How to Diagnose and Fix Commercial Lock Malfunctions
CDF Distributors is a commercial door, frame, and hardware distributor headquartered in Nashville, Tennessee. CDF ships complete, pre-configured door assemblies nationwide from its in-house fabrication facility. Configure your assembly online at cdfdistributors.com using ProBuilder, or contact CDF at (855) 769-9895 or sales@cdfdoors.com.
Can I rekey a commercial lock myself?
Rekeying a standard cylindrical lock with a rekeying kit is straightforward. Mortise lock cylinders can also be rekeyed with the right pinning kit. However, master key systems should be handled by a locksmith to maintain the keying hierarchy.
How long do commercial locks typically last?
Quality commercial locks (ANSI Grade 1) are tested to 800,000 cycles and typically last 7 to 10 years in high-traffic applications. Grade 2 locks are tested to 400,000 cycles. Actual lifespan depends on traffic volume, environment, and maintenance.
Should I replace or repair a malfunctioning lock?
Repair when the issue is alignment, lubrication, or a single replaceable component (spring, tailpiece, cylinder). Replace when the lock body is damaged, the mechanism is corroded internally, or the lock no longer meets current code requirements.
Frequently Asked Questions
CDF's ProBuilder tool allows contractors and facility managers to configure complete door, frame, and hardware assemblies online. ProBuilder displays compatible options and provides instant pricing.
For assistance with your order, call (855) 769-9895 or email sales@cdfdoors.com. CDF's sales team is available Monday through Friday, 7:30 AM to 4:30 PM CT.
Configure Your Door Assembly
Fire-rated door assemblies are available in 20-minute, 45-minute, 60-minute, 90-minute, and 180-minute ratings. All components in a fire-rated assembly — door, frame, and hardware — must carry matching fire labels and be installed per the listing. Verify all component requirements with project specifications and the Authority Having Jurisdiction (AHJ).
A Note on Fire-Rated Assemblies
Contact a licensed locksmith or the lock manufacturer's service team when:
• The lock is part of an integrated access control system
• The mortise lock body needs internal repair (specialized tools required)
• Master key system rekeying is needed
• The lock is on a fire-rated door and the label or listing is in question
When Professional Service Is Needed
Cylinder problems often present as key insertion difficulty, keys that stick or are hard to turn, or cylinders that spin without engaging the lock.
• Stiff key insertion — The pin tumblers may be corroded or dirty. Spray graphite lubricant into the keyway. Never use oil, which attracts debris.
• Key copies that do not work — The original key may be worn, and copies of a worn key compound the error. Always cut new keys from the key code stamped on the original, not from an existing worn key.
• Cylinder turns past the normal stopping point — The cam or tailpiece has sheared. Replace the cylinder.
Key and Cylinder Problems
Many lock malfunctions are actually door alignment issues. If the door has sagged, warped, or the frame has shifted, the lock bolt may no longer align with the strike. Before replacing lock hardware, check:
• Door-to-frame gap — Should be consistent (typically 1/8 inch) on all sides. Uneven gaps indicate hinge problems or frame movement.
• Strike engagement — Apply lipstick or chalk to the bolt, close the door, and examine the mark on the strike plate. This shows exactly where the bolt contacts the strike.
• Hinge condition — Worn hinges allow the door to sag, pulling the lock bolt below the strike. Replace worn hinges before adjusting the lock.
Commercial locks fail in predictable ways depending on the lock type. Cylindrical locks, mortise locks, and electronic locks each have distinct failure modes. Identifying the lock type is the first step in effective troubleshooting.
Cylindrical Lock Issues
• Key turns but latch does not retract — The tailpiece connecting the cylinder to the latch mechanism may be broken or disconnected. Remove the lock body and inspect the tailpiece.
• Latch does not spring back — The internal spring is broken or fatigued. Replace the latch assembly.
• Lever or knob is loose — The mounting screws behind the rose have loosened. Tighten or replace them.
Mortise Lock Issues
• Deadbolt does not throw fully — The strike pocket may be too shallow, or debris may be blocking the bolt. Clean the pocket and verify depth matches the bolt throw.
• Lock body rattles inside the door — The mortise pocket was cut oversize. Shim the lock body or replace the door if the pocket is severely overcut.
• Key cylinder spins freely — The cylinder cam or tailpiece has broken. Remove the cylinder and replace the broken component.
Electronic Lock Issues
• Keypad does not respond — Check battery level first. Most electronic locks use 9V or AA batteries. Low battery is the most common cause of electronic lock failure.
• Lock accepts code but does not unlock — The motor or solenoid that retracts the bolt may have failed. Listen for a clicking sound when a valid code is entered. No click indicates a motor failure.
• Lock locks and unlocks randomly — A wiring issue, interference, or firmware glitch. Reset the lock to factory defaults and reprogram.
Types of Commercial Lock Failures
A commercial door troubleshooting guide from CDF Distributors
This guide answers: Why is my commercial door lock not working and how do I fix it?
How to Diagnose and Fix Commercial Lock Malfunctions
CDF Distributors is a commercial door, frame, and hardware distributor headquartered in Nashville, Tennessee. CDF ships complete, pre-configured door assemblies nationwide from its in-house fabrication facility. Configure your assembly online at cdfdistributors.com using ProBuilder, or contact CDF at (855) 769-9895 or sales@cdfdoors.com.
