a bit extravagant!-new pcb immediately.
no igition on either hot water draw off or heating?
Do you have ignition?-does a spark initiate?
If the fan sound normal it could be air pressure switch not confirmng such and the boiler will stay running awaiting the air switch operation forever more!
Try pumping air either way to air switch (suction or pressure,bicycle pump or the like-but do not blow into the tube as you'll contaminate the switch if not faulty) and see if any reaction.The air switch needs to confirm fan operation prior to ignition initialising.
chris the gas
February 2009
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