I believe this model is now obsolete and i seem to recall a memo which circulated some 2/3 years ago that major repairs involving opening the combustion chamber renders the appliance illegal, or at least puts its safety in question.This was apparently to do with not being able to replace the casing seals or some safety issue with the products of combustion(carbon monoxide).
Never had the need to check this info because i have'nt seen one in ten years that was still working.
Chances are, it's the fan that is blowing the fuse, and you would need someone registered to open it up to find the true fault.
It may be easier to ring potterton and ask if they still do spares and check the validity of repairing it in respect of casing seals etc.
T.h.s
July 2007
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