Replacing a GFCI Outlet





Introduction: Replacing a GFCI Outlet

GFCI , or Ground Fault Circuit Interrupter, outlets are required by code on outdoor outlets, or any outlet near a source of water. The one exception is that outlets intended for motor-driven appliances, like washers and driers, don't need a GFCI, as GFCIs don't work with inductive loads.

They work well when new, but eventually fail and need to be replaced. Here's how to replace a GFCI outlet- or any outlet, really- or replace a standard outlet with a GFCI outlet.

Step 1: What You'll Need

It doesn't take many tools to do this job- here's what you'll need:

- New GFCI outlet

- Insulated screwdriver

- Outlet tester

- Non-contact tester

- Electrician's pliers

All are inexpensive. The non-contact tester is used to see if a circuit is "hot"- that is, if there's voltage on it. The Outlet tester is used to make sure you've wired everything properly.

Step 2: Turn Off the Power!

Go to your electrical panel and turn off the circuit for your outlet. Not sure which one it is? Don't worry, we'll check as we go along.

Step 3: Remove the Faceplate

Unscrew the two short screws that hold the faceplate to the outlet, and put the plate and screws aside. If you put the screws in the upside down faceplate, there's less chance you'll lose them!

Step 4: Remove the Outlet

Remove the two long screws that hold the outlet to the box, and carefully withdraw it...

Step 5: Double Check the Power!

Using the non-contact tester, check the black wire... oops, looks like this one's still hot. Don't wait until you've pulled the outlet all the way out of the box- keep checking from the moment you remove the faceplate!

Notice that all the exposed connectors on this outlet are covered with a wrap of electrical tape- that's a good precaution whenever you install an outlet or switch. It helps prevent accidental shocks the next time someone services the box.

Step 6: Prepare the New Outlet

Note that the old outlet had the "ears" on the mounting tabs broken off to fit in this location. They're scored to make it easy to do this.

Here, I've grabbed the tab on the new outlet with my pliers, right next to the scored line. I'll bend each tab back and forth a few times and it'll snap right off.

Step 7: Wiring the New Outlet

Your GFI outlet has five different connectors, and it's important to know which is used for what.

The ground screw is connected to the ground wires coming and going to the box.

There are two sets of connectors for hot (black) and neutral (white) wires. One set, labeled LINE, is used for power coming in to the box, and the other, labeled LOAD, for outlets that will be "downstream" of the GFCI, and be protected by it. Make sure you know which is which- the old outlet will be labeled, as will the new.

If you can't see the markings on the old outlet, turn the power on briefly, and use your non-contact tester to find the hot wire- that's the one bringing power into the box. You'll connect that wire, and its white companion, to the LINE connectors. (And then turn the power off again.)

This GFCI outlet has both push-in and screw terminal connectors; some old timers (and some new-timers) will only use the screw terminals, but actually, the push-in connectors are more reliable, according to the GFCI makers.

Make sure the wires are stripped to the right length- there's a gauge right on the side of the outlet.

I've pushed the wires into the holes, tightened the screws, and put a couple wraps of tape around the outlet. Now it's time to reinstall.

Step 8: Replace the Outlet

Carefully push the outlet into the box, and replace the two screws that hold it in. Don't make them too tight- only screw them in far enough so that the outlet is almost flush with the wall.

Step 9: Replace the Coverplate and Test

Reattach the cover plate, and turn the power back on.

Now plug in your circuit tester. You should see the two amber lights light up, but not the red light.

Push the test button. You should hear a snap, and all the lights will go out.

Push the reset button, and the amber lights should go back on again. If they did, congratulations. You're done.



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    The outlet is not coming out, it feels as though something is holding it in place. I need to replace it because when I had to reset the gfi the actual reset button flew out of The outlet & landed several feet away. I tried to place it back in position however it didn't go as planned & the reset button is apparently in the wrong position & cannot be removed. I tried the test button but nothing will dislodge the reset button. ARGH! Any suggestions on dislodging the reset button & getting it set properly?


    Is it normal for the plug to be hard to get in and out when replacing a new GFI outlet?


    Very helpful, learned a couple things from this and the comments. thanks

    Good instructable. You might want to start adding Arc Fault Circuit Interruptor ( AFCI ) breakers to your breaker box. That type of wiring has a tendency to crack and cause fires with age. The rubber dries out and is degraded with ozone and other atmospheric conditions. The natural expanding and contracting of a house adds mechanical stresses. After the insulator is gone a fire is almost sure to happen. I have run into this many times doing favors for neighbors and friends. The breakers only protect you if that happens. The ultimate protection is new wiring. But it will help keep you and your family safe until you can do the last step. The 2005 NEC requires them for all bedroom and lighting circuits. As more building codes are updated the cost does go down. But looking at those pictures I would say get them now. Start with the circuits that have the that wiring in place then finish with the newer circuitry. Yes AFCI's and GFCI's coexist nicely as long as the hot and neutral are truly separated.

