Refrigerator Tripping GFCI Suddenly

Question

I have an issue with my LG fridge. The fridge is 2 years old and has been working fine until this morning. When I opened the doors the lights when out. I (after some time) figured out that it had tripped the GFCI in our kitchen (which we didn't even know the two outlets were connected. I have been doing some testing and it ONLY trips the GFCI when both doors are opening simultaneously. I can not get it to trip when just one or the other door is open. BUT if I open both doors at the exact same time the GFCI trip. I ran the refrigerator to another GFCI outlet via an extension cord and it tripped that one as well. My gut it telling me there is a ground fault in the door switch, but I can't understand why it wouldn't trip when I opened that particular door. I thought the control unit that lights up, but it also lights up when only one door is open. I thought perhaps the actual lights, but those come on also when only one door is open. Does anyone have any suggestions, or other tests I could perform to narrow it down.

The model is a LFCS22520S

Thanks so much in advance!

Answer 1

The fridge shouldn't be on GFCI anyway. Imagine if it had tripped over the night, you woke up to make coffee, the coffeemaker didn't work and you found the GFCI tripped, and you reset it naturally. Would you register what it means when the fridge also starts up? Or would the fridge re-cool by the time you go to get food out of it, and you're none the wiser that it was ever off? Meanwhile food has spoiled.

If the fridge is downline of a GFCI, then stop using the LOAD lines on that GFCI, and fit additional GFCI receps at any other place GFCI is needed again without use of LOAD.

What to do about the refrigerator, though?

Henny Youngman had a joke, "I told the doctor 'it hurts when I do that'. The doctor said 'Well, don't do that!'"

There's a reason we advise not to put fridges on GFCI.

Fridges do that. New fridges do that. Therefore, a fridge tripping a GFCI is a nothingburger in my book.

"Oh, noes, but it's unsfae!" OK stop. Why do we have GFCIs in the first place? Because people get shocked by ungrounded (not a fridge) appliances whose electrical bits are exposed (not in the bottom back of a 300 pound machine shoved into an alcove), which get wet (not likely) and who often drop the appliance into the sink.

Absolutely none of this fits a refrigerator. They are simply not the use-case for which GFCI is intended (or able) to help. Putting one on GFCI simply makes no sense.

And indeed, AHJs see it that way - they will often exempt "Fridge/freezer only" outlets from the rule requiring GFCI for all basement and garage outlets.

Keep in mind a fridge is a safety system. You keep perishable food in it.

Chasing it anyway

If you feel strongly about running down the problem, I would start by slicing up an extension cord and separating the ground wire a good distance from the hot+neutral (bind those together). Now you can put a clamp ammeter around the ground (or hot+neutral, as normal current will cancel itself out) and look for the leakage current. I readily acknowledge that a refrigerator light is an unusual source for a ground fault, and may be worth investigating.

Normally fridge ground faults happen when the compressor motor is shut off; that causes an inductive "kick" that will rise in voltage until it is shunted to neutral or ground. Refrigerators may have devices such as a VBO to deal with that, which then fail over time.

Answer 2

It may be related to the cleaning method. Nowadays many users prefer cleaning sprays, which would settle and accumulate on even the interior surfaces through tiny openings, where hot wires are present. These residuals have conductive components (ions) which lower the surface resistance. Depending on which parts are set on high voltage, the opening of one or two doors could start a leakage current that will trip the GFCI. Spraying those internal parts with isopropanol (alcohol) can help to remove those conductive residuals. Of course, the fridge must be disconnected from the power and only reconnected when all alcohol has disappeared.