possibly???. if you try the prev mentioned and no signs of blockage then think harder :-). you can generally check aps as open line or closed circuit only, using multi meter. meter cant really tell you if its struggling rather than failing. eg baxi would ind blocked flue/fan led but chances are it would be aps.
iain
March 2008
could be a flue blockage?
T
March 2008
think if it was me, i would try taking aps tubes off and make sure they clear and not cracked or split. take fan out and make sure venturi is clear and aps tube connection points. it involves no parts and only small amount of time. good starting point i would say.
iain
March 2008
because it works with cover off suggests that aps could be working but supply air to it being restricted ie blocked venturi in fan or aps tube. really hard to say without being there.
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