What Is Involved In Replacing A Worn Barrel Lock Mechanism On A uPVC Door?

[Tobermory]

The barrel mechanism in the lock on our back door catches / sticks a little sometimes. I have oiled it but this does not seem to have improved the movement. So I think it is time to replace the lock.

I have never done anything to one of these multi point locking mechanisms before. Should it be fairly simple to obtain a replacement barrel mechanism and fit it or am I underestimating the extent of the work required?

These are some images of the existing mechanism:

 

[PrenticeBoyofDerry]

They are easy enough to remove and replace. If replacing I would opt for a ABS (high security lock) a little bit more expense but they are not scum friendly.

Anyway removing is best done with the key in the cylinder, (sometimes you have to remove the handle plate, but not always).
So remove the picture below the lock in picture 2, then with key in place and in unlocked position a little jiggling about and the cylinder should pull through.
It needs to be replaced be the same sized lock, as the do come in different lengths. There is generally some marks on the barrel indicating this, but keep some one home and take a trip to a local ironmongers/locksmith with the cylinder, note which end of the barrel is the external end, as this will be important if purchasing a security lock.
Replacing is the same in reverse, but make sure you have it the right way round (in/exteranlly)

 

[Gazman16]

Can you explain the problem you are having a little more? The barrel or cylinder is just the bit that the key goes into.

What is sticking? The key, The latch or is it just locking and unlocking the door thats getting a bit stiff? This may just mean the door needs adjusting. Try locking and unlocking the door several times while the door is open, If there is no sign of stiffness this way then its just some adjustments to the door that you need.

Upgrading to an ABS cylinder may be a good idea too depending on your area, Those old cheap cylinders can be broken into in under a minute.

 

[foxhole]

If it sticks the screw holding it in position may have worked loose, worth checking before you replace, simple fix. [should be no movement in lock when keyed, a 1mm movement is enough to cause it to stick.]