.

Spindle and Bearing Assembly

The spindle connects the arm to the pinion shaft inside the cylinder body. The 4040XP uses full complement low-friction bearings to distribute load evenly across the full bearing race. Spindle wear produces a loose, rattling arm with noticeable play when the door is opened manually. Continuing to operate a closer with a worn spindle puts progressively increasing side load on the cylinder body, which accelerates wear and can eventually damage the housing threads. Spindle replacement is available without replacing the full cylinder assembly.

LCN Concealed Closers: 2030, 3030 and 3130 Series Parts

Concealed closers are specified when surface hardware is architecturally unacceptable. The body mounts inside the door frame transom or within the door top rail, making the hardware invisible when the door is closed. These are the closers found in hotel lobbies, high-end office building entrances, healthcare reception areas, and government buildings where the aesthetic standard prohibits visible surface hardware.

LCN 2030 / 5030 / 6030 Series

The 2030 Series is LCN's heavy-duty concealed closer for high-traffic applications. The body conceals in the frame transom and the arm track conceals in the door top rail, making all hardware invisible from both sides of the door. The 5010 variant conceals only the body in the frame while using an exposed double-lever arm. The 6030 is sized for heavy doors in demanding institutional environments. Parts include the track assembly, track roller, cylinder assembly, and mounting package. Track rollers on the 2030 series are among the most frequently replaced components because they take direct mechanical contact on every door cycle.

LCN 3030 / 3130 Series

The 3030 uses an exposed double-lever arm with the body concealed in the frame transom. The 3130 adds a concealed single-lever arm with a low-friction track and roller assembly, minimizing visible hardware even further. Both carry ANSI/BHMA A156.4 Grade 1 ratings. Parts for the 3130 include the track roller assembly (part 3130-3034H), cylinder assembly, and arm components. The track roller on the 3130 is a wear item on high-traffic doors and should be inspected during annual fire door maintenance.

LCN Sentronic Electromagnetic Hold-Open Closers

The 3130SE, 4040SE, 4310ME, and 4410ME Sentronic series integrate an electromagnetic hold-open coil that connects to the building's fire alarm system. During normal operation, the electromagnetic coil holds the door open. When the fire alarm activates, power is interrupted, the coil releases, and the spring drives the door closed. This is the correct specification under NFPA 80 Section 6.6.1 for fire and smoke barrier doors that must remain open during occupied hours but close automatically on alarm activation. Parts include the magnet assembly (SEM 7800 Series), coil components, and the closer cylinder assembly specific to each Sentronic model.

Parts That Fail First on LCN Closers: A Realistic Ranking

After 30-plus years of supplying commercial door hardware parts, we know the actual failure sequence. Here is what breaks, in the order it breaks.

1. Hydraulic cylinder seals: The most common LCN failure in the field. Oil visible on the door frame or floor confirms seal failure. The cylinder must be replaced as a unit. No field repair. No refill. Order the replacement cylinder matched to your model number and finish.

2. Arm assembly: Arms crack, bend, or strip their spindle connection on high-abuse applications. A bent arm causes uneven door travel and rapidly accelerates spindle wear in the cylinder body. Replace the arm before the cylinder sustains secondary damage. Always match the arm suffix to the exact model on the closer body.

3. Spring tension loss: After 10 or more years of continuous use in high-traffic locations, the coil spring loses tension and the door fails to latch consistently. The Green Dial can compensate for minor tension loss, but cannot overcome a spring that has lost its mechanical memory. Cylinder replacement is the correct resolution.

4. Spindle and bearing wear: Produces noticeable arm play and a loose, rattling door. Most common in correctional, healthcare, and educational environments where doors are opened hard repeatedly. Replace before the side loading damages the cylinder body threads.

5. Cover plate damage: Cracks or breaks from deliberate abuse or cart impact on corridor doors. The plastic cover (4040XP-72) is available individually. In high-abuse settings, upgrade to the metal cover (4040XP-72-MC) on replacement.

6. Drop plate and shoe fastener failure: Loose mounting screws cause arm play that looks like spindle wear. Check and tighten all mounting fasteners before ordering spindle components.

How to Identify Your LCN Closer Model Before Ordering Parts

The model number is the only reliable identifier for ordering LCN replacement parts. Physical appearance is not sufficient because multiple LCN series look nearly identical from the outside but use different internal components, different arms, and different mounting hardware.

Remove the cover plate (two fasteners at the ends of the cover on most models). The model and finish code are on a sticker attached to the cylinder body. The model number format is typically: series designation, suffix code, and finish code. For example, 4040XP-3077-689 identifies a 4040XP series with a standard regular arm and aluminum finish.

For older units where the sticker has worn off, measure the horizontal center-to-center hole distance on the closer body. LCN body sizes are standardized across production runs, and those dimensions can narrow the identification to a small number of candidates. If the body casting shows numbers like "71" or "320G," those are internal casting marks, not model numbers. They identify the production run, not the series. Always use the sticker model number for parts ordering.

LCN Door Closer Adjustment: Step-by-Step

Proper adjustment prevents the most common LCN service calls and extends cylinder life. Follow this sequence for any new installation or post-repair adjustment.

Step 1: Set All Valves to a Known Baseline

Turn all adjustment valves clockwise until they seat gently. Do not overtighten. The valve seats are brass and will strip. From fully closed, open each valve 1.5 turns counterclockwise. This is the approximate factory starting position.

Step 2: Set Spring Power with the Green Dial

Use LCN's sizing chart to determine the correct spring size for the door width, door weight, and mounting configuration. Set the Green Dial to that position. For parallel arm mounting, add one size. Check the actual opening force with a calibrated force gauge if ADA compliance is required. 5 pounds maximum is the ADA threshold for interior non-fire-rated doors.

Step 3: Set Sweep Speed

Open the door to 90 degrees and time the closing arc from 90 degrees to within 3 inches of the latch. ADA requires a minimum of 5 seconds. Adjust the sweep valve in 1/8-turn increments until the timing is correct. Test at least three consecutive closes to confirm consistency.

Step 4: Set Latch Speed

Watch the final 10 to 15 degrees before the door closes. The latch should engage cleanly with a firm click, not a slam. If the door stops short of latching, open the latch valve slightly. If it slams in the final arc, close the latch valve slightly. On fire-rated doors, positive latching on every close is a NFPA 80 compliance requirement, not a preference.

Step 5: Set Backcheck

Open the door quickly past 70 degrees and feel for resistance. Backcheck should provide a cushioning effect that prevents the door from slamming into a wall, but should not prevent full opening. If backcheck engages before 70 degrees and restricts normal door use, open the backcheck valve slightly. If there is no backcheck at all and the door swings freely to 180 degrees, close the backcheck valve clockwise until resistance is felt at 70 to 75 degrees of opening.

LCN Sentronic and Fire Door Applications

LCN Sentronic electromagnetic hold-open closers are the correct specification for any fire or smoke barrier door that must remain open during normal building operations. They are not optional convenience items. NFPA 80 Section 6.6.1 specifies that a fire door held open by any device must be connected to the building fire alarm system so it closes automatically on alarm activation.

Using a mechanical wedge, a rubber doorstop, or any manual hold-open device on a fire-rated door is a NFPA 80 violation that creates both a code compliance issue and a liability exposure. The Sentronic series eliminates this problem by integrating the hold-open function into a UL-listed fire door hardware assembly that responds automatically to the fire alarm system.

Parts for Sentronic series closers include the SEM 7800 Series magnet assemblies, the electromagnetic coil components, and the closer cylinder assembly. Browse the full door closers parts catalog for all Sentronic series diagrams and components.

Related Parts and Products at SecurityParts.com

LCN door closers are part of a complete door hardware assembly. A full service call on an institutional door typically involves the closer, the exit device, and sometimes an electric strike or lock hardware on the same opening.

For Von Duprin and Falcon exit device parts on the same door, browse the commercial exit devices catalog by brand and series. For Von Duprin electric strike parts including 5100, 6100, 6200, and 6300 series, browse the electric strikes catalog. For mortise lock parts on high-security doors in the same facility, browse the mortise locks catalog. For Von Duprin Guard-X exit alarm parts on secondary exits, browse the exit alarms catalog. For Schlage and Falcon cylindrical lock parts on interior office and corridor doors, browse the cylindrical locks catalog.

Browse the complete all products and parts catalog to source Von Duprin, LCN, Schlage, Falcon, and Detex in a single session, or reach the team at 845-935-0301 for pre-order compatibility support.

The Von Duprin 98/99 series is on more institutional doors than any other exit device in North America. Schools, hospitals, government buildings, universities, airports. If you manage a commercial facility or work as a locksmith, you will service this device more than any other in the Von Duprin lineup.

This guide covers everything you need to work on 98/99 series exit device parts efficiently. It covers the configurations, the parts that fail, the dogging details that trip people up, the electrified options, and exactly how to order the right component without a return. Browse the full Von Duprin parts catalog at SecurityParts.com for model-specific diagrams on every series.

What Makes the 98/99 Series Different From Other Von Duprin Devices

The 98/99 sits at the top of the Von Duprin lineup. It is the deepest specification in terms of electrified options, the most configurable in terms of device type, and the only Von Duprin series that carries full Made in USA production. ANSI/BHMA A156.3 Grade 1 certification means it is tested to the highest cycle and force standards in the exit device category.

The case distinction is simple: the 98 series has a smooth mechanism case and the 99 series has a grooved case. Both are mechanically identical. The grooved case on the 99 gives a better grip surface under repeated push pad contact, which is why healthcare and institutional specifications often call for the 99 specifically.

The forward compatibility advantage is what separates the 98/99 from every other series. A mechanical device installed today can be converted to QEL quiet electric latch retraction, MEL motorized retraction, Chexit delayed egress, Allegion Connect, or other access control options years later without replacing the device body. Facilities managers doing phased access control upgrades depend on this.

98/99 Series Configurations: Which One Fits Your Door

Rim Device (98, 99, F-98, F-99)

The rim device mounts on the door face and latches at a single frame-side strike. Standard for single doors and paired doors with a center mullion. The F-prefix versions (F-98, F-99) are fire exit hardware with a UL fire listing. They must positively latch on every door close and do not support hex dogging. The standard 98/99 (without F-prefix) is panic exit hardware that supports mechanical dogging on non-fire-rated doors.

Surface Vertical Rod (9827, 9927)

SVR devices add top and bottom engagement rods running on the door face, providing three-point locking for double door openings without a center mullion. The 9827 is the 98 series SVR and the 9927 is the 99 series SVR. Both use a dedicated center case (part 109358) which is different from the rim device center case (part 109012). These are not interchangeable. Confirm configuration before ordering any center case.

Concealed Vertical Rod (9847, 9947)

CVR devices route the rod hardware inside the door for architectural applications where surface rods are not acceptable. Hotel lobbies, healthcare reception areas, high-end commercial interiors. CVR parts must match the exact model and door prep. CVR installation is typically done at the factory; field replacement of internal rod components requires door removal in most cases.

Wide Door Cable (WDC)

The WDC configuration uses a cable rather than rigid rods for very wide double doors where rod flex would be a problem. Available on the 98/99 series for oversized openings.

Mortise Device (98/9975, XP98/XP99)

The mortise configuration integrates the 7500 mortise lock body into the panic device chassis for maximum security depth alongside code-compliant egress. The 7500 mortise lock body has been in service since approximately 1977. Browse mortise lock replacement parts for the 7500 body components that pair with the 98/9975 mortise exit device.

Panic vs Fire Exit Hardware on the 98/99 Series

Every 98/99 series device is available in both standard panic and fire exit hardware versions. Getting this wrong before ordering replacement parts is the most common mistake in 98/99 series maintenance.

Standard panic devices (98, 99, 9827, 9927): UL listed for panic exit applications. Support mechanical hex dogging. Channel cover plates specific to panic configuration.

Fire exit hardware (F-98, F-99, F-9827, F-9927): UL listed for fire exit hardware. The F-prefix in the model number confirms this. Must positively latch on every door close. Hex dogging is not permitted. Channel cover plates carry different part numbers from the panic versions.

Dogging on the 98/99 Series

Hex dogging holds the push pad depressed during business hours so the door operates as a push/pull entry without latching. Standard on all panic-rated 98/99 devices. Not available on F-series fire exit hardware.

Why Dogging Fails on the 98/99

The dogging shaft hole (part 090040) is approximately 1/4 inch deep. The most common cause of dogging failure in the field is using a short 5/32-inch hex key that does not reach full depth. Short keys round out the hex engagement point over repeated use, requiring shaft replacement. Always use the long version of the 5/32-inch hex key and seat it fully before rotating.

