my boiler keeps cutting out i took cover off looked in combustion chamber and noticed the ionisation electrode looks burnt out i also noticed a black mark on the spark electrode lead outside the combustion chamber i just altered the postition of the wire and voila the boiler lit up and kept on running this has happened before could either of these things cause the boiler to cut out the boiler is 12 years old so has nt got the fault indicator lights apart from the single red onr

andy, January 2011

yes the spark is very high voltage so any moisture or crack in the insulation will cause a short this can be detected by the pcb which then won't open the gas valve suggest you either replace parts or at least have them to hand if the electrode wears down too much the boiler won't light no matter what you do

brian, January 2011