Fire door won't close and latch — diagnosing the cause

How to test it correctly

Release the door from roughly 5 degrees, then 45, then fully open. It should close and latch each time without a push. The near-closed test is the one that catches most failures, because a closer with insufficient latching action will manage from wide open but stall in the final inches.

Causes, in the order we usually find them

• Closer latching speed or power set too low, often after someone adjusted it to stop the door slamming.
• Hinges worn or the leaf dropped, so it catches on the frame or threshold.
• Latch and keep out of alignment after frame movement.
• New carpet or matting increasing floor drag.
• Air pressure from mechanical ventilation, stairwell effects or an open external door working against the closer.

Why cranking the closer up is the wrong fix

Increasing closer power to force a dragging door shut makes the door heavier to open. Where accessibility matters — care settings, schools, public-facing premises — that creates a different problem. The correct approach is to remove the resistance first and then set the closer to the lowest power that still latches reliably.

What a remedial visit covers

We test each door across its swing, adjust or replace closers and hinges, realign latches and keeps, address threshold interference, and re-test. Every door is recorded with its before and after condition so your fire door records stay current.