A customer in Woking got in touch because the uPVC front-door multipoint lock was becoming unreliable and increasingly difficult to secure.
When I tested the mechanism on site, the cause became clearer. The locking hooks were only travelling about halfway, which meant they could not engage far enough for the door to lock properly.
I removed the complete multipoint system and tried a thorough lubrication first in case the mechanism could be recovered without replacing parts.
Unfortunately, the fault remained.
I had the correct gearbox in van stock, so I replaced the failed centre case and rebuilt the system.
After refitting and testing the mechanism, the hooks were travelling through their full movement again and the front door could be locked normally.
