Over time, electrical outlet receptacles go bad. In older receptacles, the hard plastic around the slots can age and crack. Newer receptacles are made from more resilient vinyl plastic, but over time the metal contacts inside the receptacle can become worn and fail to hold cord plugs securely. Sooner or later, every homeowner is faced with an outlet receptacle that needs to be replaced.
Work on an electrical wiring system should always be approached with caution because there is always the danger of shock, but replacing a receptacle is a relatively easy job that most homeowners can do themselves with a little knowledge and the rights tools and instructions.
Hiring an electrician to do this work can be quite pricey, especially for a job that only takes about 15 minutes. Replacing existing receptacles, switches, and fixtures can be done by a homeowner without a permit.
Before You Start
This project shows how to replace a basic 120-volt receptacle. Ground-fault circuit interrupter (GFCI) receptacles require a slightly different procedure, not covered here. Nor does this project cover 240/250-volt outlets, such as are used for electric stoves, large window air conditioners, clothes dryers, and other large appliances.
Be aware that standard120-volt receptacles typically come in two amperage ratings: 15-amp and 20-amp. They look quite similar, but on the 20-amp receptacle, you will notice that one of the vertical slots will have a "T" shape. This is designed so that the special plugs on appliances that draw 20-amps of power can be plugged into them.
Standard appliances can also be plugged into these outlets. Normally, you should be able to simply look at the old receptacle and buy a new one that looks exactly like the old one. But it is a good idea to check to make sure the receptacle does not exceed the circuit rating. Make sure that the amperage rating of the receptacle matches that of the circuit.
While there is no danger to installing a 15-amp receptacle on a 20-amp circuit, a 20-amp receptacle should never be installed on a 15-amp circuit.
Before you start any electrical work, it is crucial that you understand how to shut off the power and test for current. Study up on this skill before you attempt any repair work, and if you are uncertain about your abilities, hire an electrician to do the work.
Tools and Materials You Will Need
To replace an outlet receptacle, you will need:
- Replacement receptacle to match amperage rating of the circuit
- Non-contact voltage tester
- Masking tape
- Needlenose pliers
- Wire strippers
- Electrician's tape
How to Replace an Outlet Receptacle
In most cases, replacing a receptacle is a straightforward process of disconnecting the circuit wires from the old receptacle and attaching them to the new receptacle in exactly the same fashion. The job normally takes no more than about 15 minutes. But depending on the age of receptacle, the age of the wiring installation, and other factors, the configuration of wires within the box may vary widely. For example, in some older wiring installations, the system may not have a grounding wire, and may instead be grounded through metal conduit.
Don't be surprised if the wiring looks different than the description in our example, and if you have trouble understanding what to do, call in a pro.
Our example presumes that your receptacle has been wired with the accepted modern practice, using NM (non-metallic) cable, and that the receptacle has white (neutral) and black (hot) connections made using screw terminals. Our example also features a bare copper grounding wire that connects to a green grounding screw on the receptacle.
- Shut off the power to the receptacle by flipping the circuit breaker controlling the circuit to the OFF position at the main service panel. Do not assume that the index in the panel is correct; always check for current.
- At the outlet location, use a voltage tester to check for power. No-contact voltage testers sense current without touching any wires. But make sure your tester is operating correctly by first testing it on an outlet receptacle you know has live current.
Once you are sure the receptacle has been shut off, remove the center screw on the outlet face plate, using a manual screwdriver.
With the cover plate off, test for power again by inserting the probe of the circuit tester into the spaces alongside the body of the receptacle. Use a flashlight to find the side of the receptacle where the black (hot) wires are connected. The black wires are normally the "hot" wires, although there may be instances in which the hot wires are red, or where they are covered with insulation without a distinct color. Whatever colors the wires are, the hot wires are usually connected to the brass-colored screw terminals on the receptacle. Test these wires with the circuit tester. If the wires are dead, you can proceed with the replacement.
Remove the mounting screws holding the receptacle strap to the wall box, and gently pull the receptacle out of the wall box, gripping the receptacle by the top and bottom "ears."
Examine the wire configuration. In most cases, you will see three wire colors attached to the receptacle: black wires are "hot" wires that carry live voltage, usually attached to brass-colored screw terminals; white wires are neutral wires, usually attached to silver-colored screws; the bare copper (or sometimes green insulated) wire is the ground wire, attached to the green grounding screw on the receptacle.
Verify the proper amperage for the new receptacle. If the circuit has been wired correctly, a 15-amp circuit should be wired with 14-gauge wire. This circuit should be wired with a 15-amp receptacle. A 20-amp circuit should be wired with 12-gauge wire and a 20-amp receptacle. If you find a contradiction in the wiring—for example, if a 20-amp circuit breaker is feeding wires that are only 14-gauge, it's time to call a professional, as you have a potentially dangerous situation. If circuit breaker, circuit wires, and receptacle all are consistent, you can proceed.
Use small pieces masking tape to tag the wires that are connected to the "hot" (brass-colored) screw terminals. Some receptacles will have only one hot and one neutral wire attached to the receptacle, while others may have a pair of hot wires and a pair of white wires attached to the sides of the receptacle. How your receptacle is wired will depend on where the receptacle is within the circuit configuration (middle-of-run or end-of-run), and on how the previous electrician chose to wire the circuit. Either way, your goal will simply be to recreate the same wiring connections on the new receptacle.
Disconnect the old receptacle. Receptacles have two methods of connecting the wires: screw terminals on the sides of the receptacle, or push-in "back-wire" slots in the back of the receptacle. Most electricians believe that the screw terminal connections are more secure, and they usually avoid making back-wire connections. If your old receptacle has back-wire connections, remove the wires by inserting a small nail into the release slot next to each wire. The wire connection should loosen and pull free of the receptacle body. If your receptacle has screw terminal connections, loosen the screws and remove the wire loops from around the screws.
To begin installing the new receptacle, attach the bare copper or green insulated circuit wire to the green screw terminal on the receptacle. To do this, bend a C-shaped loop at the end of the wire, loop it in a clockwise direction around the green screw terminal on the receptacle, and tighten the screw firmly.
Attach the white neutral circuit wire(s) to the silver-colored screw terminal(s) on the receptacle. Form a C-shaped loop at the end of the wires, loop them around the silver screw terminals in a clockwise position, and tighten the screws firmly. NOTE: Some receptacles are designed so the straight ends of the wires are inserted into slots next to the screw terminals on the side of the receptacle.
If you prefer to use the back-wire fittings, the simply insert the neutral wire(s) in the neutral slots in the back of the switch. Make sure no bare wire is exposed, and tug on the wires gently to make sure they are secure. You may need to trim down the ends of the wires slightly so that no excess bare wire is exposed.
Attach the black (hot) wires to the brass-colored screw terminals (or the hot slots on the back of the receptacle), in the same fashion as you used to attach the white neutral wires.
Wrap a loop of black electrician's tape around the sides of the receptacle, covering the bare screw terminals. This is an electrician's trick to prevent accidental contact with the screw terminals.