Hi. My UPVC front door sometimes doesn't lock. I can lift the handle and turn the key to the locked position, but most off the time just pushing the handle back down opens it. If I push the handle up hard it does eventually lock, but it is something that confuses people not familiar with the issue and the door is sometimes effectively left unlocked. (This is rare and we do have an alarm, so don't go trying to find out my address to burgle me - 
).
I'm guessing there is some sort of cam somewhere in the mechanism which pushes the latches into place which has maybe worn, so doesn't push them into position enough. I replaced the lock in case the cam on that was the issue, but it made no difference.
The mechanism isn't stiff and it doesn't seem to be an alignment issue.
What could be the issue and can I fix it myself?
Many thanks.
). I'm guessing there is some sort of cam somewhere in the mechanism which pushes the latches into place which has maybe worn, so doesn't push them into position enough. I replaced the lock in case the cam on that was the issue, but it made no difference.
The mechanism isn't stiff and it doesn't seem to be an alignment issue.
What could be the issue and can I fix it myself?
Many thanks.
