Upvc gearbox failure most common.
Upvc door lock stuck open.
Problem with lock cylinder.
Definitely not the fault here was the multipoint mechanism this is the long locking strip in the edge of the door and in this case the gearbox the center case in the middle of the locking strip i carry most multi point gearboxes so it was simply a case of replacing the part in the door.
Especially if your upvc door lock mechanism is sticking it s usually down to the fact that you have an old door which needs replacing.
Upvc door won t lock even when open.
There are many types of multi point lock on the market used in upvc composite doors so hard to tell without looking most likely a fault with multi point and could be any of the components deadbolt shoot bolt etc etc undoing hinge screws may work if you can get to them flag hinge which is unlikely if they have a grub screw holding the cover in place pins could be removed if a older door.
If your upvc door won t lock even when still open this is usually because of the following reasons.
Broken keys rust and misalignment are the most common causes of jammed door locks and doors that just won t open.
If your upvc window lock is broken it is wise to ask a professional window fitter to take a look at it most upvc windows are fitted with an espag lock which is operated using the handle.
A gap between the window and the frame could also lead to draughts and damp.
Upvc gearbox failure or multipoint lock damage.
Door lubrication is required.
If your upvc window is open and you are unable to lock it your home is not secure.