How to Install a GFCI

Installing a GFCI outlet is a relatively simple task that can be accomplished with few tools and little effort. There are only two wiring configurations that you may have to contend with, depending on your situation, so we will cover them both here. This guide is for those who already have wiring in place and are looking to replace an existing device or installing on a new circuit that has already been installed.

This guide will be based on American Electrical standards and 120 volts. Let's get started!

For this task you will need a voltage tester, a screwdriver, phillips or straight depending on what you have, wire strippers, maybe 3 wire nuts and some black electrical tape. The first thing we always do in any electrical repair is to ensure power is off. You can do this by going to your circuit panel and identifying the circuit you are planning to work on. Turn the breaker to the off position. Stating that as we have, I also understand that not every situation is that simple. If your breaker isn't properly marked, you will either need to turn off the main breaker to ensure safety.

Use your voltage tester to determine that power is off by either inserting the leads into the device you are replacing or by testing the bare ends of the wiring. One lead to the black or "hot" wire and one to the white or "neutral."

Scenario 1: New circuit or existing device. One set of wires in box.

If you have installed a new circuit, and your wiring is stubbed into the box, this guide will walk you through the simple steps of installation.

1. If an existing device is present, remove it and make sure you have 6-8 inches of wire sticking out from the face of the box if possible. If an existing device was present your wiring could be shorter. If you have more than one black, white and green/bare attached to existing device, go to scenario 2.

2. The black wire is your "hot", the white your "neutral" and the green or bare copper wire is your "ground." It is very important to have these properly identified. (If you do not have this wiring configuration, or if your ground is missing, you may need to seek the help of a professional electrician to assist you. A missing ground wire can cause this device to function improperly.)

3. Taking your GFCI device in your hand, turn it over in order to view the back of the device. There are several important markings on the back of this device.

• You should see on one side it says "black", the screws on this side should be brass and this is where your black or "hot" wire goes.
• On the opposite side it should say "white" and the screws on this side should be silver. This is where your white or "neutral" wire goes.
• On one end you should see a green screw. This is for your green/bare wire or "ground."
• The top section of screws should be labeled "Line." For this scenario, this should be the only set of screws on the device that you will need.
• You should also see a strip of yellow tape covering the bottom two screws. By this the device will be labeled "Load." You will only need to remove this if you have other outlets you are protecting. That will be covered in scenario 2.

4. To begin installation, determine the type of screw driver you need. All newer devices either have phillips or a square head screw terminal.

5. The newer GFCI devices are designed for ease of installation by allowing you to wire them from the "back." As you can see in the image, there are two holes on the back of the device in line with the screw terminals. Using the strip guide on the back of the device, strip your wiring to the appropriate length. Insert the black behind the brass screw and tighten the screw on the side. This may seem odd, but the screw is pulling in a plate to secure the wire. NOTE: You must tighten this screw in order to secure the wire. It is not like the devices of old that used a spring to hold the wire.

6. Repeat step 5 with the white wire on the silver screw.

7. For the ground wire, you must bend a hook on the wire and place it under the green screw. Tighten screw until snug.

8. Now, this step is my personal preference and is not a requirement. I always take black electrical take and wrap it around the side of the device covering the black and silver screws. This enables me to grab the sides of the device without fear of electrical shock. Again, personal preference and not a requirement, but I highly recommend it.

Congratulations you have wired your device! Now it's time to install it into the box.

1. Pull the device away from the box so that the wires are straight out. Towards the back of the box bend the wire up and then towards the device bend them slightly down almost until it looks like a roller coaster. This will allow the wiring to "fold" into the box.

2. Begin pushing the device into the box, being careful that all wiring stays behind the device.

3. Important note: Do not force or shove. The wiring will find a place to rest in the box, it may just take some patience.

4. As you are pushing the device into the box, the box screws will need to be started. Evenly tighten the two screws into the box until the device is firmly in place.

5. Install cover and then restore power.

6. Press the "Reset" button on the device. Then press the "Test" button. If the wiring is proper, the device should click. Press "Reset" once again and you are ready to use your new device. Congrats!

Scenario 2. Protecting outlets "Down line."

The only difference between this Scenario and the first is if you have outlets "down line" from the GFCI you are installing. If so, it is very important to make sure you know which are your "feed" wires in the box and which are the "load" wires. Again, if you aren't able to determine this you need to seek the help of an electrical professional.

Repeating the above steps, you only need to add two things.

1. If you have two ground wires, do not place them both under the green screw. Instead "pig tail" or tie two of them together with a wire nut leaving only one wire to go under the screw.

2. The wiring that goes "down line" has to remain separate from the feed in order for the device to work properly. This is where you remove the yellow tape from the back of the device. The wiring that goes to the devices down line is to be installed on these screws.

3. When you have finished you should have both black wires on one side of the device and both white wires on the other.

Using the steps from scenario 1 you should now have a successful installation. Well done!