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I do believe it’s due to the inductive kick of the starting the compressor. My daughter has 2 very large ceiling fans In her screened porch, if both are set to high speed when she turns on the switch it trips the GFCI, if both are on the low setting everything is fine. After starting the fans she can then set the fan speed to high without issues.

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Sep 16, 2023·edited Sep 16, 2023Author

I think this could be due to the inductive back emf spike from the start winding when the relay opens up to take the starting capacitor out of the circuit after 200ms or so during the compressor startup…

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This happened when using heavy duty extension cord into a 20 amp garage plug

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Mine is on GFCI but only because I installed one so I could run an additional outlet so the Wife could sit in her chair and charge her phone. I would have skipped the GFCI but since the wires to the existing outlet were too short to relocate it and is sits right below the PEX line that goes to the ice maker plus the fact that Fleetwood has already demonstrated that every plumbing fitting is subject to leaking...

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What does "in the kitchen" mean in an RV? If you cannot physically touch the refrigerator and the kitchen sink/faucet at the same time, it it in the kitchen?

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Regarding the exemption from GFCI for refrigerators, the proposed 2024 revision to NEC eliminates that. Under the version I have seen, ALL 120/240 VAC receptacles in kitchens must be GFCI.

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I’ll call my contact at CMP-7 to get more intel on that…

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I'd like to know more about this as well. There wasn't really an exemption for the fridge, it's just that the code wording was "all receptacles that serve the counter top" as far as I recall and since the one behind the fridge didn't serve the counter top it wasn't included unless it was within 6 feet of the sink.

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2023 NEC Changes include:

3. Section 210.8(A)(6): GFCI protection requirements in dwelling unit kitchens has been

expanded. The revised language in the 2023 NEC removed the phrase “where the receptacles are installed to serve the countertop surfaces”, thereby expanding the GFCI protection requirement to include any 125-volt through 250-volt receptacle in kitchens — not just on countertop surface. Now the NEC will require GFCI protection for all kitchen receptacles; including the wall space receptacles required by 210.52(A), and the kitchen countertop surfaces covered in 210.52(B).

4. Sections 210.8(A)(7) and 210.8(B)(3): The revised language will require GFCI protection for receptacles located in “areas with sinks and permanent provisions for food preparation,

beverage preparation, or cooking”. These areas are used similarly to a kitchen, but do not

meet the definition. The change could affect an area that includes a “sink” such as a recreation room wet-bar, or a convenience store where beverages or food is prepared. For the purposes of determining the area where receptacle(s) are required to have GFCI protection, the area includes the contiguous countertop or work surface that contains the sink.

5. Section 210.8(D): A list of “specific appliances” was added that will require GFCI protection for the branch-circuit or the “outlet” supplying appliances rated 150V or less to ground and 60A or less. The section clarifies that these appliances must have GFCI protection provided whether they are hardwired, or cord- and plug-connected. The expansion also included 5 new appliances:

o Electric range

o Wall-mounted oven

o Counter-mounted cooking unit

o Clothes dryer

o Microwave oven

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Thanks Bill, this looks like it will include the fridge. I wonder if it is driven by actual injuries and deaths?

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Mike,

As a side note, over the years we have seen a few residential refrigerators in homes on GFCI circuits and I don't recall any complaints of tripping. As you know the GFCI requirement has nothing to do with the fridge, but everything to do with the location. We see many refrigerators and freezers in garages and basements that are required to be on GFCI (all exceptions were removed years ago). We also wire up outdoor kitchens with mini fridges that are required to be GFCI protected, never had a complaint of a trip. The other location is on old 2 wire systems where we GFCI protect entire circuits to allow 3 prong receptacles, have not had any fridges tripping those either.

Of course I have heard and seen on the web stories of tripping, usually on older units. My general thought was that there is a problem with the fridge or the installation if this happens. It will be interesting to see what you turn up.

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The GFCI refrigerator tripping problem was in a new 2022 5th wheel RV with a large residential fridge. But I have much more to study…

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It is my understanding that motors, specifically their windings, which are constructed of many coils of thinly-insulated wire, are inherently leaky. And the leakage is aggravated by the high-current activity during startup.

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Sump pumps are not on GFCI circuits either. And they are in a moist environment! It is because large motors startup current will trip the GFCI.

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The exception for sump pumps (other than 3 phase) in unfinished spaces was removed from the NEC with the 2008 edition. Most sump pump manufacturers require GFCI protection on their units in their installation instructions, which by NEC rules you are required to follow.

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