It is best to install a four-way switch during a house's construction, as the switch's circuit requires a special kind of wiring. Existing circuits can be modified to accommodate a four-way switch, but experts recommend hiring an electrician to do this. Shut the power off before undertaking any work with electrical wiring. To keep the wiring simple, feed AC power either to the light fixture or to the first switch in the circuit.Continue Reading
Shut the power off, and run 12-3 or 14-3 wiring through the switch's location. Check the light switch packaging to find out how the wire should run through the circuit. Connect the supply wire to a three-way switch, and connect the three-way switch to the four-way switch. Next, connect the four-way switch to a second three-way switch, and mount all of the switches in their respective electrical boxes. Check the switches' packaging to ensure that the wires are correctly connected.
While it is generally easiest to have power enter the circuit at the light fixture or the first switch, there are many possible wiring configurations. The power may run from switch to switch to fixture to switch, or it may enter the light fixture and run to the switches in opposite directions. If you add additional light fixtures to the circuit, run them in parallel to the original light. If you need to add additional switches, the switches should be four-way.Learn more about Electrical