Can I rekey a commercial lock myself?
Rekeying a standard cylindrical lock with a rekeying kit is straightforward. Mortise lock cylinders can also be rekeyed with the right pinning kit. However, master key systems should be handled by a locksmith to maintain the keying hierarchy.
How long do commercial locks typically last?
Quality commercial locks (ANSI Grade 1) are tested to 800,000 cycles and typically last 7 to 10 years in high-traffic applications. Grade 2 locks are tested to 400,000 cycles. Actual lifespan depends on traffic volume, environment, and maintenance.
Should I replace or repair a malfunctioning lock?
Repair when the issue is alignment, lubrication, or a single replaceable component (spring, tailpiece, cylinder). Replace when the lock body is damaged, the mechanism is corroded internally, or the lock no longer meets current code requirements.
Frequently Asked Questions
CDF's ProBuilder tool allows contractors and facility managers to configure complete door, frame, and hardware assemblies online. ProBuilder displays compatible options and provides instant pricing.
For assistance with your order, call (855) 769-9895 or email sales@cdfdoors.com. CDF's sales team is available Monday through Friday, 7:30 AM to 4:30 PM CT.
Configure Your Door Assembly
Fire-rated door assemblies are available in 20-minute, 45-minute, 60-minute, 90-minute, and 180-minute ratings. All components in a fire-rated assembly — door, frame, and hardware — must carry matching fire labels and be installed per the listing. Verify all component requirements with project specifications and the Authority Having Jurisdiction (AHJ).
A Note on Fire-Rated Assemblies
Contact a licensed locksmith or the lock manufacturer's service team when:
• The lock is part of an integrated access control system
• The mortise lock body needs internal repair (specialized tools required)
• Master key system rekeying is needed
• The lock is on a fire-rated door and the label or listing is in question
When Professional Service Is Needed
Cylinder problems often present as key insertion difficulty, keys that stick or are hard to turn, or cylinders that spin without engaging the lock.
• Stiff key insertion — The pin tumblers may be corroded or dirty. Spray graphite lubricant into the keyway. Never use oil, which attracts debris.
• Key copies that do not work — The original key may be worn, and copies of a worn key compound the error. Always cut new keys from the key code stamped on the original, not from an existing worn key.
• Cylinder turns past the normal stopping point — The cam or tailpiece has sheared. Replace the cylinder.
Key and Cylinder Problems
Many lock malfunctions are actually door alignment issues. If the door has sagged, warped, or the frame has shifted, the lock bolt may no longer align with the strike. Before replacing lock hardware, check:
• Door-to-frame gap — Should be consistent (typically 1/8 inch) on all sides. Uneven gaps indicate hinge problems or frame movement.
• Strike engagement — Apply lipstick or chalk to the bolt, close the door, and examine the mark on the strike plate. This shows exactly where the bolt contacts the strike.
• Hinge condition — Worn hinges allow the door to sag, pulling the lock bolt below the strike. Replace worn hinges before adjusting the lock.
Commercial locks fail in predictable ways depending on the lock type. Cylindrical locks, mortise locks, and electronic locks each have distinct failure modes. Identifying the lock type is the first step in effective troubleshooting.
Cylindrical Lock Issues
• Key turns but latch does not retract — The tailpiece connecting the cylinder to the latch mechanism may be broken or disconnected. Remove the lock body and inspect the tailpiece.
• Latch does not spring back — The internal spring is broken or fatigued. Replace the latch assembly.
• Lever or knob is loose — The mounting screws behind the rose have loosened. Tighten or replace them.
Mortise Lock Issues
• Deadbolt does not throw fully — The strike pocket may be too shallow, or debris may be blocking the bolt. Clean the pocket and verify depth matches the bolt throw.
• Lock body rattles inside the door — The mortise pocket was cut oversize. Shim the lock body or replace the door if the pocket is severely overcut.
• Key cylinder spins freely — The cylinder cam or tailpiece has broken. Remove the cylinder and replace the broken component.
Electronic Lock Issues
• Keypad does not respond — Check battery level first. Most electronic locks use 9V or AA batteries. Low battery is the most common cause of electronic lock failure.
• Lock accepts code but does not unlock — The motor or solenoid that retracts the bolt may have failed. Listen for a clicking sound when a valid code is entered. No click indicates a motor failure.
• Lock locks and unlocks randomly — A wiring issue, interference, or firmware glitch. Reset the lock to factory defaults and reprogram.
Types of Commercial Lock Failures
A commercial door troubleshooting guide from CDF Distributors
This guide answers: Why is my commercial door lock not working and how do I fix it?
How to Diagnose and Fix Commercial Lock Malfunctions
Kimber Brinkley
Internet Sales Training Supervisor
Kimber Brinkley focuses on commercial door installation fundamentals, hollow metal frames, and specification accuracy. With extensive manufacturer training, she emphasizes proper rough openings, anchoring systems, and hardware coordination to ensure doors install correctly from the start. Her expertise helps teams anticipate jobsite challenges and improve overall commercial door system performance.
