Mr Fizzion wrote:

I already took the door out and removed the screws at the sides.
However I am not too sure about how to remove the bottom part of the
frame as it seems to require a fair amount of force to move it down.
Shall I just carry on pushing?!

I did this once for my FIL. There was a hole in the inside of the sash
that led to an adjuster on the side of the roller mechanism. An alan key
could be inserted to "wind up" (or down) the mechanism. So removal of
the sash simply involved retracting the exiting wheels into the sash
which then enabled it to be lifted out of the frame from the bottom.
Replaced the broken roller, put it back in the frame and then lowered
the wheels onto the frame rail. This both fixed the door in place and
also raised it so that it was running freely on the rollers.


--
Cheers,

John.

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