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Home Depot informed me that 2023 Electrical code now requires all duplexes in the kitchen to be GFCI protected. (https://www.homedepot.com/c/ab/nec-2023-code-changes/9ba683603be9fa5395fab901e21904c9) This includes the stand alone Refrigerator circuit and the fixed Microwave circuit. Many posts on this site and via google searches strongly advise against putting the fridge on a GFCI circuit. They make a lot of sense. Do they make fridges that won't trip the GFCI and how do you identify them. Is there a work around for the 2023 code?

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  • This may shed some light on the refrigerator / GFCI issue: diy.stackexchange.com/a/231331/79373
    – MTA
    Feb 9 at 13:32
  • 2020 LG, never been on anything but a GFCI circuit, circuit has never tripped.
    – Ecnerwal
    Feb 9 at 13:46
  • But you are not required to bring your house up to latest local code unless you are having major work done, right? Why not leave the refrig circuit as is, w/o GFCI protection? If necessay, use the GFCI breaker you have rather than a receptacle and have to pull the frig out to reset. Suppose you are gone when a trip happens, do you want others in the household to have to pull the frig out? What is the modern practice for placement of the receptacle for the frig? If it could be located so it could be seen and reset with a rod wouldn't that be better than centered behind? Feb 9 at 23:04
  • Jim, the current situation is a 1960s era house wiring with 12/2 wire on a 20 amp circuit serving all appliances in the kitchen. So this is a major upgrade for convenience and safety. The issue is created by the 2023 code. For example my GE Gas oven recommends against putting the oven power on a GFCI circuit. Now that becomes an issue post 2023 code. The physics of the fridge explained in the answers create a theoretical problem which is coupled by anecdotal reports of problems or no problems with a particular new fridge. MTA's link describes the reality of an aging unit. so Wisdom ?? Feb 10 at 13:42

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I am pretty sure that most refrigerators do NOT normally trip GFCI (ground fault) or AFCI (arc fault) protective devices (combined with receptacle or breaker). There are, however, a couple of concerns that have morphed into "how dare you put the refrigerator on a GFCI or AFCI!"

  • AFCIs can react in strange ways

While there could be very limited current leakage issues actually causing problems with GFCIs, my understanding is that the bigger problem is with AFCIs. While a GFCI is really measuring something extremely simple and straight-forward - does the current on the hot wire match the current on the neutral wire - an AFCI does something far more complex. An AFCI "listens" for indications of arcing. That can be due to loose connections, poor insulation or other things. And problems with motors, even with motors that are operating reasonably well, can produce similar results. Many motors draw a lot of extra power (lights dim, etc.) when starting up. Over time they can have all sorts of issues. The end result is that a perfectly functional refrigerator could be detected as an arc fault when there is not an actual arc fault - a.k.a., a false positive. This would result in power being interrupted and, if not noticed in time, food spoiled.

  • Shared GFCI circuits

A shared GFCI circuit can cause a lot of problems. For example, if someone gets a toaster wet as they are taking out the last slice of toast for breakfast they might trip the GFCI protecting the circuit. That's perfectly fine. But if that same circuit also powers the refrigerator then the refrigerator will lose power and, if not noticed in item, result in spoiled food. So a shared GFCI circuit for a refrigerator is not a good idea. A refrigerator by itself is unlikely (but not guaranteed) to trip the GFCI because of the way it is designed - the parts where a ground fault could occur are well-protected (back or bottom) and not near the parts (the inside of the refrigerator) that get wet.

  • Safety Balance

GFCI is a life safety item. But so is refrigerated and frozen food. Preventing problems with refrigerators is, therefore, something to be balanced against the safety provided by a GFCI. Similarly, fire alarm systems provide an important safety function, and in fact the NEC recognizes that and does NOT require (not sure it is even allowed) putting fire alarm control panels on AFCI-protected circuits. You don't want to have one form of safety cause a problem with another form of safety, and figuring out the hierarchy and priority of these systems is important.

A reasonable solution, accepted by many jurisdictions, is to put the refrigerator on a dedicated circuit with a single receptacle instead of the typical duplex receptacle. That avoids the chance of someone plugging another device into the second receptacle and risking an unprotected ground fault. But as far as I know this is not sanctioned in the NEC.

The next best solution, which does satisfy the NEC, is to put the refrigerator either on a dedicated circuit with GFCI protection or on a branch of another kitchen circuit but with it wired such that the GFCI protection for the refrigerator is provided by a GFCI/receptacle that is fed non-GFCI power and that does not power any other receptacles. That way the only thing the refrigerator will have to fear is the refrigerator itself.

