Fault is probably nothing to do with the fan but it might be an issue with the fan HEATING element going down to earth or top or bottom elements.you need a megga to test it so resistance with a multimeter may not show issue to earth unless it totally collapses.the megga puts 500v to earth and gives reading.from this you can tell if element insulation has failed.
CK
October 2013
OK replaced the fan sometime ago. With the tester what would I be looking for in terms of resistance etc
charlie
October 2013
element issue.either fan element or grill.need test meter connecting at time of tripping to decide which
CK
October 2013
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