Warmflow 70/90 Boiler

[trrence]

Hi

I have a problem that with the CH turned off but the DHW resevoir thermostat turned on at the front of the boiler it has suddenly started to heat all the radiators in the house and the boiler is obviously constantly firing up to keep the tank hot. It has been losing pressure for a while but I think that is due to a faulty air bleed valve. Can anyone advise please?

 

[trrence]

I have now managed to trace the fault to the fact that the radiators are getting their hot water from the CH return into the boiler so they are feeding in reverse. However when the heating is switched of and the CH turned on it works the correct way around. Can anyone help please as it is driving me nuts?

 

[JimH]

I have now managed to trace the fault to the fact that the radiators are getting their hot water from the CH return into the boiler so they are feeding in reverse. However when the heating is switched of and the CH turned on it works the correct way around. Can anyone help please as it is driving me nuts?

Sounds like the solenoid for your CH is stuck open - allowing the hot water from the pump to pass??

 

[trrence]

Jim, thanks for responding.

I did find the fault in the end, it turned out that this boiler has 2 non-return valves fitted in the dual pump housing. The CH valve was stuck open after a summer of no use so it was just a case of flushing the system through and stripping the valves out and replacing. Job done for under a tenner which was a relief.