Please can anyone help, the pump runs all the time and the boiler fires up every so often even when the system is programmed off. The only way to switch it off is to isolate the whole system.
If the programmer is set to off there will be no supply at the Zone valves. How long has the system been in and has it worked fine before? 552 has a permanent live so if you do not know what you are doing call a heating Engineer.
Brian, September 2006
yep hes right check the micro switches inside the valve if your competant to do so .if not get an engineer.
gas boiler service nottingham, September 2006
HI, i'm guessing here but I suspect you have an 'S' plan system with two or more zone valves? one of the valves will be faulty. If you are good with electrics check for 240v on the orange wires from the valves to see which one it is. Be carefull as you will have to disconnect and seperate them to check the voltage. If unsure get a qualified engineer to do it!
