We are having a problem with the power shower.
I have electrically disconnected both ends of the supply cable and
removed the control knobs, but the plumbing part of it has me beat.

The shower case is a push fit onto the hot and cold copper pipes and
then screwed onto the wall. I have removed the three screws that are
shown in the paperwork and I read that I should push back 2 grey collars
and the case should come off the pipes. No matter how I push the collars
I can't get the case off the pipes.
Is there a knack, or have the push fit connectors jammed up?

Dave