My house just went through a flood and there was 7 feet of muddy water on the first floor, so all the AC outlets were underwater. After the water receded, all the unprotected outlets continued to work just fine. But 4 out of 5 GFCI outlets no longer work and cannot be reset. Can GFCI outlets be taken apart and cleaned/fixed or is there something inside that fails permanently?

Also, all the GFCI outlets are at the ends of their lines. In other words, there is only one wire connected to each LINE terminal and no wires connected to the LOAD terminals. So they only seem to be protecting themselves. But if they failed once they got wet and all the non-GFCI outlets survived, can I just replace them with non-GFCI outlets?

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    You should probably replace all the outlets that were underwater, whether or not they are working now. – chepner Apr 2 at 19:09
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    All this flood remediation work should be covered by insurance, no? Cost shouldn't be a consideration here. – Criggie Apr 2 at 19:31
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    Wait a minute, landlady? Why are you repairing/replacing anything? – Nuclear Wang Apr 2 at 19:45
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    @manassehkatz Having been through an 8 year insurance nightmare due to quake damage, I am convinced insurance is the single most unethical industry that is still "legal" If OP did the replacement and 20 years away there was an electrical fire, an insurer may refuse to cover that event as well. – Criggie Apr 3 at 0:06
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    @Patrick Not sure how the laws apply in your location, but here in NZ one is barred from doing electrical work for reward (ie pay) unless you're certified and qualified. The only things a non-certified person can do is replace lamps and fuses. Replacing a face plate could only be done if you are the home owner, under a DIY exemption. Since you're working on this for reduced rent, it could be taken as working for reward. Be careful. – Criggie Apr 3 at 0:09

Not worth the risk

GFCI (whether in receptacles or breakers) are sensitive, life safety electronic items. As such, you don't want to mess with them. In fact, the whole purpose of the TEST/RESET buttons is because they can fail, even without obvious problems such as a flood. Newer models even test automatically.

Is it possible that there is simply still water inside the GFCIs so that disassemble, dry, reassemble will work? Yes. Is it a good idea to try that? ABSOLUTELY NOT!

New basic GFCI receptacles are in the $15 - $20 range (varies depending on brand, 15A vs. 20A and other features). Not as cheap as plain receptacles, but not that big in the grand scheme of things.

Presumably the GFCI receptacles were installed because the particular locations - basement, bathroom, laundry room, etc. required them. Assuming that is the case, replacement with plain receptacles would be a code violation. In most places you are not required to upgrade to GFCI unless you are making changes, but downgrading doesn't make sense and is likely a code violation.

Panel Alternative

An alternative is to install GFCI breakers in the main panel. This has the disadvantage that your panel may not have room for GFCI, or if you have a very old panel or fuses instead of breakers then that is not even an option. These breakers also typically cost more than "ordinary breaker" + "GFCI receptacle" so this change would be for practical reasons (e.g., protect outside circuits where a GFCI receptacle would be subject to severe weather) or as part of a panel upgrade. If you are looking at simple cost, replacing the GFCI receptacles where they are currently located will almost certainly be the way to go.

Check Out Everything Else

As Harper noted, there are plenty of other concerns as well. This is one situation where DIY may really not be enough. You could have hidden damage that can come back to burn you (literally) when you least expect it. Professional evaluation of the entire electrical system that was underwater is worthwhile.

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    @Patrick To be clear, even if it were 300 replacing would be the way to go. These devices aren't here for fun. Do it right. (And if you value your time at all, there's about a 0% chance doing anything but replacing broken receptacles would be cheaper.) – GManNickG Apr 2 at 20:33
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    @Joshua Computers - or almost any properly functioning equipment - should not care whether it is on a GFCI or now. I'm sitting in my basement right now with my computer on a GFCI receptacle. Never a problem. There might be issues in some circumstances with equipment causing problems for AFCI, but even then computers should not be the problem. – manassehkatz Apr 2 at 21:04
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    @Joshua I've never had a problem. Most of my customers' computers are not on GFCI, but I haven't seen this at all. Are these servers, desktop computers or specialized equipment? What kind of power supplies? – manassehkatz Apr 2 at 21:41
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    @Joshua Well, I've never seen a problem myself. I can see issues with powerline networking not getting past GFCI of AFCI. I can see why AFCI would be extra sensitive to a lot of things. But I don't quite get why GFCI would have a problem as long as the computer (or router or whatever) power supply is functioning properly. – manassehkatz Apr 2 at 21:57
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    @Joshua and others -- I've put a question on this up on EE.SE, hopefully, the answers there shed more light on this problem. – ThreePhaseEel Apr 3 at 2:54

It's worse than that. The cables are done too.

Most houses are wired with Romex (NM) cable. That's not rated for getting wet. It has paper packing inside the sheath that just wicks water like crazy.

