Hi all.

I wonder if anyone can help with this.

I have a Potterton Suprema 60 boiler which seems to fire up even when there is no demand for heating or hot water. My gas bills seem to be higher then they should be given the amount it's used and I think its because of this.

I know some boilers have a 'warm start' type feature to keep heated water more readily available but I don't think this boiler has this (Can't see it in the manual)

Any thoughts on what could be the reason would be appreciated.

Thanks.

Raj, September 2011

does your sysyem have zone valves either 2x2 port valves or one three port if the microswitch is stuck it wil give demand to the boiler when all is off symptons pump always running short cycling of the boiler

deggsy, September 2011

microswitch on zone valve is sticking.

Ian, September 2011

just to say disconnect timer and watch does still come on
or not before changing PCB expensive item timer may be at fault

lal, September 2011

look like PCB is at fault giving signal to gas valve to open
change PCB

lal, September 2011