I have a Vaillant Combi-heater VCW sine-T3W. The central heating runs fine but does not fire up when i put the hot water tap on. If the central heating is running and i put the tap on the water comes out hot, but if the central heating is off and i put the tap on, the boiler does not fire and the water comes out cold. I recently changed the room thermostat but after chatting to a plumber friend he said it should not effect the water.
Have had diverter valve mentioned to me and a wax something or other, any help would be greatly appreciated.
Have had diverter valve mentioned to me and a wax something or other, any help would be greatly appreciated.