Recent content by Mafopp5

Thanks for all the responses. I think it may be the programmer and will change that next week. I'll also check the motorised valves in case their microswitches have stuck. great help thanks.

After years of no problems, my boiler now operates only on its internal thermostat, even when the timer is off. I thought it might be the frost stat, but this checks out okay. To shut it down at night I have to turn it off at the mains. The fan seems to be permanently on. It is a Potterton...