turn power on everything seems to be working but will not spark to fire up.central heating worked before only changed heat exchanger because no hot water.
The PCB commonly fails often giving one of the following symptoms:
Fuse on PCB blown - boiler does nothing.
Pump runs but fan not running or erratic.
Pump and fan run but gas valve doesn't open (but check air pressure switch).
Pump, fan & gas valve operate but no spark ignition.
Boiler lights but shuts down after a few seconds because it doesn't detect flame (but check electrode leads and condensate trap if conncted).
PCBs are available on Ebay.
Phil T
June 2010
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