The dogging assembly has three components:

090040 Dogging Shaft: The piece the hex key engages. Field note: the pre-1998 shaft has a different profile. For devices manufactured before 1998, use part 050709 conversion kit.

090042 Dogging Adapter Spring: Locks the adapter into the mounting bracket.

090043 Dogging Adapter: The housing the shaft and spring fit through.

Parts That Fail First on the 98/99 Series

Based on actual field replacement frequency, here is a realistic sequence of what wears out first:

1. Dogging assembly: The most common maintenance item on high-traffic doors. Shaft strips, springs fatigue, adapters crack. All three components are available individually.

2. End cap and bracket: The plastic end cap on the hinge side of the device breaks under repeated contact. When it breaks, the dogging cover plate slides off. Von Duprin introduced the 900397 metal end cap kit in 2016 to replace the historically fragile plastic version. This is a worthwhile proactive upgrade on any high-use 98/99 device.

3. Push bar retrofit kit: The push bar assembly bends or deforms on high-abuse applications. Push bar retrofit kits are available for 3-foot and 4-foot door widths, replacing just the push bar without requiring a full device swap.

4. Center case: The center case (109012 for rim, 109358 for SVR) wears after decades of continuous use. The 109012 rim center case has been in production for approximately 40 years and replaces all non-fire-rated 98/99 rim center cases with backward compatibility to devices installed in the 1980s. This long backward compatibility chain is one of the most valuable maintenance advantages of the 98/99 series.

5. Latch return spring (090039): Used in the push bar assembly to return the latch. Fails from spring fatigue on very high-cycle doors.

Electrified Options on the 98/99 Series

The 98/99 series has the deepest electrified options catalog of any Von Duprin device. Each option converts or adds to the mechanical device without replacing the body.

QEL: Quiet Electric Latch Retraction

The QEL is a modular field-installable kit that adds electric latch retraction to a mechanical 98/99 device. When an authorized credential is presented, the latch retracts silently. This is the most commonly specified electrified conversion on existing 98/99 devices in phased access control upgrades. The HD-QEL variant adds hex dogging capability to the electrified device.

MEL: Motorized Electric Latch Retraction

Motor-driven latch retraction for applications where solenoid noise is not acceptable. Quieter operation than standard EL. Used in library environments, healthcare patient areas, and quiet office zones.

Chexit: Delayed Egress

Holds the door latched for 15 seconds after the push bar is activated, with a local alarm sounding during the delay. NFPA 101 compliant for controlled egress applications. Used in retail, psychiatric facilities, and any location where unauthorized egress must be deterred without blocking emergency egress.

RX: Request to Exit

A switch placed in the push bar that signals the access control panel when the bar is pressed. Notifies the system of an authorized egress event to prevent false alarms on the secured entry side. Standard on any 98/99 device integrated into an access control system where the door also serves as a secured entry. The electric strikes parts catalog covers the Von Duprin electric strikes on the frame side that work alongside RX-equipped exit devices.

LX: Latch Bolt Monitoring

Monitors the position of the latch bolt, signaling the access panel when the door is not properly latched. Used on fire doors and secured doors where latch compliance monitoring is required by the inspection program.

ALK: Alarm Exit Kit

Converts the 98/99 to an alarmed exit device. Powered by a 9-volt battery. Controlled by a mortise cylinder (not included). When the push bar is pressed, the 85-decibel alarm sounds. The ALK is shared across the 22, 33A, 35A, 98, and 99 series.

CON: Allegion Connect

Wireless integration into the Allegion Connect ecosystem for remote monitoring and control.

How to Order 98/99 Series Parts Without a Wrong-Part Return

Three pieces of information are required before placing any 98/99 series parts order.

1. Confirm the configuration: Rim or SVR changes the center case part number entirely (109012 vs 109358). CVR and mortise use model-specific parts. Confirm which configuration is on the door before opening any catalog page.

2. Check the manufacture date: The manufacture date is stamped near the mechanism housing on the device body. Devices manufactured before 1998 use old-style dogging assemblies. The conversion kit (part 050709) updates pre-1998 devices to current spec dogging components. Post-1998 devices use parts 090040, 090042, and 090043.

3. Confirm panic or fire exit hardware: The F-prefix in the model number confirms fire exit hardware. Channel cover plates, dogging kits, and some trim components carry different part numbers between panic and fire configurations. Never order channel cover plates without confirming first.

SecurityParts.com organizes the complete Von Duprin 98/99 series parts catalog by model with interactive exploded diagrams on every model page. You confirm the component visually before ordering. Pre-order compatibility support is available at 845-935-0301 or through the contact page.

Related Parts at SecurityParts.com

The 98/99 series operates as part of a complete door assembly. A full service call on an institutional door typically covers the exit device, the door closer, and sometimes an electric strike or lock hardware on the same opening.

For LCN door closer parts on the same opening, browse the door closers catalog by series. For Von Duprin electric strike parts, including 5100, 6100, 6200, and 6300 series, used on the frame side alongside 98/99 exit devices, browse the electric strikes catalog. For Von Duprin Guard-X exit alarm parts on secondary exits in the same building, browse the exit alarms catalog. For Schlage deadbolt parts on interior office doors in the same facility, browse the deadbolts catalog.

Browse all Von Duprin series: 22, 33A, 75, 88, 94/95, and the Guard-X, in the Von Duprin parts catalog, or explore the full commercial exit devices parts catalog to navigate by brand and series.

Frequently Asked Questions

If you're buying door hardware for a commercial project, you'll run into this choice pretty quickly: mortise lock or cylindrical lock? They both secure a door. They both come in Grade 1. But they work differently, install differently, and belong on different types of openings.

Security Parts carries parts for all three Falcon exit device series. The 19 Series is narrow stile, light-to-medium duty, rim and SVR only. The 24 Series is narrow stile, heavy duty, for aluminum storefront doors with stiles as narrow as 1-3/4 inches. The 25 Series is wide stile, heavy duty, for standard hollow metal and wood commercial doors. The 24 and 25 Series share a push pad design and the same service manual (108004). The most frequently replaced parts are the channel, end cap kit, dogging cover plate, and on electrified versions, the EL solenoid or HWEA alarm board. For pre-June 2012 alarm assemblies, the HWEA replacement board is part 650335.

Falcon exit devices are on more commercial egress doors in North America than any other panic hardware brand outside Von Duprin. The 19, 24, and 25 Series cover the full range of commercial applications: from light office and retail doors through aluminum storefront entries to institutional hollow metal fire-rated assemblies. Each series has distinct construction, stile requirements, and electrified option sets. Getting the right replacement part requires knowing which series is installed and which sub-configuration applies.

Browse the complete Falcon exit device parts catalog at SecurityParts.com, which includes the 19, 24, and 25 Series alongside the full Von Duprin and Detex exit device range. The Falcon hardware catalog covers all Falcon product lines including exit devices, mortise locks, and cylindrical locks.

Falcon 19 vs 24 vs 25 Series: Which One Is Installed

Before ordering any replacement part, identifying the series is mandatory. The three series look similar from a distance but are built for completely different door constructions. Ordering a 25 Series end cap for a 24 Series device, for example, produces a part that will not fit.

What Exit Device Configurations Mean for Parts Ordering

Each series offers multiple configurations that determine which latch hardware, rods, and strikes are involved. The configuration suffix on the model number tells you what is installed.

Why the Rim vs Vertical Rod Distinction Matters for Parts

A rim device has one latch point at the device head and uses a single rim strike on the door frame. A surface vertical rod device adds a bottom rod running from the device head to a floor bolt, creating two-point latching. The bottom rod, floor strike, and bottom latch components are additional parts unique to vertical rod configurations that rim devices do not use. If you are ordering a strike or latch bolt replacement, you need to know whether the installation is rim or VR before ordering.

The 25-V surface vertical rod uses a 3788 surface-applied top strike and a 2130 mortised bottom floor strike as the standard configuration. The 25-C concealed VR uses a 4188 mortised top strike and 2130 bottom standard, with 4155 and 2126A as bottom options. Fire-rated 25-C uses strike 1279 standard and F1280 for B label applications.

Falcon 19 Series Parts: Channels, End Caps and Key Components

The 19 Series uses a narrower channel profile than the 24 and 25 Series. All mounting screws are concealed; latch fasteners are exposed to the egress side. The push bar height is 1-3/4 inches. The stainless steel latch bolt has a 3/4-inch throw with deadlocking standard.

Falcon 24 Series Parts: Heavy Duty Narrow Stile

The 24 Series is built from extruded aluminum for maximum strength on narrow stile aluminum storefront doors. The construction provides greater impact resistance than the 19 Series at the same stile width. The push pad design is shared with the 25 Series, which is why both reference the same service manual 108004.

The 24 Series Door Thickness and End Cap Selection

The 24 Series serves aluminum storefront doors that come in two standard thicknesses: 1-3/4 inches (the most common commercial aluminum frame door) and 2-1/2 inches (thicker commercial storefront systems). The end cap kit part number changes based on this dimension. Part 650294 is for the 1-3/4-inch door and part 650348 is for the 2-1/2-inch door. Ordering the wrong kit produces an end cap that either leaves a gap at the stile edge or cannot seat against the door face at the correct depth.

Falcon 25 Series Parts: Wide Stile Heavy Duty

The 25 Series is Falcon's flagship exit device for standard commercial hollow metal and wood door applications. The center case is heavy wrought with sintered metal parts throughout the mechanism, making it more durable than extruded-only construction under heavy cycle loads. The top latchbolt is stainless steel with a 3/4-inch throw and deadlocking standard. Vertical rod configurations add a bottom bolt with a 1/2-inch throw.

25 Series Dogging: Half-Turn Hex, No Threads

Half-turn hex dogging is standard on the 25 Series with no threaded dogging components anywhere in the mechanism. Traditional threaded dogging on older exit devices requires turning a threaded rod several rotations, and the threads strip or corrode over time on high-cycle doors. The Falcon 25 Series half-turn hex design eliminates all threaded components from the dogging path. One half turn clockwise dogs the device. One half turn counterclockwise releases it. No stripping. No galling. This is why the 25 Series dogging mechanism outlasts competitor devices significantly on doors dogged and released multiple times daily.

Cylinder dogging is available as an option on the 25 Series using a 1-1/8-inch mortise cylinder with standard cam. This allows the outside cylinder to dog and release the device without carrying the hex key, which is the preferred configuration for reception desks and service counters where maintenance staff routinely dog the door at opening time.

25 Series Configurations and Stile Requirements

Stile requirements vary by 25 Series configuration. Standard 25-R and 25-V configurations require a 4-1/2-inch minimum stile. The 25-C concealed vertical rod configuration requires a 3-1/2-inch minimum stile on panic versions and 4-1/2-inch minimum on fire-rated F-25-C installations. The 25-CWDC (wood door wide cable configuration) requires a 6-1/2-inch minimum stile on wood doors. Ordering a 25-V or 25-C for a door with an undersized stile produces a device that cannot be correctly mounted.

25 Series Fire Ratings: A Label vs B Label

The Falcon 25 Series supports two UL fire ratings depending on the configuration. The B label (1-1/2 hour) is available on all 25 Series configurations. The A label (3-hour) is available on fire pairs (F-25-M x F-25-V or F-25-C), permitting up to 4-foot by 10-foot single doors and 8-foot by 10-foot pairs. When ordering strike replacements for fire-rated 25 Series installations, the fire strike specification matters. The F-25-C uses strike 1279 as standard and F1280 for B label applications. The F-25-V uses strike 299F for fire-rated top and 499F for fire-rated pairs with mullion.

Hex Dogging: How It Works and What Fails

Dogging is the function that holds the push bar depressed and the latch retracted, allowing the door to operate as a free-swinging door without requiring the push bar to be pressed on every pass. It is standard on the 24 and 25 Series panic versions and on the 19 Series panic version. It is never available on any fire-rated version of any series because holding a fire door latch retracted violates life safety code.

Hex dogging uses a hex key (Allen wrench) inserted into the dogging hole in the channel. On the Falcon 24 and 25 Series, the half-turn mechanism requires only a 180-degree rotation. The dogging cover plate conceals the dogging hole when not in use. This cover plate is a separately replaceable component if it is damaged or missing.

Electrified Options on the Falcon 24 and 25 Series

The Falcon 24 and 25 Series support a full range of electrified options for access control integration. Understanding the compatibility rules between these options prevents ordering combinations that cannot be installed together.

