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.

About CDF Distributors

What is the most common cause of a door not latching?

The most common cause is closer adjustment. The latching speed (final 10-15 degrees of closing travel) may not have enough force to compress the latch bolt against the strike. Adjust the latching speed valve on the closer before investigating other causes.

How do I determine if a door is warped?

Hold a straightedge (or a long level) against the lock edge of the door from top to bottom. If the straightedge does not make continuous contact, the door is warped. Warpage exceeding 1/4 inch in a 7-foot door typically prevents consistent latching and may require door replacement.

Can I lubricate commercial door hinges with WD-40?

WD-40 is a solvent and temporary lubricant, not a long-term hinge lubricant. Use a lithium-based or PTFE-based lubricant for commercial door hinges. Apply lubricant to the hinge pin and knuckle, then work the door through its full swing several times to distribute the lubricant.

What should I do if the door closer is leaking fluid?

A leaking closer cannot be repaired in the field. The hydraulic fluid loss will cause the door to close uncontrollably fast, which is a safety hazard. Replace the closer immediately. Do not continue using a door with a leaking closer.

When should a door be replaced rather than repaired?

Replace the door when: warpage exceeds 1/4 inch, the fire label is missing and cannot be field-relabeled, the core is compromised (delamination, moisture damage), hardware preps are enlarged beyond repair, or the door no longer fits the frame after all adjustments have been attempted.

Frequently Asked Questions

CDF's sales team can identify replacement components that match your existing preps. Use ProBuilder at cdfdistributors.com to configure replacement hardware, or contact CDF for assistance with troubleshooting and component identification.

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

CDF's sales team can help identify replacement components for troubleshooting resolution. ProBuilder ensures replacements match existing preps — provide the existing hardware manufacturer, model, and function, and CDF will identify a compatible replacement. For hardware that is no longer manufactured, CDF can recommend current alternatives that fit existing preps.

CDF Replacement Component Support

Unusual noises during door operation indicate a mechanical issue that will worsen if not addressed.

• Squeaking or squealing — lubricate hinge pins with a non-petroleum-based lubricant; check for metal-on-metal contact between the closer arm and bracket

• Clicking or popping — check the closer arm pivot points for wear; check the latch bolt for intermittent contact with the strike

• Grinding — check hinge knuckle for debris or corrosion; check the closer mounting screws for looseness

• Whistling — check weatherstripping contact; air passing through gaps at high velocity creates a whistle sound

• Rattling — check the door for looseness in the frame; verify the latch bolt fully engages the strike when closed

• Slamming — adjust the closer latching speed; verify the backcheck valve is functioning

Problem: Unusual Noises

Excessive gaps between the door and frame allow air, sound, and light passage. In fire-rated assemblies, excessive gaps are a code violation. The following checks identify the cause.

• Check hinge wear — worn hinges allow the door to drop, creating a larger gap at the top and smaller gap at the bottom on the lock side

• Check frame movement — the frame may have shifted from its original anchoring position, especially in settling buildings

• Check door sag — sagging creates uneven gaps; close the door and measure gaps at three points on each edge

• Check for missing weatherstripping — weatherstripping fills minor gaps; if it has been removed or has deteriorated, gaps become visible

• Check for door shrinkage — wood doors can shrink in dry conditions, creating uniform gaps on all edges

• Check shim condition — shims that have compressed or fallen out allow the frame to shift

Problem: Excessive Gaps

A lock that does not engage may be a hardware problem, an alignment problem, or a door fit problem.

• Check strike alignment — close the door slowly and observe where the latch bolt contacts the strike; adjust the strike if misaligned

• Check latch projection — the latch bolt must project far enough to engage the strike; some locksets have adjustable latch throw

• Check door warpage — hold a straightedge against the lock edge of the door; warpage of more than 1/4 inch can prevent latching

• Check the lockset mechanism — turn the lever/knob and watch the latch bolt; it should retract smoothly and snap back when released

• Check the deadbolt alignment — for deadbolts, the bolt must align with the strike; a sagging door shifts the bolt away from the strike

• Check key operation — if the key turns but does not engage the lock, the cylinder may be worn or the tailpiece connection may be loose

Problem: Lock Does Not Engage

A door that sticks or binds during operation usually has a physical interference between the door and frame. The following checks identify the source.

• Check frame plumb — an out-of-plumb frame causes the door to contact the frame at different points during the swing

• Check hinge screws — loose hinge screws allow the door to shift, causing intermittent binding

• Check for seasonal expansion — wood doors expand in humid conditions; this is the most common cause of seasonal binding

• Check hinge pin condition — worn or corroded hinge pins increase friction

• Check for paint buildup on edges — multiple coats of paint can reduce clearances enough to cause binding

• Check for debris in the hinge — small particles between hinge leaves prevent full closure of the knuckle

• Check closer arm for interference — the closer arm may be contacting the frame or soffit during operation

Problem: Door Sticks or Binds

A door that does not close fully is the most common commercial door complaint. The following checks identify the cause, ordered by likelihood.

• Check closer adjustment — the latching speed valve may be set too low to overcome the latch resistance

• Check closer arm connection — verify the arm is securely attached at both the closer body and the bracket

• Check hinge alignment — a sagging door (worn top hinge) changes the door's relationship to the strike

• Check strike alignment — the latch bolt must align with the strike opening; misalignment prevents latching

• Check threshold interference — the door sweep or bottom edge may be catching on the threshold

• Check for air pressure differential — HVAC systems can create pressure that resists door closing on exterior doors

• Check closer fluid — if the closer closes at full speed with no resistance, the closer may have lost hydraulic fluid and needs replacement

Problem: Door Does Not Close Fully

Commercial door problems fall into five categories: the door does not close, the door sticks or binds, the lock does not engage, there are excessive gaps, or the door makes unusual noises. This checklist provides a systematic diagnosis path for each problem category. Start with the most common cause and work through each check until the problem is identified.

For each problem, the checks are ordered from most likely to least likely cause. Complete each check before moving to the next.

Systematic Troubleshooting Approach

Systematic diagnosis and resolution steps for common commercial door operational problems.

This guide answers: What Should You Check When a Commercial Door Is Not Operating Correctly?