In article , hvacrmedic wrote:

Actually it sounds like a wiring issue. Conductors have an inductive/
capacitive link between them. If you have a stray conductor running a
different load that is close to and parallel to the wires feeding the
fan motor, then you'll get a current imbalance through the GFCI.

That doesn't explain why the GFCI trips _only_ when the fan is switched off.

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Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.