EL: Electric Latch Retraction

The EL option retracts the latch electrically without depressing the push bar, allowing the door to be opened from the outside by a credential reader, keypad, or building automation system. The EL solenoid operates at 24V DC and 0.34 amperes continuous duty. For 3-foot devices, the EL kit is part 650147. For 4-foot devices, it is part 650148. EL can be combined with FSA/FSE (fail safe/fail secure outside trim), DM (device monitoring), LM (latch monitoring), and AE/LK options. EL cannot be combined with ED (electric dogging), EA (exit alarm), HWEA (hard-wired exit alarm), or KOR (key override) on the same device.

Electric latch retraction serves two common use cases in commercial buildings. The first is controlled entry: a credential reader on the exterior side triggers the EL solenoid to retract the latch, allowing entry without pushing the panic bar. The second is electronic dogging during business hours: the building automation system energizes the EL solenoid for extended periods to hold the latch retracted as an alternative to mechanical hex dogging. This allows the door to operate in free-swing mode during hours and automatically re-latch when the solenoid is de-energized after hours.

EA and HWEA: Exit Alarm Options

The EA (exit alarm) option adds an audible alarm triggered when the push bar is pressed, providing delay notification or unauthorized egress alerting. The HWEA (hard-wired exit alarm) version connects to a building's wired fire alarm or security system.

The alarm circuit board replacement for pre-June 2012 HWEA assemblies is part 650335. This date boundary is critical: the alarm assembly design changed in June 2012. The 650335 board works only on pre-June 2012 assemblies. Post-June 2012 assemblies use a different alarm kit. Confirming the manufacturing date before ordering any alarm board replacement prevents a non-functional alarm installation.

KOR, LM, DM, RX: Monitoring and Override Options

KOR (key override) provides a cylinder that overrides the electrified outside trim functions without requiring electronic credentials. It is used when power failures need a mechanical fallback for authorized entry. LM (latch monitoring switch) monitors the latch bolt position and reports door open/closed status to the access control system. DM (device monitoring switch) monitors whether the push bar has been pressed. These two cannot be used on the same device because their switch mechanisms conflict. RX (request to exit switch) connects to an egress-side reader or motion sensor to signal the access control system that someone is approaching from the inside before the door opens.

How to Identify the Correct Part Before Ordering

Three pieces of information are needed before any Falcon exit device parts order.

1. Series (19, 24, or 25): Determined by the door construction and stile width as described above. The series number is typically visible on a label on the device channel or center case.

2. Configuration (R, V, C, CWDC, M): Visible from the door face. A rim device has a single latch point and no visible rod hardware on the door. A surface VR device has a visible bottom rod running down the door face to a floor strike. A concealed VR device has no visible rod hardware but two latch points (the concealed rods are inside the door stile).

3. Panic or fire-rated (prefix F-): Look for a fire label on the door or door frame. If a fire label is present, the device should be a fire-rated version. If ordering a replacement device, always match the fire rating of the original. If ordering a dogging cover plate, panic devices have a dogging hole; fire-rated devices do not.

Browse the exit device parts catalog at SecurityParts.com for all Falcon 19, 24, and 25 Series components with interactive diagrams. The Falcon hardware catalog covers exit devices alongside Falcon MA Series mortise locks and T Series cylindrical locks. Pre-order support is available at 845-935-0301 or through the contact page.

Falcon vs Von Duprin: Choosing Between the Two Exit Device Brands

Both Falcon and Von Duprin are Allegion brands. They share company ownership but serve different market positions and use different part ecosystems. Parts are not interchangeable between the two brands.

Von Duprin is the older and more widely installed brand in institutional, healthcare, and high-security government applications. The Von Duprin 98/99 Series is the dominant exit device in North American institutional buildings constructed before 2000. Von Duprin has a larger installed base and a wider parts aftermarket. Browse the complete Von Duprin parts catalog for 98/99, 22, 33/35A, 55, 75, 78, 88, and 94/95 Series devices.

Falcon is more common in mid-market commercial, retail, multi-family, and newer construction where the architectural aesthetic of the flush push pad and concealed fasteners is valued alongside ANSI Grade 1 performance at a competitive price. The 24 and 25 Series were specifically designed for the streamlined appearance requirements of modern commercial construction.

On any given building, both brands may be present: Von Duprin on older egress stairwell doors that have not been replaced, Falcon on newer tenant improvement entries and interior egress paths. SecurityParts.com stocks both, so a single order can service the complete building hardware schedule.

Related Parts and Products at Security Parts

A complete commercial egress door hardware package includes the exit device, door closer, and often an electric strike or exit alarm. SecurityParts.com stocks all of these for the same opening in one order.

For Von Duprin exit device parts on egress doors in the same building where Von Duprin is installed alongside Falcon hardware, browse the Von Duprin catalog. For Von Duprin electric strike parts on the door frame of any exit device installation with controlled entry, browse the electric strikes catalog. The Von Duprin 6300 electric strike is compatible with Falcon 24 and 25 Series rim devices. For commercial exit alarm parts including Von Duprin Guard-X and Detex ECL and EAX series, browse the exit alarms catalog. For LCN door closer parts on any fire-rated or controlled-closing egress door in the same building, browse the door closers catalog. For Schlage L Series and Falcon MA Series mortise lock parts on secured interior doors in the same facility, browse the mortise locks catalog.

Browse the complete all products and parts catalog to source Falcon, Von Duprin, Schlage, LCN, and Detex hardware in a single session.

Commercial mortise locks are heavy-duty locks installed inside a rectangular pocket cut into the edge of the door, with a self-contained lock body that houses the latchbolt, deadbolt, lever hub, cylinder, and internal linkages in one reinforced steel case. They're the standard for commercial buildings, hospitality, healthcare, institutional, and high-traffic facilities because they outperform cylindrical locks on durability, function variety, and security. This guide covers what mortise locks are, the ANSI function codes that define them, the major commercial brands you'll encounter, how to specify the right one, and how to source replacements without misordering.

What Is a Mortise Lock

A mortise lock is a heavy-duty lock assembly installed in a rectangular pocket (the "mortise") machined into the edge of the door itself. Unlike a cylindrical lock that passes a cylinder through two round holes bored through the door face, the mortise lock body is a self-contained mechanical assembly measuring approximately 6 inches by 4 inches by 1 inch. The case houses the latchbolt, separate deadbolt, lever hub, cylinder housing, and all internal linkages in one reinforced steel unit.

Everything load-bearing sits inside the door, not bolted to the surface. That single design choice is what makes mortise locks the dominant commercial lock category for openings that need to last twenty-plus years under heavy cycle counts.

How Mortise Locks Differ from Cylindrical Locks

The structural difference between mortise and cylindrical locks drives every other difference in performance, function, and price.

A cylindrical lock (sometimes called a bored lock) uses two cross-bored holes. The chassis passes through one, the latch crosses through the other, and trim mounts on both faces of the door. Cylindrical locks are faster to install, cheaper to manufacture, and work well on lighter-duty interior openings.

A mortise lock requires a precise pocket cut into the door edge, plus through-bores for the cylinder and lever hubs. The pocket prep takes more skilled labor at installation. In exchange, the mortise lock delivers a one-piece reinforced case, a separate 1-inch deadbolt that operates independently of the latch, and a chassis large enough to hold complex function-change mechanisms inside.

Three things mortise locks do that cylindrical locks generally can't: combine a latch and a separate deadbolt in one chassis, support classroom-security and institutional functions, and survive Grade 1 ANSI/BHMA testing on 2 million cycles.

ANSI Function Codes for Mortise Locks

The American National Standards Institute, working with the Builders Hardware Manufacturers Association, defines mortise lock behavior using F-codes. Every commercial mortise lock spec sheet references these codes. Knowing them is how you cross-reference one brand against another.

F01 Passage. Both levers always operate the latchbolt. No locking. Used on closet doors, conference rooms, interior pass-through openings.

F02 Privacy. Trim from either side retracts the latchbolt. Thumbturn inside retracts and projects a deadbolt. Emergency release from outside retracts the deadbolt. Used on bathrooms and bedrooms.

F04 Classroom. Outside lever locked or unlocked by key from outside. Inside lever always free for egress. Used on classrooms where teachers control access from the corridor.

F05 Office. Outside lever locked by toggle button inside or by key from outside. Inside lever always free. Used on offices where the occupant locks the door from inside.

F07 / F08 Storeroom. Outside lever permanently fixed. Key from outside retracts latchbolt for entry. Inside lever always free for egress. Used on IT rooms, supply rooms, mechanical rooms, electrical closets.

F13 Classroom Security. Both levers can be locked from inside the classroom. Provides lockdown capability without requiring the teacher to step into the corridor. Used in K-12 active-shooter response specifications.

F14 Classroom Security with Deadbolt. Adds a separate deadbolt to the F13 function for additional lockdown security.

F17 Deadbolt. Standalone deadbolt function without latch. Used on storage and tenant security applications.

F20 Entrance. Latch retracted by key outside or inside lever. Outside lever locked or unlocked by key. Used on suite entries and tenant doors.

F21 Apartment Corridor. Combines latch operation with deadbolt control specifically for multifamily corridor doors.

F31 Exit. Outside lever rigid at all times. Inside lever retracts the latchbolt. Used on emergency exit doors that don't allow re-entry from outside.

Top Commercial Mortise Lock Brands and Their Series

Five brands account for the vast majority of commercial mortise locks specified in North America. The function codes are standardized across all of them, which means model numbers cross-reference predictably once you know the function.

Schlage L Series (L9000). Allegion's flagship commercial mortise line. Over 40 functions, 31 lever designs, 14 finishes. UL listed for 3-hour fire door assemblies. The most widely specified mortise lock in North American commercial construction. The Schlage L Series parts and diagrams guide covers the component breakdown. Electrified variants include the L9580 motorized latch retraction storeroom lock for access-controlled openings.

Sargent 8200 Series. ASSA ABLOY's primary commercial mortise lock. Grade 1, full function range, broad finish and lever selection. Common on East Coast institutional specifications.

Corbin Russwin ML2000 Series. Another ASSA ABLOY brand. Functionally comparable to the Sargent 8200, often specified on legacy buildings where Corbin Russwin was the original brand.

Best 45H Series. Best Access Systems (dormakaba). Grade 1 mortise lock with field-removable core compatibility. Heavy presence in K-12 and higher-education specifications.

Yale / Accentra 8800 Series. Recently rebranded from Yale to Accentra under ASSA ABLOY. Full Grade 1 commercial mortise line.

Falcon MA Series. Allegion's mid-tier commercial mortise brand. Grade 1 performance at a different price point than Schlage L Series. Common on multifamily and budget-conscious commercial specifications.

Von Duprin 7500 Series. The mortise lock that pairs with Von Duprin 88 Series mortise exit devices. Field-reversible, field-selectable functions, electrified E7500 variant available. The Von Duprin 7500 parts manual covers the full breakdown.

Adams Rite 4500 / 4900 Series. Specialized narrow-stile mortise locks for aluminum entrance doors. Used on storefront and curtain wall applications where standard mortise hardware won't fit the door section.

Cal-Royal NM Series. Grade 1 commercial mortise at a budget tier. Used on cost-sensitive commercial and apartment corridor specifications.

Components Inside a Commercial Mortise Lock

The internal architecture is consistent across brands, even when model numbers differ. Knowing the component breakdown is what determines whether you order a complete lock or a single replacement part.

Lock case. The reinforced steel housing that contains all internal mechanisms. Field-replaceable as a complete unit on most failures.

Latchbolt. The main spring-loaded bolt that engages the strike when the door closes. Stainless steel on most production runs. Anti-friction tongue on Grade 1 units.

Deadbolt. Separate 1-inch throw bolt operated independently of the latch. Engages on key turn or thumbturn. The presence of a separate deadbolt is one of the defining features of mortise locks vs cylindrical locks.

Auxiliary latch (deadlocking). Smaller secondary latch that deadlocks the main latchbolt when the door is closed. Prevents shimming. Standard on Grade 1 commercial mortise locks.

Lever hub and spindle. The internal mechanism that translates lever rotation into latch retraction. Worn spindles cause lever droop and loose feel.

Cylinder housing. Threaded opening that accepts the keyway cylinder. Most commercial mortise locks accept Schlage-prep mortise cylinders, which means standard Everest 29, Primus, FSIC, and SFIC cylinders cross between brands.

Faceplate. The visible plate at the edge of the door covering the lock pocket. Often field-adjustable for door bevel angle.

Strike. The plate or pocket in the door frame that receives the latchbolt and deadbolt when the door closes. Specified separately from the lock body.

Trim (escutcheons and roses). The decorative and structural cover on both faces of the door. Available in various designs depending on brand.

Where Commercial Mortise Locks Are Used

Mortise locks dominate four building categories.

Healthcare facilities. Hospitals, clinics, and behavioral health buildings. Quiet operation, ligature-resistant trim options on the L Series and Sargent equivalents, and the durability to handle 24/7 cycle counts are why mortise hardware is specified here over cylindrical.

K-12 and higher education. Classrooms, administration, mechanical rooms, and lockdown-capable corridor doors. F13 Classroom Security and F14 Classroom Security with Deadbolt functions are the reason most K-12 spec sheets list mortise hardware after the Sandy Hook era specifications became standard.

Commercial office buildings. Tenant entries, suite doors, executive offices, and high-security access points. Mortise hardware is the standard on Class A office construction.

Hospitality. Hotels, conference centers, and high-end retail. The aesthetic continuity of mortise hardware (no visible faceplate from outside, clean lever and escutcheon styles) drives the spec choice.

Mortise locks are also common on government buildings, courthouses, military facilities, multifamily corridor doors, and any building where the durability premium pays back over a 20-plus year service life.

Grade 1 vs Grade 2 vs Grade 3 Mortise Locks

ANSI/BHMA A156.13 defines three grades for mortise locks based on standardized testing.

Grade 1. The highest commercial standard. Cycle test: 1 million minimum (most current Grade 1 mortise locks rate 2 million cycles). Resistance test: 1,000 inch-pounds. Door impact test passed. Used on commercial, institutional, and high-traffic openings.

Grade 2. Light commercial standard. Lower cycle and resistance requirements. Used on light commercial and high-end residential openings.

Grade 3. Residential standard. Not typically specified on commercial construction.

For commercial buildings, Grade 1 is the baseline. Grade 2 mortise locks exist but show up rarely in commercial spec because the cost gap to Grade 1 is small enough that most spec writers default to the higher grade.

How to Specify the Right Commercial Mortise Lock

Five specifications lock in every commercial mortise lock order.

Function. ANSI F-code that defines the lock behavior. Passage, privacy, classroom, office, storeroom, deadbolt, entrance, or one of the security-specific variants.

Brand and series. Schlage L9000, Sargent 8200, Best 45H, Corbin Russwin ML2000, Yale/Accentra 8800, Falcon MA, or others depending on existing building specification.

Lever or knob style. Trim selection. Lever required for ADA compliance on accessible openings. Knob still permitted on certain non-accessible commercial doors.

Finish. ANSI/BHMA finish code. 605 (bright brass), 612 (satin bronze), 619 (satin nickel), 622 (matte black), 625 (bright chrome), 626 (satin chrome), 629 (bright stainless), 630 (satin stainless), 643e (aged bronze) are the most common.

Cylinder option. P (full-face Schlage 6-pin), L (less cylinder), B (SFIC less core), R (FSIC), or one of the brand-specific cylinder variants. Cylinder choice determines key system compatibility.

Door thickness and handing are usually field-adjustable on Grade 1 mortise locks, but verify with the spec sheet. Some institutional locks require handing at order.

How to Replace a Commercial Mortise Lock

Three approaches depending on what failed.

Complete lock body replacement. When the chassis itself fails (internal mechanism worn, multiple components failed). Order the matching SKU including function, finish, and trim. Reuse the existing strike if it's in good condition.

Component-level replacement. When a single part failed (worn latchbolt, broken auxiliary latch, lever droop from spindle wear). Order the specific part. Most Grade 1 mortise lock manufacturers stock individual components.

Full re-spec to current product. When the existing lock is on a legacy series that's no longer manufactured. Schlage L9000 has been continuously produced, so retrofit is straightforward. Older Yale, Corbin, and Russwin lines may require cross-referencing to the current Accentra or Corbin Russwin equivalent.

Before ordering replacement, pull the model number off the lock face. Most commercial mortise locks stamp the brand and series directly on the faceplate or the lock body.

Why Choose Security Parts for Commercial Mortise Locks

Security Parts has been the go-to source for commercial door hardware components in the United States since 2001. That's more than two decades of stocking, shipping, and verifying parts for the exact hardware that shows up on commercial buildings. Mortise locks are a category where that experience matters more than catalog breadth, because the wrong function code on a service order costs a return cycle and a building day with the door out of service.

What sets the team apart is the depth on Allegion brands. As a long-standing distributor for Schlage, Von Duprin, LCN, and Falcon hardware, Security Parts stocks the Schlage L Series, Von Duprin 7500, and Falcon MA mortise lock components on the shelf, not on a three-week drop ship. Lock bodies, latchbolts, auxiliary latches, trim spindles, cylinder housings, and complete mortise lock assemblies ship the same day on stocked SKUs.

Spec verification is the part most distributors don't do. If you're not sure whether the existing lock is a Schlage L9050 office or an L9070 classroom, whether the cylinder option crosses between brands, or which function code matches the application, the team will work through it with you on the phone before the order ships. That's how the wrong-function return cycle gets prevented, and it's the single biggest cost-saver on commercial service calls where a misordered lock means another day of manual access on a building that doesn't have that runway.

For facility managers, locksmiths, access control integrators, contractors, and spec writers sourcing commercial mortise lock hardware across institutional portfolios, Security Parts combines stocked depth, brand specialization, and the technical bench to verify configurations. That combination is what builds the long-term sourcing relationships the team has held with K-12 districts, healthcare networks, and government facilities for over twenty years.

Closing

Commercial mortise locks are the standard hardware on every building category where security, durability, and function flexibility matter. The brand and series may vary, but the underlying ANSI function codes are universal, and the component architecture is consistent across the Big Five (Schlage L Series, Sargent 8200, Best 45H, Corbin Russwin ML2000, Yale/Accentra 8800).

When specifying or replacing a commercial mortise lock, confirm the function code first, brand and series second, then trim and finish. Source from a distributor that stocks the specific brand line your building runs on. Security Parts has carried commercial mortise lock hardware since 2001, with verified configurations and spec guidance by phone at 845-935-0301.

Frequently Asked Questions

What is the difference between a mortise lock and a cylindrical lock?

 A mortise lock installs in a pocket cut into the door edge with a self-contained reinforced steel case. A cylindrical lock passes through two cross-bored holes in the door face. Mortise locks are stronger, support more functions, and last longer under commercial cycle counts.

What does ANSI/BHMA Grade 1 mean for a mortise lock?

 Grade 1 is the highest commercial standard under ANSI/BHMA A156.13. It requires the lock to pass cycle testing (typically 2 million cycles), resistance testing, door impact testing, and warped door testing. Grade 1 is the baseline specification for commercial buildings.

Which is the most common commercial mortise lock brand?

 Schlage L Series (L9000) is the most widely specified commercial mortise lock in North America. Sargent 8200, Best 45H, Corbin Russwin ML2000, and Yale/Accentra 8800 are the other major commercial brands.

Can mortise lock functions be changed in the field? 

Yes, on most brands. Schlage L Series, Sargent 8200, and Von Duprin 7500 all support field-selectable functions on the same chassis through internal mechanism adjustments. The specific procedure varies by brand and series.

Are mortise locks fire rated?

 Most Grade 1 commercial mortise locks carry UL fire ratings up to 3 hours when installed on listed fire door assemblies. Verify the specific lock's UL listing against the door's fire rating requirement.

What's the difference between a mortise lock and a mortise deadbolt? 

A mortise lock combines a latchbolt and (on most functions) a separate deadbolt in one chassis. A mortise deadbolt is a leverless lock with only the deadbolt, used on auxiliary security applications. Schlage L9460 is the standard mortise deadbolt under the L Series chassis.

How long do commercial mortise locks last? 

Grade 1 commercial mortise locks rated for 2 million cycles typically last 15 to 25 years in commercial service depending on traffic. Heavy-cycle openings (corridor doors, classroom entries) may need component-level service after 10 to 15 years.

Commercial door operators are the powered mechanisms that open and close a door automatically when triggered by a push button, motion sensor, or access control signal. They're not door closers. A door closer holds the door shut after manual opening. A door operator actively opens the door under power, then closes it under controlled return. The two get confused constantly on hardware schedules, and that confusion causes the wrong parts to get ordered.

This guide covers what door operators actually do, the LCN and Norton models most commonly installed on commercial buildings, how to identify the unit in front of you, and where to source replacement parts when one fails. If you're working on a manual door closer instead, see the LCN door closer parts guide for that line.

What Commercial Door Operators Do

A commercial door operator is a motorized device mounted on or in the door frame that swings the door open when energized. The operator carries an internal motor (usually electric, sometimes hydraulic on heavy-duty industrial models) and a control board that manages opening speed, hold-open time, and closing return. Most commercial door operators run on 120V AC for the unit itself, with low-voltage activation signals (12V or 24V) coming in from access control, push plates, or wave sensors.

The two functional categories you'll encounter most:

Low-energy door operators. These swing the door at a controlled speed governed by ANSI/BHMA A156.19. Low-energy means the door's opening force and speed stay under a threshold that doesn't require safety sensors or guard rails. Common on accessible restrooms, single-occupancy entries, and ADA-compliant office doors.

Full-energy automatic door operators. Higher opening force and faster swing. Governed by ANSI/BHMA A156.10. Requires presence sensors, safety beams, or guard rails because the door moves with enough force to injure if someone walks into it. Common on retail entrances, hospitals, and high-traffic commercial buildings.

Most door operators on commercial schedules in North America are low-energy units. They're cheaper, code-compliant for most applications, and don't require the sensor stack that full-energy operators do.

Major Commercial Door Operator Models

LCN 4640 Series (Senior Swing). The most-installed low-energy door operator on commercial schedules in North America. Surface-mounted, hydraulic-assist, electric drive. Standard on accessible restrooms, conference rooms, and ADA office doors. Specified across K-12, healthcare, and government buildings.

LCN 4642 Series. Heavy-duty version of the 4640 platform. Higher operating force, more durable internal components, longer service interval. Specified where the door sees high cycle counts or wind load.

LCN 4630/4631 Series. Mid-range models in the LCN low-energy line. Less common than the 4640/4642 but still in active service on installs from the last fifteen years.

Norton 5700 Series. Norton's primary low-energy door operator. Functionally comparable to the LCN 4640. Common on Norton-branded hardware schedules.

Norton 5800 ADAEZ Pro. A more recent Norton operator built specifically for ADA-compliant restroom and accessible-entry applications.

Stanley Magic Force / Magic Swing. Older Stanley low-energy operators still found on legacy installs. Stanley sold the line to dormakaba years ago, so service support has narrowed.

Horton 7000 Series. Heavy commercial swing door operator. Used on hospitals, retail entrances, transportation facilities.

For most replacement work on commercial buildings under twenty years old, the parts you'll need are LCN 4640/4642 or Norton 5700.

How to Identify Your Door Operator Before Ordering Parts

Five checks before placing a parts order. Each one prevents a return.

Read the model number off the unit. Most commercial door operators stamp the model number on the cover or inside the housing. LCN 4640, 4642, Norton 5700, Stanley Magic, all label themselves. The cover usually comes off with a single screw or quarter-turn fastener.

Identify the mounting style. Surface-applied (mounted to the face of the frame or door), concealed overhead (recessed into the header), or in-floor (mounted in the floor under the door pivot). Mounting style determines which parts cross between models.

Note the drive type. Electric (motor-driven), hydraulic-assist (motor plus hydraulic dampers), or pneumatic (older units, less common in modern commercial). Drive type determines what internal components are in the unit.

Confirm the voltage. Most commercial door operators run 120V AC for the main unit. Activation signals come in low-voltage (12V or 24V). Some legacy units run different voltage, so confirm at the unit before ordering electrical components.

Pull the cycle count if available. High-cycle doors (retail, hospital entrances) wear different parts than low-cycle doors (conference rooms, single-occupancy restrooms). Cycle count helps predict which component actually failed versus what looks worn cosmetically.

Common Door Operator Service Issues and What to Replace

Four failure patterns account for most door operator service calls.

Door doesn't open on signal. Usually a control board issue, a low-voltage wiring fault, or a failed motor. Test the activation signal at the operator's low-voltage input first. If signal is present and the motor doesn't run, the control board is the next suspect. If the board is good and the motor still doesn't actuate, replace the motor.

Door opens but doesn't close fully. Hydraulic damper issue or arm linkage wear. On LCN 4640 and 4642 units, the hydraulic damper assembly is the wear component. Replace as a single unit rather than rebuilding internals.

