Help ! Glowworm Complheat 55 No hot water

[gordon353]

Hello, I have a glowworm Complheat 55, central heating is fine, but when flicking the controls to just hot water the boiler does not fire up....only when flicking to heating or heating and hot water does the boiler fire, but still no hot water coming out of the taps???? Please help!!!

The light foe hot water on the controls does not light either, but the heating does?

 

[petit_pablo]

Theres a flow switch with a rubber diaphram inside that has most probably perished.

I cant recall where in the boiler it is but it should be visable behind white case within all the other pipes