Our fridge showed symptoms of evaporator fan motor dying. The bottom of the fridge was cold but the air was not circulating in the freezer and fridge. Then the water dispenser stopped working. I was about to give up but after an overnight shutdown, the water dispenser started working. I realized that the cold bottom of the freezer must have frozen the water lines. I had more confidence that the evaporator fan motor is faulty.
The fridge is side-by-side Fisher & Paykel that came with the house, never again! When I opened inside of the freezer, I realized that there has been a previous repair of the evaporator fan motor. It was one of those hermetically sealed ones with no ground connection. When I opened sealed plastic casing, the circuitry inside was burned with a terrible smell!
The replacement fan motor has three connections including a ground connection tab. Before putting in the new motor, I measured the resistance between the two terminals and then the ground vs two terminals. The ground connection was open as expected. Since the previous motor had no ground connection, I split the green ground wire going to the chassis of the freezer and connected that to the ground of the motor. The fridge is working now in terms of cooling but it has tripped the GFCI twice within the last 16 hours. We had no GFCI issues before. Some current must be leaking to the ground possibly from inductive loading from the fan. Any suggestions? How critical is to ground the fan motor? The fan motor chassis is practically isolated, it's not touching any metal parts. Thanks.
Update: It's been ~30 hours since the fridge last tripped the GFCI! It tripped the GFCI twice before after five and twelve hours after the fix. The fridge was at room temperature after the fix. So maybe there was something related to the fan motor while the fridge was working continually to get to the target temperature. Maybe condensation build up created a path for some charges find their way to the ground connection.
Best Answer
Most of the refer fan motors I have replaced have been shaded pole, the coil on 1 side, these are fairly safe because if the motor freezes up (pun intended) they do not overheat like some motors do. Without a ground if there is a problem the fan may have 120v on its metal parts but if it is isolated I don't see a problem, I have seen shaded pole motors produce enough EMF or kickback that would trip a GFCI in some cases changing brands solved the problem, I am lucky my state allows for fridges to Not have GFCI , so if changing brands did not work I put in a non GFCI outlet.