In recent sessions with the Compass Omega 544 we have found the lock mechanism becoming increasingly difficult to lock and unlock. Latterly my wife has not been able to do either as the effort required was too great. To be honest the mechanism has been difficult from new.
Eureka!! I have a solution. I tried applying WD40 etc but to no avail and in the end I dismantled the lock mechanism. The centre of the lock depends on a barrel which is held in place with a split spring washer with two 'corrugated spring washers' behind forming spacers. With time and wear the mechanism is subject to too much pressure from the two spring washers and even the inner door lock lever becomes resistant to movement and as the key has to overcome this resistance it becomes even more difficult to lock/unlock from the outside. Today I removed one of the spring washers and the system is much easier to operate by both of us and remains secure. The Elddis range is almost a dead ringer for the Compass range and the door lock mechanism is identical. I hope this helps.
That's good to know, thank you. We have just got a Compass and the lock is a b*gger which I just put down to old age but I will get the OH to have a fiddle with it now.
The problem I had was not with the key lock mechanism rather the inner door plastic handle mechanism. The barrel in question is attached to this door lever. Sorry, I should have taken a picture of it while it was apart.