How to Dedicate an Outlet Just for a Dishwasher

Turn off the power to the circuit that you're connecting the new outlet to by flipping the breaker or removing the fuse at your home's main electrical box.

Remove the plate cover from the outlet to which you're going to connect the new outlet. Unscrew the mounting screws at the top and bottom of the outlet, and pull it out of the wall by grasping the metal tabs that the mounting screws were attached to. Take care not to touch the wiring or the sides of the outlet until you can test the circuit.

Test the circuit with a voltage tester. Place one of the leads from the voltage tester against the bare copper ground wire, and touch the other lead against the terminal screws on the side of the outlet. If you get a reading on the voltage tester, stop what you're doing and return to the main box. Shut off the proper circuit, then return to the outlet and test it again. If you don't get a reading, you can continue.

Trace an old-work outlet box onto the wall where you're installing the outlet for the dishwasher. Cut a hole in the wall with a drywall saw.

Feed a 12/2 electrical cable between the outlet you removed and the hole in the wall for the new outlet. The 12/2 indicates that the electrical cable contains two 12-gauge wires, one covered in white insulation and one covered in black insulation, as well as a bare copper ground wire.

Remove the knockout holes from the back of the old-work outlet box, and then slide the cable through it. Insert the box into the hole inside the wall and screw it to the wall.

Strip 2 inches of sheathing from the electrical cable with wire strippers and 1/2 inch of insulation from the wires inside the cable.

Bend the exposed ends of the black and white wires into a hook with pliers. Hook the wires onto the terminal screws on the sides of the new outlet and tighten the screws. Connect the black wire to the brass screw and the white wire to the silver screw. Connect the ground wire to the green ground screw on the bottom of the outlet.

Slide the outlet into the outlet box, and then screw it into place with the mounting screws. Screw the plate cover onto the outlet.

Connect the black and white wires from the electrical cable to the outlet you're connecting to using the same process you used for the new outlet.

Cut a 3-inch piece of bare copper wire from the excess cable. Unscrew the ground wire from the first outlet, and connect one end of the 4-inch wire to the ground screw. Connect the opposite end of the 3-inch wire to the ground wires from the two electrical cables. Twist the three wires together a couple of times with pliers, then place a plastic connector cap over the wires and twist it two or three times.

Tuck the wiring into the wall, then slide the outlet into the electrical box. Reattach the mounting screws to secure it in place, then replace the plate cover.