could you repost this question, make and model of boiler, how it was functioning before you replaced the pcb and why you thought the pcb was at fault and list how far through the ignition sequence it now goes before it stops, does it lock out and show flashing lights or fault lights or codes?
john
March 2010
You do not mention the boiler make & model - on my Poterton Boiler it will not light until the pilot is good and hot - the pilot will not burn unless the pressure switch senses that the fan is running OK.
Good luck...
Peccavi
March 2010
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