If your home was wired before codes required ground fault type GFCI outlet in bathrooms, kitchens and the outside of homes. It might not be a bad idea to install them for safety's sake. This is how to wire a GFCI outlet.
What is a GFCI Outlet
GFCI Outlet or Ground Fault Circuit Interrupter Outlets are also called GFI Receptacles. These outlets are easy to install or replace. The GFCI outlet provides safety from shock hazard by detecting loss or compromise of the safety ground. They are required in kitchens, bathrooms, outdoors or anywhere near water. Some states now require that they be tamper proof, check with your local electrical codes to determine that they need to be tamper proof. They come in two different current ratings. You need to select the current rating according to the wire size you are using. A 15 amp outlet would connect to #14 gauge wire and a 20 amp outlet connects to #12 gauge wire. Be sure to turn off the power at the breaker box before working on any outlets.
Ground Fault Circuit Interruptor GFCI Outlet Picture
How To Wire a GFCI Outlet
If you look at the back of a GFCI outlet you will see that it is labeled Line Side and Load Side. The Line Side would connect to the power source, such as a breaker box. The Load Side would connect to other outlets and device fixtures on the same circuit, such as bath fans or lights. Anything connected on the load side would be protected by the GFCI and will cause the ground fault outlet to trip if a ground fault is detected. It is not advisable to have two GFCI receptacles on the same circuit. Be sure to match the GFCI outlet to the current rating of the wiring, 20 amps for #12 wire and 15 amps for #14 wire.
GFCI Won't Reset
What to do when A GFCI keeps tripping and won't reset.
Some problems I have found with GFCI outlets not resetting can be caused by a few factors. 1. The outlet itself is defective. 2. Something on the circuit is causing it to trip. If this is the case you need to isolate the problem by removing the wiring from the load side and then seeing if the outlet continues to trip. I have seen where CFL lights, fan motors and even plug air fresheners have caused this problem. Check the spec sheet on any GFCI's you plan on buying to make sure that they are compatible to use with CFL's or LED bulbs, as many are not and will keep tripping. I recommend keeping lighting and receptacle circuits separated. Update: I recently contacted tech support at Leviton. They assured me that their GFCI outlets were compatible with CFL and LED lighting. They specifically recommended model N7899-W for residential use.
How To Test GFCI Outlet
There are really two ways to test a GFCI outlet. The first method would be to simply press the test button on the front of the receptacle, if it makes a click sound and pushes out the reset button all is probably well. The second method involves a plug in circuit tester that will test the gfci receptacle dynamically. The tester pictured below will test both GFCI and standard outlets. Remember, GFCI's eventually will go bad and need to be replaced. Manufacturers recommend testing monthly.
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