If the people who built the house were flood savvy, they built with UF cable, which is wet-rated and notably does not have that paper packing. It will be fine. Or they built with conduit and use THWN or THWN-2 individual wires. Those are also wet-rated and work fine even if the conduit is full of water, which is the normal expectation outdoors.

All the switches and outlets are done

Flood damage destroys everything, becuase it's not just water, it's a lot of crud too. Flood cars are finished. Some of that crud is electrically conductive, and it has gunked up each of the receptacles with it. Also, the crud is corrosive, so anything in that receptacle that could corrode, is right now.

For all those reasons (electronics are extra sensitive to corrosion), the GFCIs are all finished and must be replaced.

The service panel is also done

Service panels, even outdoor rated ones, are not rated to go for a swim. The crud is also inside the breakers laying conductive tracks and doing corrosion damage. These breakers will no longer be reliable. It might be possible to pull the buses out of the service panel and clean them, you'd have to see.

If you look at news footage of Houston's recent flood, you see lots of 2-storey apartments, 1st floors flooded out, and 2nd floors with the lights on and the A/C running. Flood-savvy builders take their power from overhead lines not underground, and put the service panel on the 2nd floor. They put 1st floor circuits on GFCI breakers so they don't electrify the water and drown people. A GFCI breaker protects the entire circuit and makes GFCI receptacles unnecessary.

All GFCI devices can protect downline loads if wired correctly. You are correct that a GFCI receptacle on the end of a circuit is a bit of a waste.

(Usually) you can't work on rental properties

Most areas have a law that only licensed electricians can do work on rental properties. That is to prevent landlords from doing shoddy work on the cheap and killing their tenants.

Check with your local authority (the department in City Hall you go to pull permits). They will tell you what a handyman can and cannot do with electrical in rental units. If they allow you to do anything at all, it would be limited to changing receptacles, switches or lights. GFCI receptacle changes could be included in that.

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    The silver lining is that since the walls need to be torn apart to eradicate mold, getting access to the ruined electrical cables will not be difficult. – Ben Voigt Apr 3 at 0:44
  1. It's not practically feasible to clean and repair a GFCI outlet. They're fairly elaborate and sensitive gizmos, and they're not designed to be disassembled. Could you pull it off? Probably. Would I want to? Nope. Would it void the UL listing? Yup.

  2. Whether GFCI outlets are needed at the end of a circuit depends almost entirely on where they're located. The fact that they're the last in a string of outlets is inconsequential. Are they in locations normally exposed to water, such as kitchens and bathrooms? If so, they need to stay.


Can GFCI outlets be taken apart and cleaned/fixed or is there something inside that fails permanently?

A GFCI protects you by using a circuit board to watch the current flowing out of the hot and coming back into the neutral. If it reaches around 5mA imbalance, the breaker trips. You said yours were submerged in a flood. Just like your cell phone or computer, the flood ruined the circuitry inside. You cannot repair it yourself (assuming anyone can repair it).

Replacing them is not terribly expensive, and the newer ones have a self-test mechanism.


As a homeowner, an electrical engineer, and a fair tinkerer, I would not attempt to repair a GFCI unless I was desperate.

However, if I absolutely had to, what I would try is first rinsing with plain water and a few drops of dish detergent, then rinsing in distilled water with a few drops of dishwasher "rinse agent" added, then rinsing in plain rubbing alcohol. Do all these rinses thoroughly, so that the fluid is swished through the fixture. Then shake dry the best you can and put in a 100 degree oven (no warmer!) for an hour or two. If that doesn't fix it, toss it in the trash!

It would be interesting to take one of the things apart to see how it's made, but I'm guessing it would be impossible to get back together again. To be successful you'd have to sacrifice one or two units to help you design assembly jigs of some sort, and you'd probably have to find some replacement rivets from somewhere.

With regard to the wiring, it's kinda iffy. You especially want to make sure the GFCIs are replaced, and that, when reinstalled, they are properly grounded. (Check the continuity of the ground wire!) Any cabling that looks suspicious (especially scummy or "burned looking", eg) should be replaced. And any regular outlets in, eg, nursery areas, where gerfingerpokin is apt to be going on should be replaced.

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    You are right about having much difficulty putting them back together, as most safety devices are constructed in a tamper-proof way, having no serviceable parts inside. If they look like they have been messed with, they should be tossed out as nobody with any authority will approve them. "Insurance void if opened". – sleblanc Apr 3 at 4:05

To separately answer the "end of the line" question re GFCIs, no, placing them at the end of a sequence of daisy-chained outlets is not in any way required by code, and it provides no protection to the rest of the circuit.

One wonders if the previous occupant replaced standard outlets in these locations with the GFCIs, under the mistaken impression that the would protect the entire chain.

Now might be a good time to reassess the situation (especially given the possible unseen water damage to the wiring) and install daisy-chained GFCIs as the first outlet of the circuits, or at least those circuits that are closest to humans.

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