My boiler will not stay on. The pilot light lights the gas but then turns it off, then on again, then off again. It wll light for about 3 seconds, then off, on off etc. My local corgi man has changed the Air Pressure switch, PCB board, and finally the gas valve but the problem still persists. Can anyone who has any clue to what the problem is please answer? thanks
dale

Dale Meyer, March 2007

Try the plug in mercury vapor pilot sensor. White Rodgers 3094. Good luck finding it,it may have been discontinued.

John the King, November 2007

Did you manage to fix your boiler? if so what was causing the problem. I have same boiler with same problem, so far replaced gas valve. your solution might also work for me too. thanks

faz, April 2007

It is probably the ignition lead and or electrode ,These boilers use flame rectification.when your ignition lights the heat creates a signal via the ignition electode and lead to the circuit board to tell the gas valve to stay open as a flame is present if there is bad contact or damage not always visible to the lead or electrode continuity is lost and the boiler closes down. 99 percent certain that will fix the problem

steve@thermagasplc,com, March 2007

the fan working ok

hi-spec plumbing, March 2007