You have checked the obvious: (that the pump is running when the boiler cuts in) All the radiator valves are turned on and the motorised valve (if fitted) is in the heating open position.
Geoff
April 2005
Is your room stat set to the correct temperature and calling for heat? If not, it will switch off as you describe
Alan
January 2005
I can answer this question...
how can i fix my potterton kingfisher 2 gas boiler?
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