Door slams shut or closes too fast. Closing speed adjustment is out of range, or the closing valve has failed. Adjust the valve first. If the adjustment doesn't hold, replace the valve assembly.

Door operator binds, hesitates, or makes unusual noise. Internal mechanical wear, usually on the spindle or drive gear. On older units (10-plus years), full operator replacement is often more economical than rebuilding internals.

Door Operator Parts Categories

The component breakdown across LCN and Norton low-energy door operators follows a common architecture. The parts categories you'll source from:

Motor and drive assembly. The motor itself and the gear train that connects motor torque to the spindle.

Control board. Manages opening signal, hold-open time, closing speed, and obstruction sensing. Brand and model specific.

Hydraulic damper assembly. Handles controlled closing. Common wear part on hydraulic-assist units.

Arm and linkage. Connects the operator spindle to the door. Standard arm for push-side mount, parallel arm for pull-side, slide track for narrow header installations.

Activation devices. Push plates, wave sensors, motion detectors, push buttons. These are usually separate accessories, not internal operator components.

Cover and housing. Cosmetic and protective. Field-replaceable on most units.

Spindle and pinion. Internal mechanical components. Replaced as part of a major service or operator overhaul.

Power supply and transformer. Some units integrate the transformer in the housing. Others use an external transformer. Voltage-specific.

Door Operators vs Door Closers: Don't Confuse Them on Parts Orders

This is the single most common mistake on door operator parts orders. A door closer (LCN 4040XP, 4041, 4111, Norton 1601, Sargent 351) is a passive hydraulic device that closes a door after someone manually opens it. It doesn't open the door under power. Door closers don't have motors, control boards, or activation inputs.

A door operator opens the door under power. It carries a motor, a control board, and accepts activation signals.

If you're ordering "door closer parts" for what's actually a door operator, the parts won't fit. If you're ordering "door operator parts" for what's actually a heavy-duty door closer, same problem. Confirm the unit type before sourcing, especially on older buildings where the same opening may have housed both types over the years.

The door closer parts catalog handles manual closers. The automatic operator section handles powered units.

How to Source Door Operator Replacement Parts

For LCN 4640 and 4642 door operators, Security Parts stocks the LCN brand line including operator components, hydraulic dampers, arms, and control boards. Same-day shipping on stocked components.

For Norton 5700 and 5800 door operators, source from a Norton-authorized distributor or through Security Parts depending on stock. Norton control boards are model-specific and shouldn't be cross-substituted between series.

For Stanley Magic Force and Magic Swing legacy units, parts availability has narrowed since the dormakaba acquisition. On older Stanley units, replacement of the full operator with a current LCN or Norton model is often more economical than chasing legacy parts.

Before ordering any door operator part, confirm the unit's model number, mounting configuration, and voltage. For configurations not visible online, call 845-935-0301. Two minutes of spec verification prevents the wrong-part return cycle on a service call that probably doesn't have those days to spare.

Why Choose Security Parts for Door Operator Components and Replacement

Security Parts has been the go-to source for commercial door hardware components in the United States since 2001. That's more than two decades of stocking, shipping, and verifying parts for the exact hardware that fails on commercial buildings. Door operators are a category where that experience matters more than catalog breadth, because the wrong part costs a service call and a day of building downtime. The right one ships the same day and gets the door back in service before lunch.

What sets the team apart is the depth on Allegion brands. As a long-standing distributor for LCN, Von Duprin, Schlage, and Falcon hardware, Security Parts carries the LCN 4640, 4642, and broader Senior Swing door operator parts in stock, not on a three-week drop ship. Hydraulic damper assemblies, control boards, arm and linkage components, motors, covers, and replacement spindles all ship the same day on stocked SKUs.

Spec verification is the part most distributors don't do. If you're not sure whether the unit on the door is a 4640 or a 4642, whether the control board you need is original or a current replacement, or whether the operator can be retrofitted with a current ADA-compliant unit, the team will work through it with you on the phone before the order ships. That's how the wrong-part return cycle gets prevented, and it's the single biggest cost-saver on commercial service calls where a misordered part means another business day with a manual door.

For facility managers, locksmiths, access control integrators, and contractors sourcing door operator parts across an institutional portfolio, Security Parts combines stocked depth, brand specialization, and the technical bench to verify configurations. That combination is what builds the long-term sourcing relationships the team has held with K-12 districts, healthcare networks, and government facilities for over twenty years.

Closing

Commercial door operators are infrastructure. They cycle thousands of times a year on busy openings and stay in service for two decades when they're maintained. When one fails, the door becomes either a manual-only opening (frustrating for users) or a security gap (if the operator is part of an access-controlled entry). Either way, the fix needs to be fast and the parts need to be right.

Identify the unit model before ordering. Distinguish door operator from door closer. Confirm voltage and mounting configuration. Then source from a distributor that stocks the specific LCN or Norton line your building runs on. Security Parts has carried LCN commercial hardware since 2001, with verified configurations and spec guidance by phone at 845-935-0301.

Frequently Asked Questions

What's the difference between a door operator and a door closer?

 A door operator opens the door automatically under power and controls the close. A door closer is a passive device that only closes the door after manual opening. Door operators carry a motor, control board, and activation inputs. Door closers do not.

Which door operators are most common on commercial buildings?

 LCN 4640 (Senior Swing) and 4642 are the most-installed low-energy door operators in North America. Norton 5700 series is the next most common. Together these account for the majority of low-energy commercial door operator installs in the last two decades.

Are door operators required to meet ADA standards?

 On accessible openings, yes. Door operators on ADA-compliant entries must meet ANSI/BHMA A156.19 for low-energy units, which governs opening speed and force to ensure the door is safe and operable for users with mobility limitations.

Can a door operator be added to an existing manual door? 

Yes, on most commercial doors. Low-energy door operators like the LCN 4640 are surface-mounted and can retrofit an existing door without frame modification, provided the door has structural mounting points and access to 120V AC for the operator unit.

How long do commercial door operators last?

 Properly installed and maintained door operators typically last 15 to 20 years on low-cycle openings. High-cycle doors (retail entries, hospital corridors) may see 7 to 10 years before major service. Hydraulic dampers, control boards, and motors are the components that fail first.

What voltage does a commercial door operator require? 

Most commercial door operators run on 120V AC for the main unit, with low-voltage activation signals at 12V or 24V coming from push plates, sensors, or access control panels. Confirm voltage at the unit before ordering electrical components.

Where can I source door operator parts?

 Security Parts stocks commercial door operator components including LCN 4640 and 4642 parts, control boards, hydraulic dampers, and arm assemblies. Call 845-935-0301 for configurations not visible online.

The Schlage L9580 vs electric strike decision comes down to one question most spec sheets never frame clearly: do you modify the lock, or do you modify the frame? An electric strike releases the door by swinging open a keeper cut into the frame. The L9580 releases the door by retracting the latchbolt inside the lock itself. Both get you electronic access control. They get you there in very different ways, with different costs, security levels, and code implications.

This guide compares them on the factors that actually decide a spec. If you need the full breakdown of the lock itself, see our Schlage L9580 guide. This piece is about choosing between the two approaches.

The Core Difference in How They Work

An electric strike replaces the fixed strike plate in the door frame. When the access control panel sends a signal, the keeper pivots and lets the latchbolt swing free, so the door can be pulled or pushed open. The lock on the door never changes state. Its latch stays extended the whole time.

The Schlage L9580 works the opposite way. The lock body stays in the frame as a standard mortise lock, and a motor inside the chassis physically pulls the latchbolt back into the case on a 24V DC signal. The frame's strike never moves. The door becomes pushable because the latch is gone, not because the keeper released.

That single mechanical difference drives everything else in the comparison.

Frame Impact: The Biggest Practical Divider

Electric strikes require the frame to be cut and routed for the strike body and its wiring. On new construction with hollow metal frames prepped at the factory, that's simple. On a retrofit, it's invasive. Cutting an existing frame for a strike is labor, it can weaken the frame, and on fire-rated assemblies it often isn't permitted at all without a tested, listed fire-rated strike.

The L9580 retrofits the same mortise pocket that already holds a mechanical L9080 or any L9000 lock. The frame is never touched. Wiring runs through the door via an electric hinge or door loop. For any building where the frames are already prepped for mortise locks, this is the cleaner path by a wide margin.

If your project is a renovation with existing mortise-prepped doors, frame impact alone often settles the decision in favor of the L9580.

Security: Latch Retracted vs Keeper Released

With an electric strike, the lock's latchbolt stays fully extended. Only the frame keeper releases. That's secure enough for most interior openings, but the weak point is the frame cutout. A strike plate routed into a frame is structurally less robust than an intact frame holding a deadlocking latch.

The L9580 keeps a one-piece Grade 1 mortise body and a deadlocking auxiliary latch, which prevents shimming when the door is closed. On openings that face genuine forced-entry risk, perimeter doors, cash rooms, pharmacies, server rooms, the mortise lock approach is the tougher build.

For low-risk interior doors, the security gap is small enough that other factors decide. For high-security openings, the L9580 wins on physical security.

Noise: A Real Factor in Healthcare and Quiet Spaces

This one gets overlooked until it becomes a complaint. AC-powered electric strikes buzz when energized. DC strikes click. In a hospital corridor at 3 a.m., a library, a courthouse, or any space sensitive to repeated sound, that buzz or click on every access event is a problem.

The L9580 uses an ultra-quiet motor. Latch retraction is near silent. This is a major reason Allegion positions the motorized latch retraction line for healthcare and education, where doors cycle constantly and noise discipline matters. If the opening is in a quiet-sensitive environment, the L9580 has a clear edge.

Fire-Rated Openings: Code Narrows Your Options

On a fire-rated door assembly, an electric strike has to be a tested, listed fire-rated strike, and on a fire door it must fail secure (latched on power loss) so the door stays a barrier during a fire. Many standard electric strikes don't qualify, which limits your selection.

The L9580 is built on an L Series chassis UL listed for 3-hour fire door assemblies. Because it's latch-retraction-only, it defaults to its mechanical storeroom behavior when power is removed, the latch extends and the door secures, which aligns with fire-door requirements under NFPA 80. For fire-rated openings, the L9580 is often the simpler path to a compliant install.

Aesthetics: Visible Hardware vs Clean Lines

An electric strike adds a visible faceplate in the frame. In utility spaces, nobody cares. In a hotel lobby, a healthcare reception area, or a high-end commercial interior, that faceplate matters to the architect.

The L9580 looks identical to a standard mechanical mortise lock from the outside. No visible electronic component, no frame faceplate. If the design intent is to hide the access control layer, the mortise lock approach wins.

Cost Factors Without the Sticker Price

The hardware comparison isn't apples to apples, and the real cost lives in the install, not the part. Electric strikes generally carry a lower hardware cost, but frame cutting, fire-rated strike requirements, and wiring labor can close that gap fast on a retrofit. The L9580 carries a higher hardware cost but a lower install burden on mortise-prepped doors because the frame stays untouched.

The honest way to evaluate it: on new construction with factory-prepped frames, the electric strike often costs less installed. On retrofits with existing mortise doors, the L9580 frequently comes out even or ahead once frame labor and fire compliance are counted. Run the comparison per opening, not per catalog line.

When Each One Wins

The electric strike is the better call when the door uses cylindrical hardware you want to keep, when the budget is tight on simple interior openings, when the frame is already prepped for a strike, or when you only need to add access control to an existing lock without replacing it.

The L9580 is the better call on mortise-prepped retrofits where the frame can't be cut, on fire-rated openings, on quiet-sensitive environments like healthcare, on high-security doors, on auto operator and hands-free applications where the latch needs to fully clear, and anywhere the access control layer needs to stay visually invisible.

Frequently Asked Questions

Is the Schlage L9580 more secure than an electric strike?

 On high-risk openings, yes. The L9580 keeps a one-piece Grade 1 mortise body with a deadlocking auxiliary latch, while an electric strike relies on a keeper routed into the frame. For low-risk interior doors, the difference is minimal.

Can the L9580 replace an electric strike on a fire-rated door?

 Often, yes. The L Series chassis is UL listed for 3-hour fire assemblies and fails secure on power loss, which aligns with fire-door code. Electric strikes on fire doors must be specifically fire-rated and fail secure, which limits the options.

Why is the L9580 quieter than an electric strike? 

The L9580 retracts its latch with an ultra-quiet motor. AC electric strikes buzz and DC strikes click on each access event, which makes the L9580 preferable in healthcare, libraries, and other quiet-sensitive spaces.

Is an electric strike cheaper than the L9580? 

