Why Is a Fire Door Closer Too Slow or Too Fast?

Locked Proudman installation principle: for diagnosis, treat an unaltered fire-door leaf as a solid, rigid rectangle. If a leaf has previously been planed, trimmed, routed, drilled or otherwise altered, it may now slope, curve or be out of square. Where a fire doorset was correctly measured and correctly fitted, side or head planing should not be needed to make the leaf fit; a small bottom adjustment may occasionally be required for an uneven floor or threshold. Always diagnose the complete doorset before altering one component. The symptom The door closes very slowly, accelerates through part of the movement, slams, or changes speed after repeated adjustment. First separate setting from resistance A speed control changes the closer's behaviour, but mechanical resistance from the doorset can make a correctly adjusted closer appear slow or inconsistent. Check hinges, seals, latch, frame and floor…