I have a baxi 105e combi boiler which seems to work when it wants to. sometimes when you turn the hot water on it gets hot sometimes not and the same with the heating. There is nothing on the error lights but no lights when i turn a hot tap on. when it works everything is fine.
Do not under any circumstances follow Scotts advice. In order to gain access to the fan you have to remove the combustion chamber door and and disconnect the fan from the flue outlet. Unless you are a qualified engineer you will be breaking the law as well as rendering the boiler potentially dangerous. Get a CORGI engineer to sort this out - when will you people learn!!!!
Aarovic
December 2008
Try checking the venturi to see if it's partially blocked by scale. It's situated in the fan, the plastic tubes to the air pressure switch are attached to it. If it is, use a blunt object, like a small screwdriver, to remove the scale.
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