The hardware usually costs less, but frame cutting, wiring labor, and fire-rated strike requirements can erase that gap on retrofits. Evaluate installed cost per opening, not hardware cost alone.

Which one works better with auto operators? 

The L9580. It fully retracts the latch so the door clears cleanly for hands-free operation, which is why it's specified for accessible restrooms and infection-control corridors.

Closing

The Schlage L9580 vs electric strike choice isn't about which technology is better in the abstract. It's about which one fits the opening. Frame condition, fire rating, security level, and noise sensitivity decide it more than hardware cost does. For mortise-prepped retrofits, fire-rated doors, and quiet environments, the L9580 usually wins. For simple interior openings and frames already cut for a strike, the electric strike still earns its place.

Spec it per door. When you're ready to source either side, Security Parts stocks commercial mortise locks and electric strikes, and the team has verified configurations on commercial hardware since 2001. Reach them at 845-935-0301.

A Von Duprin exit device series comparison is not just a product selection exercise. It is a specification decision that determines code compliance, maintenance costs, electrified options availability, and parts compatibility for the life of the opening. Von Duprin has been manufacturing panic exit hardware since 1908, and today its active product lineup covers fourteen series. Each one was engineered for a specific set of conditions no other series addresses equally well. The cost of specifying the wrong series shows up at installation when the device physically does not fit, at the first NFPA 80 inspection when the fire rating fails, and every time a maintenance order ships the wrong part because the series was never correctly confirmed.

Four Questions That Narrow the Field Before You Look at a Catalog

Is the door fire-rated?

 If yes, the exit device must positively latch every time the door closes. Fire-rated Von Duprin configurations add "-F" to the model number and remove the hex dogging function. The device must also carry a UL fire door listing.

Single door or double door without a center post?

 Single doors and paired doors with a mullion use rim configurations. Double doors without a center post require surface vertical rod (SVR) or concealed vertical rod (CVR) configurations.

What is the stile width? 

Aluminum storefront and glass doors with stile widths as narrow as 1-3/4 inches require narrow-stile devices. Standard hollow metal commercial doors use wide-stile devices.

Is electrified access control required now or anticipated? 

The crossbar series (55 and 88) are mechanical-only by design. If electronic integration will ever be needed at the device level, a push pad or touchbar series with electrified options must be specified.

The Complete Series Comparison

22 Series: Mid-Range Grade 1

Applications: Employee entrances, parking garage stairwells, healthcare clinics, multi-family corridors, back-of-house retail.

Why: ANSI A156.3 Grade 1 performance at a lower specification cost than the 98/99. Not as deep an electrified options catalog, but covers the essentials: ALK alarm kit, QEL modular conversion, MEL motorized latch retraction, RX request to exit.

Parts note: Center case 109012 (rim) or 109358 (2227 SVR). Pre-1998 devices use old-style dogging assemblies; convert with part 050709. Dogging hole is only 1/4 inch deep, long 5/32-inch hex key is mandatory.

33A/35A Series: Narrow-Stile Touchbar

Applications: Aluminum storefronts, narrow-stile glass doors, applications where a full-width touchbar is specified over a push pad. Minimum stile width: 1-3/4 inches.

Why: The narrow-stile sibling of the 98/99 for aluminum frame and glass doors. The touchbar runs the full width of the door, engaging the release mechanism anywhere along its length. The 35A adds an integral door position switch.

Electrified: Second-deepest options catalog outside the 98/99. Chexit delayed egress, E7500 electrified mortise lock, pneumatic options, Allegion Connect, electric power transfers.

55 Series: Narrow-Stile Crossbar

Applications: Historic renovations, ornate institutional lobbies, applications requiring crossbar aesthetics on a narrow-stile door.

Why: Cast brass or bronze plated to finish specification. Integrates the 7500 mortise lock body. Specified where the architectural context demands a traditional crossbar appearance in a narrow-stile frame.

No electrified options at the device level.

75 Series: Standard Commercial Grade 1

Applications: Healthcare facilities, standard commercial offices, light institutional openings requiring Grade 1 performance without full institutional specification cost.

Why: Sits between the 22 and 98/99 in specification depth and cost. Rim, SVR, and CVR configurations. Electrified options: ALK, MEL, QEL modular conversion, Allegion Connect. The center case reinforcing bracket on the 75 Series adds structural support on high-use corridor openings.

78 Series: Narrow-Stile Push Pad

Applications: Aluminum storefront and glass doors where a push pad is specified over a touchbar. Minimum stile clearance: 1-3/4 inches.

Why: The push pad equivalent of the 33A/35A for narrow-stile applications. Rim, SVR, CVR, and WDC configurations. Electrified options: ALK, MEL, QEL modular conversion, Allegion Connect.

Critical parts note: 78 Series components are not interchangeable with any wide-stile Von Duprin series. Narrow-stile form factor throughout.

88 Series: Wide-Stile Crossbar, Abuse-Resistant

Applications: Correctional facilities, behavioral health units, secure government floors, any application where hardware faces deliberate sustained force.

Why: In continuous production since the 1950s. Ships with a 42-inch field-sizeable crossbar. Non-handed. ANSI A156.3 Grade 1. UL Listed. Fire-rated versions (88-F) carry 3-hour UL 10C rating. No electrified options by design: in correctional and behavioral health environments, electronic components at the device level are not appropriate.

Configurations: Rim (88/88-F), SVR (8827/8827-F), CVR (8847-F), Mortise (8875/8875-F).

94/95 INPACT Series: Recessed Push Pad

Applications: High-traffic openings where the push pad requires protection from cart, equipment, or deliberate impact damage.

Why: Recessed push pad design reduces impact exposure in environments where a standard protruding push pad would be repeatedly struck.

98/99 Series: Institutional Flagship

Applications: Schools, hospitals, universities, government buildings, any high-traffic institutional opening requiring the highest specification depth.

Why: The dominant institutional specification in North America. ANSI A156.3 2014 Grade 1. UL Listed for panic and fire exit hardware. Made in the USA. Five configurations: rim, SVR (9827/9927), CVR (9947), WDC (wide door cable), and the 9875/9975 mortise device using the 7500 mortise lock body.

Forward compatibility: A mechanical 98/99 specified today can be upgraded to full electrified access control years later without replacing the device body. This is why architects and security consultants default to the 98/99 on complex institutional projects with phased access control implementation.

Electrified options: The deepest catalog in the Von Duprin lineup: QEL, HD-QEL, MEL, Chexit, ELR, Allegion Connect, RX, RX2, WP-RX, LX, LX-RX, SS Signal Switch, electric power transfers, and more.

Guard-X 2670: Alarmed Secondary Exit

Applications: Secondary exits in restaurants, retail, grocery, drug stores, any commercial space needing unauthorized exit deterrence.

Why: Not a standard exit device with an alarm add-on. Purpose-built with a 100-decibel alarm, stainless steel deadbolt rated to 1,600 pounds, armed indicator light, and Schlage SC-1 cylinder. NFPA 101 compliant. UL Listed. 10-year mechanical warranty, 1-year electrical warranty.

Side-by-Side Comparison

Why Series Selection Affects Parts Sourcing for Life

Every series has its own parts tree. Components do not cross between series. A 78 Series arm does not fit a 33A/35A device. A 22 Series center case does not fit a 75 Series device. Specifying the wrong series at the project stage creates parts sourcing problems at every maintenance cycle for the full service life of the opening.

Security Parts organizes the complete Von Duprin exit device series comparison catalog by series and model, with interactive diagrams on every model page. The exit devices section covers every series in the same model-specific structure. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

The Von Duprin exit device series comparison starts with four decisions: fire rating, single vs double door configuration, stile width, and electrified options requirement. Those four answers eliminate most series immediately. The 98/99 for institutional depth and forward compatibility. The 22 for mid-range Grade 1 cost efficiency. The 33A/35A and 78 for narrow-stile aluminum and glass. The 88 for crossbar abuse resistance without electronics. The 55 for narrow-stile crossbar aesthetics. The Guard-X for alarmed secondary exits. Every series has its own non-interchangeable parts tree. Getting the series right at specification time is what keeps every future maintenance order, every parts replacement, and every code inspection on the correct path.

FAQs

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

 The 98/99 is the institutional flagship with the deepest electrified options catalog, five configurations, and Made in USA production. The 22 is mid-range Grade 1 for medium-traffic commercial at a lower specification cost.

When should I specify the 78 Series instead of the 33A/35A?

 Both fit narrow-stile aluminum and glass doors at 1-3/4 inch minimum stile width. Specify the 78 when a push pad is required. Specify the 33A/35A when a full-width touchbar is required or preferred.

Does the Von Duprin 88 Series support electrified access control? 

No. The 88 Series is mechanical-only by design. It is specified in correctional and behavioral health environments where device-level electronic components are not appropriate.

What is the 98/99 forward compatibility advantage? 

A mechanical 98/99 specified today can be upgraded to QEL, MEL, Chexit, Allegion Connect, or other electrified options years later without replacing the device body. This makes it the default institutional choice when phased access control is anticipated.

Are Von Duprin series parts interchangeable between models?

 No. Every series has its own non-interchangeable parts tree. A 78 Series arm does not fit a 33A/35A. A 22 Series center case does not fit a 75 Series. Series selection at specification time determines parts compatibility for the life of the opening.

Rim exit devices are the most widely installed panic hardware configuration in commercial construction, and the Von Duprin 98/99 Series is the institutional standard for that category. The 98 and 99 Series devices are certified to ANSI A156.3 2014 Grade 1, UL Listed for panic exit hardware and fire exit hardware, manufactured under ISO 9001 Quality Management System standards, and made in the USA. They are non-handed from the factory in most configurations, ship with a 299 rim strike standard, cover hollow metal doors with 86 or 161 cutouts, and support the deepest electrified options catalog in the Von Duprin lineup. Understanding what makes a rim device the right specification, and what makes it the wrong one, is what prevents the most common exit hardware specification error in commercial construction.

How a Rim Exit Device Works

The mechanism is simple by design. When a person presses the push bar, a lever arm inside the center case depresses and retracts the latch bolt from the rim strike pocket on the frame. When the bar is released, a return spring extends the latch bolt again. When the door swings shut, the beveled nose of the latch bolt rides over the strike lip and drops into the strike pocket automatically.

This simplicity is why rim devices dominate commercial construction. No rods penetrating the door floor. No mortise pocket cut into the door edge. The full mechanism sits on the face of the door, visible and accessible for maintenance without disassembly.

Fire-rated configurations remove the hex dogging function. On fire-rated openings, the latch must extend automatically every time the door closes. The "-F" suffix in the model number designates fire-rated configurations.

When Rim Is Right and When It Is Not

Rim is the correct specification for:

Single doors meeting a fixed frame. Paired doors with a center mullion, where each leaf latches to the mullion. Standard hollow metal commercial doors with 86 or 161 door prep cutouts.

Rim is the wrong specification for:

Double doors without a center post. When two active leaves must latch against each other at a center meeting point, a surface vertical rod (SVR) device adds top and bottom rod engagement for three-point latching. The 2227 SVR (22 Series), 9827/9927 SVR (98/99 Series), and 8827 SVR (88 Series) cover this application.

Applications requiring concealed hardware. When surface-mounted hardware is architecturally unacceptable, the concealed vertical rod (CVR) configurations route hardware inside the door.

Applications needing mortise lock security depth. The 98/9975 mortise exit device integrates the 7500 mortise lock body for maximum security at the door edge.

98 vs 99: The Only Difference That Matters

The 98 Series has a smooth mechanism case. The 99 Series has a grooved mechanism case. Every internal component is identical and fully interchangeable between the two. Every parts number that applies to a 98 rim device applies equally to a 99 rim device. The distinction is aesthetic only and produces no difference in performance, function, or Grade 1 certification.

Key Specifications Every Specifier Needs

ANSI certification: ANSI A156.3 2014 Grade 1 (the 2014 edition is the current standard, not the 2001 edition cited in older specifications).

UL listing: UL Listed for panic exit hardware and fire exit hardware. Fire-rated configurations carry a 3-hour UL 10C listing on single doors.

Non-handed status: The 98/99 rim device ships non-handed from the factory in most configurations. It becomes handed when ordered with SD (special dogging), -2 (double cylinder), or SS (signal switch) options.

Available finishes: US3, US3A, US4, US4A, US10, US26, US26D, US26D-AM Antimicrobial, US28, 313, 315, and 643E. The antimicrobial finish (US26D-AM) is specified in healthcare applications where touch surface hygiene is a design requirement.

