These are complicated Eric.Firstly make sure the overheat button hasnt popped out.It just needs pressing in and away you will go.If thats ok is the fan definitely running.Make sure if youve had any snow that the flue outside is clear as this will cause many boilers to fail.If the fan is running it could be the pressure switch which if it isnt making wont send power to the pcb for ignition to take place.Difficult mate,as you need to strip it if its not the simplest of faults.
Tony S, February 2009
