In almost every house today, you’ll find a ground fault circuit interrupter, or GFCI. These outlets are typically near water sources (kitchens, bathrooms, laundry rooms, outdoors) and are designed to “trip” or turn off the power at that outlet when it detects a short circuit of some kind, often caused by water but not always.
Electric flow happens when the electrical current travels through what’s called the “hot wire” and it then provides power to whatever’s plugged in. When the device is unplugged, the current travels back through the “neutral wire.” However, in the event that electricity keeps flowing, the GFCI outlet will turn off instantly. This mild inconvenience has prevented many accidents, fires, and possible deaths!
Homes today are required to have GFCIs installed near water sources, but many older homes may not have them. Look around you home to make sure you have these in the right spots. How do you know if it’s a GFCI or not? GFCIs have two small buttons in between the receptacles; one says “reset” and the other says “test.” If you see these, great! If your home doesn’t have these, the right time to install them is now! Furthermore, if you do have GFCIs but one or more of them don’t seem to be working, it may be time to replace them.
You can always hire a professional to do this if you don’t feel comfortable, but it’s not too incredibly difficult to do yourself if you take your time. Here’s how!
Gather your supplies.
The necessary tools include a UL-certified GFCI outlet, a flat-head screwdriver, a Phillips-head screwdriver, and a voltage tester. Optional tools include pliers, a wire stripper, and needle nose pliers.
Turn off power to the outlet.
This can be found at your breaker box. Most circuit breakers should be labeled properly, but to make sure you got the right one, plug in your vacuum or a stereo turning it on so you can hear from your breaker box. Once the vacuum or the radio shuts off, you’ll know you got the right breaker.
Remove the old outlet.
Remove the screw in between the receptacles, and then remove the faceplate. Use your voltage tester, sticking it in the junction box to see if there’s any electricity still flowing. If there are any other live wires, you’ll need to find an additional breaker to switch off.
Remove the junction box.
Remove two small screws that connect the junction box to the outlet, and then remove the outlet using the tabs. You should see more wires now.
Examine the wires.
There should be two black wires connected on one side, and two white wires on the other. There should also be a bare copper wire connected to a green screw. The black wires are known as “hot wires,” which supply the power, while the white wires are the neutral wires and the bare copper wire is the ground wire. Unscrew the terminal screws for all the wires and remove them from the outlet.
Figure out which wires are “line” and which are “load.”
When you’re connecting a GFCI outlet, you must connect a specific black wire to a specific outlet screw. On the back of the GFCI outlet, there are two screws for “line” and two for “load.” One set of black and white wires are the line wires, and the other pair are load wires. Determine which is which by using your voltage tester. This will require turning the power back on to the outlet and setting the voltage tester near each wire. When the voltage tester lights up or makes a noise next to a wire (it will be one of the black wires), mark that wire in some way. (A silver permanent marker will work great!) This is a line wire.
Turn the power off.
Grab the marked black wire – the line wire – and trace it back to where it enters into the junction box. It will be paired with a white wire, and this is the other line wire. The other two wires are the load wires. (It should be noted that sometimes “line” and “load” are spelled out on the box, while other times they’re marked “L” for line and “T” for load.)
Install GFCI outlet.
Remove the nuts from all the wires and connect the black line wire to the brass screw of the “line” side of the GFCI outlet. Curl the wire around the screw itself or stick it into the hole on the back of the outlet and tighten the screw – either way is fine. Repeat this step for the white line wire on the opposite side where the silver screw is. Continue this for the load wires. Connect the copper ground wire to the green screw on the outlet.
Put the wires and outlet back into junction box.
This can be tough but go ahead and shove it back in – the wires won’t get hurt. Put the faceplate back on, too, using the screws from earlier.
Turn the power back on.
Hit the “reset” button on the GFCI outlet, as it will most likely be tripped when the power comes back on.
And that’s it – you’ve just replaced (or installed) a new GFCI outlet in your home!