About this service
If your uPVC door handle spins loosely, the key turns but nothing engages, or you have to lift and shoulder the door to lock it, the multipoint lock mechanism (gearbox) has failed. First Line Locksmiths repairs and replaces uPVC door lock mechanisms across West London, Berkshire and Buckinghamshire, matching the gearbox by backset, PZ centre and hook layout so the door locks smoothly again without replacing the whole door.
What's included
- Multipoint gearbox, hooks, rollers, keeps and shootbolts replaced
- Handle-spinning, jammed and misaligned doors realigned the same day
- Fensa-style hinge and keep adjustment included with every repair
- Common makes stocked: Yale, Fullex, GU, Winkhaus, Maco, Avocet, Millenco, Lockmaster
- Upgrade to a TS007 3-star anti-snap cylinder while we're there
Our process
Diagnose the failure
We identify whether it's the gearbox, cylinder, hinges or keeps — a lot of 'broken locks' are just alignment.
Measure the mechanism
Backset, PZ centre, faceplate width and hook pattern measured so the replacement matches exactly.
Fit and align
New mechanism fitted, keeps adjusted and hinges toed-and-heeled so the door closes without lifting.
Test and guarantee
Full lock and unlock cycle tested from both sides, with a 12-month guarantee on parts and labour.
Where we cover
We provide upvc mechanism repair across West London, Berkshire and Buckinghamshire, including:
