Hi all, I have an issue with our shower's hot water. The shower is operated using two separate taps for cold and hot water. When the hot water tap is turned on, no water at all comes from the shower head - not even a drizzle. However, when the cold water is turned on it flows freely. The hot water tap itself appears to turn freely to both a closed and open position (the turning function doesn't appear seized). Hot water is available from other taps within the house. The hot water service is quite an old system and located in the ceiling.

I removed the tap shroud and took off the brass fitting, initially expecting this to be the spindle to inspect the jumper/valve. However, I then realized this was a brass extender as the remaining plumbing was inset further within the wall cavity behind tiles. After removing the extender, I can see the shaft of the jumper/valve, however cannot remove this as it is enclosed within the spindle. I used some long nose pliers and the jumper/valve can move freely within the spindle and doesn't appear jammed closed etc.

I did this after turning off the mains line and draining the hot water system (there doesn’t appear to be/can’t find an isolator tap from the hot water in the ceiling). A small amount of hot water came out of the outlet when the valve shaft was wriggled/moved around with a pair of pliers; I believe this is water remaining in the piping and indicates that there isn’t a blockage?

I considered an airlock and followed instructions on how to rectify this by removing shower head, placing finger over shower outlet to block flow, turning on hot tap fully then turning on cold tap to flush cold water back into the hot line (where a possible airlock was located). However, I haven't had any luck and the problem still remains.

I'm not a plumber and have limited experience; I've changed a few jumper/valves on a sink in another house and that's about it. Apologies if my terminology isn’t on point. Is anyone able to shed some light on what the issue is here? A few weeks prior the hot water was working fine in the shower.

Happy to provide any further information if it helps.

Cheers
Dan