    "The one exception is that outlets intended for motor-driven appliances, like washers and driers, don't need a GFCI, as GFCIs don't work with inductive loads."

    But the new washer I just purchased has a three-pronged electrical cord...I am using an adapter right now, and the warnings on the washer say that's wrong.  SO, I'm thinking I *still* need to install a GFCI to plug the washing machine into...but will the machine work with it?  HELP! :^)  And Thank You!!

    1 reply

    I think you're talking about different things. I assume you mean you have a 4-prong plug and got an appliance with a 3-prong cord, and you're using using some sort of 3-prong to 4-prong adapter.

    You can't change the plug; it's required to be a 4-wire. However, since you say it's a new washer, it's almost certainly possible to change the cord (you should have asked for 4-prong when you ordered it :-). It's pretty simple to do, but not knowing which make/model washer you have, I can't offer details. You'll want to go back to where you bought the washer, or to a well-stocked hardware store, and ask for a 4-wire cord kit for your washer.

    here we dont have a gfci but a breaker using the same principle as a gfci but no ground(380V 3P+N)

    2 replies

    I found the 220V 1P+N equivalent on our panel

    wtf they are like a hundred bucks here

    I am wondering if I can replace an old "razor only" receptacle with a new GFCI?? Or will I have to change the wiring??

    2 replies

    The NEC (National Electircal Code) says you can put a GFCI outlet on any two or three wire circuit, But if you add a GFCI for a two-wire circuit without a ground, you must mark the receptacles with the words “GFCI Protected” and “No Equipment Ground” A groundless GFCI still provides ground fault protection, and is sfaer than a three-wire circuit that's not protected by a GFCI. As MD_WIllington noted, a GFCI works by detecting a differerence between the amount of current being carrried on the black and white wires- the assumption being that if there's a difference, there's current going where it should be going- like through you. You only need two wires to detect that.

    Thanks for clearing that up. It is appreciated.

    "The one exception is that outlets intended for motor-driven appliances, like washers and driers, don't need a GFCI, as GFCIs don't work with inductive loads." FYI, for those wondering why they will not work properly with inductive loads, inductive loads draw large amounts of current at startup, therefore every time the inductive load starts, the GFCI will interrupt the inrush current and trip off power. It is actually a small differential current device inside the unit that detects the difference between current in and current out. If your house was built before GFCIs were required, your local building codes may not necessarily require them, as this would be an existing non-compliance and they do not work if there is no ground wire present, or if there is a ground wire present due to renovation yet the wire is not attached to anything, i.e. the ground is floating.

    got some fancy tools, but no auto wire stripper?

    3 replies

    I never use those fancy stripper tools either. A regular pair of dikes (Diagonal Cutters) and a skillfully placed finger acting as a gap control makes a most effective stripper. Besides, you can't strip that old cloth-covered wire with strippers. They were insulated with real rubber back then and now it would only break off to expose the wire. This is why, I expect, the electrical tape is being used to cover already exposed wire within the box.


    THi isn't the old varnished cabric wire, or plain cloth, but cloth over rubber. You can push back the cloth, but you need to strip the rubber coating. I don't use dikes in electrical work- too much chance of nicking the wire, which can lead to a break, and then arcing, and fire. I use cheap electrician's plier that can strip all the standard sized as well as Romex jackets.


    The point I wanted to make is that you can do it with a very few cheap tools. I've never seen an electrician use auto strippers; they're more of a technician's tool.

    Great instructable! Wow! That looks like some old house wiring! I haven't seen cloth covering on the insulation since I left Minnisota! How old is this building? In one of my old appartments the GFCI was tied to two bathrooms where the circuit-braker unit (like above) is in only one bath. The other bath's normal outlet was tied to the GFCI in the first bath. While curious about it, I never pulled the outlets to see how they were tied together. It would help to have a photo indicating the contacts on the outlet and how they're identified.

    1 reply

    Yeah, after I had everything together I thought I should have more on the details of wiring. If I have some more outlets in the basement I'll do that. This instructable was opportunistic- I had to replace the GCFI, so I shot a lot of pics. The house was started in 1936 and finished in 1937. The wiring has been updated a few times, most recently in 1999, when I added a floor and redid the kitchen. The breaker box pictured was added then, as was the tile- my very first tile job.

    Great Instructable! I'm sure this will help many people! :-)