Faults with locks

There are two types of locks that we use in the majority of our properties, they are:

  • Mortise locks
  • Cylinder locks

What does your key look like?
If it is a common key shape, it is most likely to be a Mortise lock. Some cylinder locks are also Mortise locks but with a separate cylinder, for example double-glased doors.

Common faults with a Mortise lock and key
The key will not go in:

  • Are you using the right key?
  • Is it a new key? If so, it could be the wrong size.
  • Is anything blocking the keyhole? Can you clear it?
  • Some locks use a small metal curtain for locating the key, this can sometimes turn when the key is removed; it can be easily turned back with a small screwdriver.
  • Most ERA brand locks use this mechanism.

The door will not lock or unlock:

  • Does the lock work when the door is open? If so, the keep on the door frame may need to be adjusted (the keep is the metal plate attached to the door frame that the lock goes into).
  • If the door is open, but the lock still does not work, the lock may have failed or seized. If possible, spray some WD40 (not oil) into the lock and try turning the key gradually back and forward a few times. If this does not work the lock has failed and will need to be replaced.

The latch does not work:

  • This usually means that the spring has broken inside the lock. You should still be able to lock the door as the bolt is usually separate. Please note that the spring that needs to be replaced cannot be bought separately, so the lock will need to be replaced.


The key is too stiff to turn:

  • Is the key old? If so, try another key.
  • Sometimes if the key is too stiff to turn, it can be a sign that the lock is seizing; try to lubricate with some WD40. Please note that if the lubrication does not help it may be that the lock is starting to fail and will need to be replaced.

Cylinder locks
Cylinder locks are usually fitted onto the surface of the door. They are commonly referred to as rim locks, Yale locks or deadlocks. You can tell if you have a cylinder lock by looking at your key.


Common faults with a cylinder lock and key
The key will not go in:

  • Are you using the right key?
  • Is it a new key? If so, it could be the wrong sixe.
  • Is anything blocking the keyhole? Can you clear it?


The key just turns in the lock:
The cylinder has failed or the lock body has come loose on the inside.
Was the key bent or cracking? If so, it is your responisibility to replace the key.


The key is turning too far when locking, so the key cannot be removed:
The cylinder has failed. This is a common fault with double glazed doors.

The lock body is loose on the inside so the key will not work:
Can you tighten this yourself?

The cylinder is loose on the door:
Would you be able to take the lock body off and tighten the cylinder?


Multipoint locks
Multipoint locks work off a cylinder and are bolted into the frame. They are commonly found in double glazed doors. As this lock is a combination of both a Mortise and a cylinder lock, they share all the same common faults and a few of their own.


Common faults with Multipoint locks
The multi-bolts are not working:

  • If the bolts will not move at all when the handle is lifted, the lock has failed and needs to be replaced.
  • If the bolts will work when the door is open, the ‘keeps’ need to be adjusted. The ‘keeps’ are the metal plates that the bolt goes into which are attached to the door frame.
  • The latch will not work and the handles droop. As the majority of multipoint locks are sealed units and cannot be stripped down, this fault usually means that the lock needs to be replaced.

If you have any concerns about any of the services in your home, please call us on 020 8801 1117. We are here to help.