IMy Potterton Kingfisher II RS80 was working fine till this morning, now when try to activate either hot water of heating boiler does not fire up at all, pilot light is lit but nothing else is firing up, anyone got any ideas?

Ralph H, January 2010

If there is nothing at all, it could be something as simple as the thermocouple.
If the thermocouple isn't conducting heat to the gas valve, then the gas valve won't open and allow the burner to kick in.
They're anything up to £15 at any Parts Center/Plumb Center,...far cheaper than a gas valve which could cost up to £200.
Good luck

Northern Knight, February 2010

Need to know if power going into boiler if not external control fault
If power at boiler suspect gas valve

a, January 2010