The gearbox is an essential part of the locking mechanism found in the door.
Double glazed door lock barrel.
To change a upvc door lock start by unscrewing the retaining screw which is located on the faceplate on the side of the door.
So all you would need to do is find the screw that holds the barrel of the lock in place and tighten it.
Then insert the key into the lock and turn it about 10 degrees to line up the inner latch of the lock with the body of the lock.
Xfort thumb turn euro cylinder lock 50t 50 100mm euro door barrel lock with 3 keys anti bump anti drill anti pick door lock with key high security for wooden metal upvc and composite doors.
If measuring a dl30 3 star anti snap door lock do remember the outer size is the anti snap size so is not a reversible size.
Replacing a euro cylinder or upvc door lock a simple guide from www fastkeys co uk additional info step 1.
Front door handles in white can be used on double glazed doors.
Open front door to reveal the face of the lock.
Measure from the end of the euro cylinder lock barrel to the centre of the screw hole each side.
4 4 out of 5 stars 65.
This will tighten the loose door handle and if done correctly your upvc door should be locking correctly and working again with no issues.