if you dont know how to check each component operation during the ignition sequence then call an engineer, it could be a slow fan, damaged tubes to the air pressure switch, the actual air pressure switch, the ignition lead, the spark electrode or pcb, or case seal to name only some of the possibilities. if it is the pcb or fan then british gas 192 pound fixed repair fee is good value. but if its a tube or lead its a bit much, you will pay the same either way
john
February 2010
A heating engineer will soon sort you out...
When the boiler is asked to fire up the fan runs and when the pressure switch detects it's OK the pilot is lit and when the pilot flame is properly sensed the main gas valve is opened - The boiler's PCB controls the sequence.
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