I have a vented system with a bog standard Grant external boiler. Basic Drayton timer and room stat. Radiators all come on even if only HW is selected. The boiler cuts out when hot water reaches temp. I've proved this by turning the stat up and boiler fires up.
The Grant approved engineer changed the top of the 3 way valve and the indicator moves correctly but could the actual valve be at fault? If I just press CH on the timer, there is no demand. There is no air in the system. Any advice please?
The Grant approved engineer changed the top of the 3 way valve and the indicator moves correctly but could the actual valve be at fault? If I just press CH on the timer, there is no demand. There is no air in the system. Any advice please?