Strike: 299 rim strike on non-fire-rated devices. 299F on fire-rated. The 299 measures 1-1/4 inches wide by 2-7/8 inches high with 2-1/8-inch slotted hole spacing.

Door lengths: 3-foot (36-inch) and 4-foot (48-inch) push bar lengths.

Trim Functions Available

The trim suffix in the model number determines outside hardware function:

• EO: Exit only. No outside operation. Most common on exterior egress-only openings.
• NL: Night latch. Key retracts latchbolt from outside. Uses rim cylinder and 1-1/4-inch mortise cylinder.
• NLOP: Night latch with pull required. Key retracts latch, then a pull action is required to open.
• TP: Thumbpiece. Key locks and unlocks outside thumbpiece.
• L: Lever. ADA-compliant outside entry function. Most common on accessible egress routes.
• DT: Dummy trim. Non-functional outside pull for aesthetic matching on inactive leaves.

Electrified Options on the 98/99 Rim Device

The 98/99 Series carries the most complete electrified options catalog in Von Duprin's lineup:

• QEL: Quiet electric latch retraction. Modular field-installable conversion. Silent outside entry without a key.
• HD-QEL: QEL with hex dogging retained. Allows mechanical dogging and electric latch retraction on the same device.
• MEL: Motorized electric latch retraction. Motor-driven for silent operation in noise-sensitive environments.
• Chexit: 15-second alarm-plus-delay for controlled egress and retail loss prevention.
• ELR: Standard solenoid-driven electric latch retraction.
• RX: Request to exit switch. Signals access control panel on egress activity.
• RX2: Double request to exit, two RX switches.
• WP-RX: Waterproof request to exit. Available with the OUT option for rim and surface vertical rod.
• LX: Latch monitor switch. Monitors latch bolt position for door status verification.
• LX-LC: Latch monitoring low current version.
• LX-RX: Combined request to exit and latch monitoring.
• SS (Signal Switch): Monitors both push pad and latch bolt simultaneously. Makes the latch bolt tamper-resistant. Rated up to 2.0 amp at 24VDC. Makes the device handed when specified.
• ALK: 9-volt battery-powered alarm exit kit.

Parts That Fail First on High-Cycle Openings

Dogging assemblies (post-1997 devices): Dogging shaft 090040 (long 5/32-inch hex key mandatory, 1/4-inch shaft depth). Dogging hook 090044. Dogging spring 090041. Pre-1997 devices use old-style components; part 050709 is the conversion kit.

Center case: Part 050021 replaces all earlier non-fire-rated 98/99 rim center cases, with approximately 40-year backward compatibility.

299 strike: Strike shift from door sag or frame movement produces latch alignment problems. Strike replacement is among the most common rim device service items.

Push bar end guide (090049): Reduces noise and friction at the push bar assembly end. Missed on most service visits until noise develops.

Sourcing 98/99 Rim Device Parts at Security Parts

Security Parts organizes the complete 98/99 Series parts catalog by model and configuration, with interactive diagrams on every page. The exit devices catalog covers every Von Duprin series with the same model-specific structure. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com.

Conclusion

Rim exit devices are ANSI A156.3 2014 Grade 1, UL Listed, manufactured to ISO 9001 standards, and made in the USA. The 98 and 99 Series are internally identical. The device is non-handed except when SD, -2, or SS options are specified. Twelve finishes are available including US26D-AM antimicrobial for healthcare. The HD-QEL option retains hex dogging while adding electric latch retraction. The SS Signal Switch monitors both push pad and latch bolt and makes the device handed. Every 98/99 rim device parts order starts with confirming the center case variant by trim function before the catalog opens.

FAQs

What is the ANSI grade of the Von Duprin 98/99 rim exit device?

 ANSI A156.3 2014 Grade 1. The 2014 edition is the current standard. UL Listed for both panic exit hardware and fire exit hardware.

When does the 98/99 rim device become handed?

When ordered with SD (special dogging), -2 (double cylinder), or SS (signal switch) options. Standard configurations without these options are non-handed.

What is HD-QEL on the 98/99 Series? 

Quiet Electric Latch Retraction with hex dogging retained. It allows mechanical dogging and electric outside entry on the same device simultaneously.

What is the SS Signal Switch option? 

It monitors both the push pad and the latch bolt, signals unauthorized use to the access control system, makes the latch bolt tamper-resistant, and is rated up to 2.0 amp at 24VDC. It also makes the device handed.

Are 98 and 99 Series parts interchangeable? 

Yes, completely. The 98 has a smooth case and the 99 has a grooved case. Every internal component is identical between the two.

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.

The Von Duprin 7500 parts manual covers the mortise lock that pairs with the Von Duprin 88 Series mortise exit device line. The 7500 itself is a field-reversible mortise lock with a non-handed auxiliary bolt for deadlocking, an adjustable-bevel faceplate, and field-selectable TP and K functions. The E7500 is the electrified variant with electric locking or unlocking options. The SS-7500 is the stainless steel build.

That's the short version. If you're pulling parts off a hardware schedule or troubleshooting a service call, the longer version is what determines whether you order the right component the first time. This guide walks through the 7500 mortise lock anatomy, function selection, exit device pairing, electric strike compatibility, and how to source replacement parts without misordering.

What the Von Duprin 7500 Mortise Lock Is

The Von Duprin 7500 is the mortise lock designed to operate as the inside locking mechanism for the Von Duprin 88 Series mortise exit device. The 88 Series is the panic hardware on the door. The 7500 is the mortise lock body that handles the latch and bolt work behind it. They're sold and specified together as a system on commercial doors that need both panic egress and mortise-lock security.

Three things make the 7500 unusual compared to a generic mortise lock. The lock is field reversible without removing it from the door, which cuts install and service time substantially. The auxiliary bolt is non-handed, which means it works on either swing direction. And the faceplate carries an adjustable bevel, so the lock can adapt to door edge angles without ordering a different SKU. Those three properties together are why the 7500 stays on spec sheets even as newer mortise hardware enters the market.

7500 vs E7500 vs SS-7500: Identifying the Variant You Have

The Von Duprin 7500 ships in three primary variants, and the parts manual breakdown is different for each one.

The standard 7500 is the mechanical mortise lock. No electrification, no monitoring switches. This is the variant on most older Von Duprin 88 Series installs.

The E7500 is the electrified version. It carries the same chassis as the mechanical 7500 but adds electric locking or unlocking through the outside trim. Two SPDT signals monitor trim condition and latchbolt status. Power options include 12V DC, 24V DC, and AC variants with available solenoid kits (SO12, SO24). The E7500 is what's specified on access-controlled commercial openings.

The SS-7500 is the stainless steel build. Same function set as the standard 7500 but with the corrosion-resistant body and faceplate. Common in coastal installs, food processing facilities, and any environment where the mortise lock has to survive humidity and washdown.

Pull the lock face off the existing door and read the model designation before ordering parts. The 7500, E7500, and SS-7500 share many components but not all of them. Cylinder housings, trim spindles, and latch assemblies cross. Solenoid assemblies, electrical kits, and monitoring switches are E7500 specific.

Function Options on the Von Duprin 7500

The 7500 ships with field-selectable functions, which is one of its strongest features for inventory and service. The two primary functions are TP (thumbpiece) and K (keyed). Function selection happens through a set screw in the mortise lock body. Turning the set screw down switches between TP and K function without disassembling the lock.

That field selectability matters when you're servicing a building with mixed openings. One stocked 7500 can be configured for either function at the door, instead of stocking two SKUs. For procurement teams managing replacement parts across a portfolio of buildings, this drops inventory complexity meaningfully.

The E7500 adds electric lock and electric unlock function variants on top of the mechanical function selection. The choice between electric lock (the trim is normally unlocked, locks when energized) and electric unlock (the trim is normally locked, unlocks when energized) is set at order, not field selectable.

Components in the Von Duprin 7500 Parts Manual

The 7500 mortise lock breaks down into these core component groups, listed in the order you'll typically encounter them during service:

Mortise lock case with internal mechanism. The lock body itself. Replaced as a complete unit on most failures.

Faceplate with adjustable bevel. Field replaceable. Bevel adjusts to door edge angle.

Auxiliary bolt (non-handed). Deadlocks the main latch when the door is closed. One of the highest-wear components on heavily cycled doors.

Main latchbolt. The latch that engages the strike. Stainless steel on most production runs.

Trim spindles and connecting hardware. Link the inside and outside trim to the lock body. Worn spindles cause loose trim feel and eventually lever droop.

Cylinder housing. Accepts the keyway cylinder. The 7500 typically takes a Schlage-prep mortise cylinder, which means common Everest 29 or Primus cylinders fit directly.

Set screw for function selection. Located in the lock body. Turns to switch between TP and K functions.

Solenoid assembly (E7500 only). Drives the electric lock or unlock mechanism. Solenoid power draw varies by voltage: roughly 0.38 amps at 12V DC, 0.19 amps at 24V DC.

Monitor switches (E7500 only). Two SPDT signals for trim and latchbolt status. Wired to the access control panel.

Strike pocket insert. Specified for 7500 mortise lock compatibility with Von Duprin 6212WF and similar electric strikes. Furnished with the strike, not the lock.

Compatible Exit Devices and Electric Strikes

The Von Duprin 7500 mortise lock was designed to work with the Von Duprin 88 Series mortise exit devices. That's the canonical pairing. The 8875-F mortise lock fire exit device pairs directly with the 7500 for UL-listed 3-hour fire door assemblies on single and double 4-foot by 8-foot openings.

For electric strike compatibility, the Von Duprin 6200 Series strikes are the matched pair. Specifically, the 6211, 6211AL, 6211WF, 6212, 6213, 6214, 6215, 6221, 6222, 6223, 6224, 6224AL, 6225, and 6226 strikes are factory-listed as 7500 mortise lock compatible. The 6210 strike is the direct replacement for legacy Von Duprin 3146 applications and also pairs with the 7500. The 6212WF includes a strike pocket insert specifically engineered for 7500 mortise lock mounting.

When sourcing an electric strike for a 7500 mortise lock door, confirm the strike compatibility chart on the strike's spec sheet before ordering. The mounting tabs and pocket dimensions differ between Von Duprin's own strike lines and surface-applied alternatives.

How to Identify a Von Duprin 7500 Before Ordering Replacement Parts

Three checks before placing a parts order. Each one prevents a return.

First, confirm it's a 7500 and not a 7400 or other Von Duprin mortise line. The 7500 family stamps the model number on the lock face. Remove the trim, look at the lock face for the model designation, and read it directly.

Second, identify the variant. Mechanical 7500, electrified E7500, or stainless SS-7500. The body finish gives you the SS variant immediately. The presence of wiring leads coming out of the lock body identifies the E7500.

Third, identify the function. TP function (thumbpiece trim) vs K function (keyed trim). Look at the existing outside trim. A thumbpiece-style trim is TP. A keyed lever or knob with no thumbpiece is K. If the function needs to change during service, the set screw inside the lock body switches it without ordering different parts.

Common Service Issues and Which Parts to Replace

Three failure patterns dominate Von Duprin 7500 service calls.

Auxiliary bolt wear. The deadlocking auxiliary bolt sees high cycle counts on heavily used doors and eventually loses spring tension or shows visible wear at the engagement face. Replace as a single component.

Trim spindle wear or loose lever feel. The spindle connecting outside trim to the lock body wears over time, particularly on doors that get pulled rather than pushed. The lever or thumbpiece develops play. Replace the spindle assembly rather than the full lock body.

E7500 solenoid failure. Most often traced to wrong voltage at the lock terminals, transient voltage from solenoid-based hardware on the same circuit, or simple end-of-life on a high-cycle door. Confirm voltage and transient suppression before replacing the solenoid. A motor that fails inside a year is usually an install problem, not a hardware defect.

How to Source Von Duprin 7500 Replacement Parts

For mechanical 7500 components, source by part type: faceplate, auxiliary bolt, latchbolt, trim spindle, cylinder housing. Each is available as an individual replacement. The Von Duprin parts catalog on Security Parts indexes by series.

For E7500 electrical components, confirm voltage (12V DC, 24V DC, or AC) before ordering. Solenoid assemblies are voltage-specific. Order the matching SO12 or SO24 kit for AC operation. Note that 16V DC and 28V DC solenoids are stocked as replacement parts only for existing legacy strikes, not new builds.

For complete 7500 mortise lock replacement, order by full SKU including function (TP or K) and finish. Stainless variants (SS-7500) carry their own ordering line. Cross-reference exit device compatibility with the Von Duprin 88 Series exit devices when replacing the lock as part of a system service.

