Combination devices are a convenient way to add either an additional switch or receptacle on a circuit. Removing the original electrical box from the wall to accommodate a combination device is not necessary as it will fit in a single gang electrical box. When installing a combination device in a kitchen or bathroom, you should install at least one ground fault circuit interrupter (GFCI) receptacle on the circuit. A GFCI is a trip switch that senses any shock hazard and shuts off the circuit.
Turn off the circuit that supplies electricity to the GFCI receptacle and light circuit by turning off the circuit breaker in the main electrical panel.
Use a wire cutter/stripper and cut one 15 cm (6 inch) piece of 12 gauge solid thermoplastic high-heat nylon-coated (THHN) green wire and one 15 cm (6 inch) piece of 12 gauge solid THHN white wire. Strip 1.2 cm (1/2 inch) of the insulation off both ends of the white and green wires.
Connect the pigtail wires to the wires inside the combination GFCI receptacle and light switch electrical box. Locate the two white wires inside the electrical box and connect them with the white pigtail using a red wire connector. Locate the two bare copper wires and attach them to the green pigtail wire with a red wire connector.
Connect the combination GFCI receptacle and light switch into the electrical box. Position the device where the combination switch is at the bottom and the GFCI receptacle is at the top. Wrap the white pigtail wire around a screw on the top left of the combo device and tighten the screw. Wrap the green pigtail around the green screw on the combo device and tighten it. Wrap the black power supply wire around a screw on the right side of the combo device. Wrap the remaining black wire around the screw to the left of the switch on the combo device. Tighten the screws to hold the wires to the device. The power supply wire feeds electricity from the breaker to the device.
Push all the electrical wires into the electrical box and connect the combination GFCI receptacle and light switch to the box with screws at the top and the bottom of the combo device. Cover the device with the single gang rocker switch plate cover.
Turn the breaker back on in the electrical panel that powers the GFCI receptacle and light switch circuit.
Test to verify that the electricity has been disconnected in the area that you are working to avoid electrical shock.