All that being said, appliance companies do NOT like returns and repairs, so I am sure the major companies have been working to minimize the likelihood of a new refrigerator causing a GFCI or (more likely) AFCI protective device trip. Even if that was a common problem 20 years ago, I doubt it is that much of a problem today. However, keeping off of shared GFCI protection is still important (see toaster example above).

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    Thank you @codidact,. The good news is that it is a dedicate;d 20 amp service with 12/2 wire ending at a duplex behind the refrigerator. No one will ever attempt to plug something else in. Perhaps I should return the Square D 20 amp breaker in exchange for their 20 amp GFCI only breaker (QO Qwik-Gard 20 Amp Single-Pole GFCI Circuit Breaker) and that will allow me to meet the 2023 code and just cross my fingers that the old fridge won't care. I refuse to move the fridge just so I can reset the GFCI when needed. Could I use a 15 amp breaker? Feb 9 at 4:23
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    @popham Depends on how you define "readily accessible". But it can certainly be done, depending on the kitchen layout. Obviously doesn't work if it is a refrigerator that has the receptacle behind it and no easy access from either side. On the other hand, if the receptacle is above the counter next to the refrigerator (and isn't critical to the every 4 foot rule) then it could be fine. And I just checked - there are simplex GFCI/receptacle devices readily available at a reasonable price. Feb 9 at 4:31
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    "the only thing the refrigerator will have to fear is the refrigerator itself" is a statement that will live in infamy!
    – FreeMan
    Feb 9 at 13:01
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    @FreeMan And until I posted it, that was a GoogleNope - so you heard it here first! Feb 9 at 15:16
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    I will dutifully give credit the first time I use it. The next time will be "as someone once said", after that, it's "as I've always said"... :D
    – FreeMan
    Feb 9 at 15:18
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The source of the problem

The problem with refrigerators is they are a motor load. Motors are inductors. If you know basic electronics, an inductor is the converse of a capacitor: a capacitor resists changes in voltage and will supply infinite current to sustain voltage; an inductor resists changes in current and will supply infinite voltage to sustain current.

That's exactly what happens when the refrigerator's simple click on/off thermostat says "cold enough; let's shut down the compressor". The compressor spikes voltage until insulation breaks down somewhere and lets it through. You may notice this is a perfect recipe for a ground fault.

I mean, in a perfect world, you suppress that spike either by routing that energy through a resistor around the thermostat or across the motor, sort of like a freewheeling diode on a DC motor. This exhausts the energy stored in the motor's magnetic field. Something like a MOV, whose resistance is infinity up to a breakover voltage (which you choose as well above line voltage), and then resistance drops as voltage increases. But refrigerators may not be built with a solution like this, or it may have depleted (most MOVs have a limited service life; they're used in surge suppressors).

Anyway, it's a recipe for ground faults.

So the NFPA is really trying to hold manufacturers' feet to the fire regarding making their appliances GFCI-tolerant, and pushing the industry faster than it can really go. There are other ways to drive the compressor than a simple switch; a VFD for instance will allow soft starting and stopping of the motor, actively managing the inductive energy and eliminating the inductive kick and related ground fault risks. But once you're electronically controlling the motor, why even bother with the formality of rotating a shaft? It's easier to punch a solenoid, and the compressor would prefer that anyway, since compression is a linear motion after all. And that brings us to the latest linear compressors, and that's going great. Talk about "unintended consequences", thanks a lot there, NFPA!

So the "refrigerator on GFCI" problem is somewhat irreconcilable; and further, this extends to most AFCIs, since most include a weak GFCI called a GFPE (30mA sensitivity instead of 6mA).

Solutions

You're using the word "duplex" when you actually mean receptacle. It would really help to stop doing that. A simplex receptacle has 1 socket (optionally: perhaps a switch, USB, cable TV port, etc.)... a duplex receptacle has two.

Perhaps you are under the impression that all American receptacles MUST be dual-socket? Not at all; 1-socket receptacles exist in a variety of forms, fit the same boxes, and sometimes even use the same cover plates.

One advantage of simplex sockets is that it's more credible to say this is a dedicated circuit to one appliance. It's hard to call a thing a dedicated circuit when you installed two sockets on it. AHJs (inspectors) are often warm to giving variances on dedicated circuits to a specific appliance with a special need - and food safety is a critical safety need. By comparison, GFCI on a grounded refrigerator is pretty trite - it doesn't offer much the grounding doesn't already cover. It's an entirely steel box and you're not likely to drop it in the sink.

The option of last resort is to obtain a UL-listed isolation transformer. Plug the isolation transformer into the GFCI-protected circuit, and the refrigerator into the isolation transformer. The inherent isolation of the transformer will prevent any ground faults at the fridge from pathing any current back to the GFCI. Safety will not be impeded, as the fridge side of the transformer is entirely isolated from AC power voltages.

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