For electric strike replacement matched to a 7500, the Von Duprin electric strike line carries the 6200 Series strikes that pair with the 7500 mortise lock. Confirm strike model number against the 7500 compatibility chart before ordering.

For configurations not visible online, call 845-935-0301. Two minutes of spec verification on the phone prevents the wrong-configuration return cycle on a service call that probably doesn't have those days to spare.

Frequently Asked Questions

What is the Von Duprin 7500 used for?

 The Von Duprin 7500 is a mortise lock designed to pair with the Von Duprin 88 Series mortise exit devices. It handles the latch and bolt work on commercial doors that need both panic egress hardware and a mortise lock body.

Is the Von Duprin 7500 field reversible?

 Yes. The 7500 mortise lock can be reversed for opposite hand without removing the lock from the door. The auxiliary bolt is non-handed, which means it operates correctly in either swing direction.

What's the difference between Von Duprin 7500 and E7500? 

The 7500 is the mechanical mortise lock. The E7500 is the electrified variant with electric locking or unlocking through the outside trim, plus two SPDT signals for trim and latchbolt monitoring. The E7500 ships in 12V DC, 24V DC, or AC configurations.

How do I switch between TP and K function on a Von Duprin 7500? 

Function selection is field-adjustable through a set screw in the mortise lock body. Turning the set screw down switches between TP (thumbpiece) and K (keyed) function without disassembling the lock.

Which electric strikes work with a Von Duprin 7500? 

The Von Duprin 6200 Series strikes are factory-listed as 7500 compatible. Specifically the 6210, 6211, 6212, 6213, 6214, 6215, 6221, 6222, 6223, 6224, 6225, and 6226 strikes. The 6212WF includes a strike pocket insert engineered for 7500 mortise lock mounting.

Is the Von Duprin 7500 fire rated?

 The 7500 mortise lock is used on UL-listed fire door assemblies when paired with the 8875-F mortise lock fire exit device, supporting 3-hour fire ratings on single and double 4-foot by 8-foot openings.

What voltage does the E7500 solenoid require? 

The E7500 ships in 12V DC, 24V DC, and AC variants. Power requirements are approximately 0.38 amps at 12V DC and 0.19 amps at 24V DC. AC operation requires the SO12 or SO24 solenoid kit.

Where can I source Von Duprin 7500 replacement parts? 

Security Parts stocks the Von Duprin 7500 mortise lock and component-level parts including auxiliary bolts, faceplates, trim spindles, cylinder housings, and E7500 solenoid kits. Call 845-935-0301 for configurations not visible online.

Closing

The Von Duprin 7500 mortise lock is one of the longest-running commercial mortise lines still on active service catalogs. It's on hardware schedules across institutional buildings, healthcare facilities, and K-12 schools that were built or renovated in the last twenty years. When a 7500 needs service, the parts manual breakdown above is what determines whether the right component gets ordered or whether the door stays out of service for an extra week.

Source it from a distributor that stocks both the 7500 mortise lock and the matched 88 Series exit devices on the same line. Security Parts has carried Von Duprin commercial hardware since 2001, with same-day shipping on stocked components and spec verification by phone at 845-935-0301 for configurations that need a second set of eyes.

Understanding electric strikes parts and diagrams saves facilities teams from a common and expensive problem: replacing an entire electric strike when only the solenoid has failed. Von Duprin's 6000 Series electric strike line, covering the 5100, 6100, 6200, and 6300 models, is the most widely installed commercial electric strike in North America. These devices are built to be field-serviceable, with the solenoid as the primary replaceable component. The Von Duprin 050240 solenoid kit fits every model in the 6000 Series at 24VDC (with 12VDC in 050237 and 16VDC in 050239), which means one stocked solenoid kit covers the most common failure across the entire product line. But accurate sourcing requires understanding the full component diagram, knowing the difference between fail-safe and fail-secure operation, and confirming the voltage and finish before ordering any finish-specific parts.

How an Electric Strike Works: The Four-Component System

An electric strike replaces a conventional strike plate in the door frame. Instead of a fixed pocket for the latch bolt, the electric strike uses a spring-loaded keeper (also called the lip or gate) that can either stay engaged to keep the door latched or release to allow the door to open without retracting the latch bolt. This is the essential distinction from an electric lock: the electric strike releases from the frame side, so the latch bolt on the door hardware does not need to move.

The four primary components visible in the Von Duprin 6000 Series diagram are:

Strike Body: The main housing that mounts into the door frame cutout. The strike body contains the solenoid, the keeper mechanism, the latch pocket, and the mounting hardware. Strike body dimensions are specific to the strike model and the frame prep. The 6100 and 6200 Series are designed for new construction applications. Retrofit applications may require frame modification when replacing a competitive or older Von Duprin strike.

Solenoid Assembly: The electromechanical component that drives the keeper release. When energized, the solenoid plunger moves, releasing the keeper so the door can swing open. On fail-safe strikes, the solenoid must be energized (power applied) to hold the keeper in the locked position. On fail-secure strikes, the solenoid must be energized to release the keeper.

The Von Duprin solenoid kits by voltage: 050237 (12VDC), 050239 (16VDC), 050240 (24VDC). All three fit every model in the 6000 Series. Note: 16VDC and 28VDC solenoids are sold only as replacement parts for existing strikes in the field. They are not specified for new installations. For AC power operation, the Von Duprin SO12 (12VAC) or SO24 (24VAC) rectifier kit converts AC to the DC the solenoid requires.

Keeper (Strike Lip or Gate): The pivoting component that the latch bolt rides over when the door closes and that either holds or releases the latch when the solenoid is energized or de-energized. The keeper on the 6000 Series is spring-loaded to return to the locked position when the solenoid de-energizes. This spring is a separate serviceable component in the 6000 Series refurbish kit.

Cover Plate and Mounting Hardware: The visible face plate that conceals the strike housing in the frame. Finish must match the installed hardware. Finish-specific items in the 6000 Series are designated with an "X in Finish column" notation in the parts manual, meaning the finish code must be specified when ordering.

Fail-Safe vs Fail-Secure: The Most Operationally Important Distinction in Electric Strike Parts

This distinction affects which solenoid behavior is correct for the installation and has direct code compliance implications for fire door and life safety applications.

Fail-secure operation: The door is normally locked. Power must be applied to unlock (release the keeper). When power is lost (power failure, fire alarm cutoff), the door remains locked. Fail-secure strikes are available for fire-rated openings. The Von Duprin 6100 fail-secure is specified FSE at time of order.

Fail-safe operation: The door is normally unlocked when powered. Power must be removed to lock (engage the keeper). When power is lost, the door unlocks. Fail-safe strikes are commonly used for life safety applications and are non-fire-rated. This is because a fire door must be able to latch under fire conditions, and a fail-safe strike that opens when power is cut would prevent latching during a fire event when building power may be compromised.

When the solenoid fails in a fail-secure installation, the door will typically remain locked regardless of any input signal. When the solenoid fails in a fail-safe installation, the door may fail open or may fail in an intermediate position depending on the spring return and keeper condition.

The entry buzzer (EB) option is available only with fail-secure strikes. It is installed in the frame in parallel with the strike circuit and provides an audible signal to the visitor when the door can be opened.

The Six Series in the Von Duprin Electric Strike Lineup

5100 Series: Standard commercial electric strike for rim exit devices on single doors and pairs. Designed for Von Duprin rim panic hardware applications specifically. Not for use with mortise or cylindrical locks.

6100 Series: Standard commercial electric strike for mortise locks and cylindrical locks. Available in fail-safe and fail-secure. Standard 24VDC. Optional 12VDC and AC operation. Power requirements: 12VDC at 0.38 amp, 24VDC at 0.19 amp. Compatible with a wide range of frame preps.

6200 Series: The high-security electric strike with ANSI/BHMA 156.5 Grade 1 certification and 1500-pound holding force rating. UL 294 Listed, UL 1034 Listed for burglary-resistant electric door strikes. Fire rated UL 10C to 3 hours on single doors, 90 minutes on pair doors with inactive leaf. Compatible with Schlage, Von Duprin, and Falcon cylindrical and mortise locksets as well as many other manufacturers' products. Available for new construction and retrofit applications. The 6200 Series can retrofit a number of competitive and older model Von Duprin electric door strikes.

6300 Series: The widest compatibility electric strike in the Von Duprin lineup, designed for applications where the specific lock manufacturer or model cannot be easily specified at time of order. Covers cylindrical, mortise, and panic hardware applications in a single platform.

J2 Series (6111, 6112, 6113): Specifically engineered for wood frame applications. The 6211WF is recommended on wood frames for new installations. For retrofit applications on wood frames replacing Folger Adam competitive strikes, the J2 Series maintains dimensional compatibility with legacy frame preps.

Monitor Strike Option: What It Adds

The monitor strike option adds a switch inside the strike body that monitors both latch bolt position (whether the latch is in the strike pocket) and lock status (whether the keeper is in the locked position). This allows the access control system to confirm that the door is both closed and latched, rather than just confirming that the strike released. Monitor strike configurations are designated "M" in the model number and require wiring for both the solenoid circuit and the monitor switch circuit.

The monitor option is specified in security-sensitive applications including government access control, healthcare, and financial institutions where door status verification is required by the access control specification.

The 6000 Series Refurbish Kit

Von Duprin produces a 6000 Series refurbish kit that contains the spring-loaded keeper, the pivot pin, and the mounting hardware needed to restore a worn or damaged 6000 Series strike body to full function without replacing the full unit. The refurbish kit is the correct maintenance approach when the keeper is worn, the spring return is weak, or the pivot pin is corroded, but the strike body housing and solenoid are otherwise functional.

The refurbish kit does not include the solenoid. If both the keeper mechanism and the solenoid are failed, the solenoid must be ordered separately alongside the refurbish kit.

Sourcing Electric Strike Parts Accurately

Security Parts organizes the complete electric strikes parts and diagrams catalog for Von Duprin 5100, 6100, 6200, and 6300 Series. Every series page carries component-level organization with interactive diagrams. The Von Duprin Von Duprin brand page covers the full electric strike lineup alongside exit devices and other Von Duprin hardware.

Two ordering notes specific to 6000 Series parts: finish-specific items require the finish code. Items without a finish designation ship in the manufacturer's standard finish, which may not match the installation. Second, 16VDC and 28VDC solenoids are replacement-only parts and cannot be ordered for new applications. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com for frame prep confirmation and lock compatibility questions before an order is placed.

Conclusion

The Von Duprin 6000 Series electric strike is a four-component system: the strike body, the solenoid, the keeper, and the cover plate. The solenoid kit in the correct voltage (050237 for 12VDC, 050239 for 16VDC, 050240 for 24VDC) fits every model in the series and is the most common single repair in the field. Fail-secure strikes are available for fire-rated openings. Fail-safe strikes are non-fire-rated. The 6200 Series carries a 1500-pound holding force and 3-hour UL 10C fire rating on single doors. The refurbish kit restores keeper and spring function without replacing the full unit. Sourcing correct electric strikes parts and diagrams starts with confirming the series, the voltage, the fail mode, and the finish before the order is placed. Security Parts stocks every 6000 Series component with same-day shipping and pre-order support at 845-935-0301.

FAQs

What is the Von Duprin 050240 solenoid kit? 

The 24VDC replacement solenoid for all Von Duprin 6000 Series electric strikes. Available in 12VDC (050237) and 16VDC (050239). Note: 16VDC is a replacement-only voltage not available for new installations.

What is the difference between fail-safe and fail-secure electric strikes? 

Fail-secure stays locked without power, unlocks when power is applied. Fire-rated strikes are fail-secure. Fail-safe stays unlocked without power, locks when power is applied. Fail-safe strikes are non-fire-rated and are used for life safety applications.

What is the holding force rating on the Von Duprin 6200 Series? 

1500 pounds, ANSI/BHMA 156.5 Grade 1. The 6200 Series carries UL 294, UL 1034 (burglary-resistant), and UL 10C (fire) listings with a 3-hour rating on single doors.

What does the 6000 Series refurbish kit include? 

The spring-loaded keeper, pivot pin, and mounting hardware for restoring a worn 6000 Series strike body. The solenoid is not included and must be ordered separately if the solenoid has also failed.

What is a monitor strike? 

An electric strike with an internal switch that monitors both latch bolt position (closed) and lock status (latched). Required in access control specifications where door status verification rather than just release signal confirmation is needed.

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.

Quick Answer

Von Duprin panic bar parts are series-specific and in many cases generation-specific within the same series. Before ordering any component, confirm four things: