A GFI (ground fault circuit interrupter) is an electrical receptacle that has its own circuit breaker. GFIs are installed in areas where there is a greater probability of electrical shock caused by water. Kitchens, bathrooms and outdoor areas usually require GFIs by code. When used with certain appliances like hair driers and space heaters, over time the GFI becomes much more sensitive to small variations in current, causing it to trip (cut out) on a constant basis. At this point, the GFI has worn out and will need to be replaced.
Turn off power to the GFI at the main electrical panel.
Take off the receptacle face plate by removing the two small screws. Then remove the screws holding the GFI to the receptacle. Carefully pull out the GFI from the box.
Look for moisture in the box, or on the receptacle. If any exists, this can cause the GFI to trip. Remove the moisture with a rag, and reinstall the GFI into the box. Also check the electrical device powered by the GFI. If the device itself has a short, this in itself can cause the GFI to continue tripping. However, if neither of these things exist, replace the GFI.
Check that the power is off. Then loosen all terminal screws on the back of the GFI, and remove the black and white wires. The green (ground) wires should be attached to the back of the box. If there are two black wires, separate the wires, and turn the power back on. Attach a circuit tester to one of the white wires, and one of the black wires. Then attach the tester to the other set of black and white wires. The set of wires that makes the tester light is called the line; the other set of wires is called the load. Turn the power off.
Attach the two line wires to the terminals marked LINE (black wire to the gold colored terminal, white wire to the silver-colored terminal), and attach the two load wires to the terminals marked LOAD (again, black to gold terminal, white to silver terminal). This is done by wrapping the bare wires around each terminal screw, and then tightening the screw.
Push the wires into the back of the receptacle box, as well as the GFI. Reattach the GFI to the box with the two screws, and then replace the receptacle face plate by attaching the two small screws.
Turn the power on. Press the "Test" button on the front of the GFI. The breaker inside will trip. Then press the "Reset" button, which will reactivate the GFI.