Back door lock issues

[Nightsky224]

Out of the blue we can no longer open the back door when it is unlocked by just using the handle.
We have to also turn the key to depress the latch further. Not sure if the warm weather has affected it but any ideas - here is a video to show

 

[Nightsky224]

Just to add I’m confident enough to take it apart, cylinder out etc but not sure what part I should be replacing etc

 

[Nightsky224]

Just a bump incase anyone has any ideas

 

[JohnD]

Open the door. Does the mechanism now operate correctly?

 

[Nightsky224]

Open the door. Does the mechanism now operate correctly?

When the door is shut but unlocked I can not open the door unless I turn the key as in the video

 

[crank39]

Pulling the handle down should retract the latch completely in, seeing as it isn't usually means there's an internal failure inside the gearbox somewhere, the gearbox is the main part of the locking mechanism and sits inside the plastic behind the handles, I think yours is an 'ERA' make looking at the latch, just under the latch there should be a black plastic piece that could say ERA on it, it may have other names on it as they're made under licence but it's usually an ERA or one of others, gives you a starting point. With these the gearbox can be separated and replaced so it saves you having to replace the complete mechanism, just Google ERA multi point lock, for a pvc door it's likely to be a 35mm backset x 92mm PZ but do check first

Gearbox should be around £20 to £30

 

[JohnD]

I asked to open it, because this would show if the latch or bolt were binding with the door shut. This is a common cause with ordinary wooden doors

 

[crank39]

It shows in the video that the latch isn't retracting fully when the handle is operated with the door open so it's not binding on anything