Recent content by mickma

I want to replace a two port motorised valve, Honeywell V4043, to the central heating circuit. The valve is on the top floor by the hot water cylinder. Do I need to drain the whole system or can I just drain the top floor? Must I latch the valves open during draining and refilling? Finally when...

Thanks Clearhead for your response. There are two Honeywell motorised valves, one for CH and other for HW, but no manual or automatic air vent between the pump and the motorised valves. I think the valves are opening because there is no problem with hot water and now the upstairs radiators have...

I have an open vent central heating system, which I drained and refilled in order to replace two TRV s on ground floor radiators. Prior to replacing the valves, it was not possible turn on the central heating independant of the hot water coming on and when I checked the two port motorised valve...