Q&A for How to Wire a Double Switch

If your wires were installed by a professional, the white wires are almost always going to be neutral. All of those neutrals get spliced together.

This issue can occur if a traveller is mixed up with the line feed; or if only a 2-wire was pulled between the two switches; or where the feed comes to the light first, and the two switches aren't linked correctly. Because this level of troubleshooting requires a live circuit to determine what's what, call a qualified electrician to do this repair.

You will need an additional wire up to the fan.

It's possible that the switch you removed was one of the two that controls the non-functioning light. A switch with three wires could be used for a hall light with a switch at each end. The switch puts power out to one wire or the other, like a valve for water that goes in two directions.

Connect the one black wire to the bottom dark screw of the other already wire configured switch. Essentially, 2 black wires are attached to the bottom dark screw of one switch. It is one black wire from the power source (hot wire) and a black wire from the neighboring switch.

It's not typical for black power lines to be reversed in a double wall light switch setup. Usually, both black wires are connected to the same terminals on each switch. However, if the switches are wired in a "backstab" configuration, one black wire might be on the top connection of one switch and the other black wire on the bottom connection of the other switch. Wiring can vary, so follow proper procedures and consult a licensed electrician if you're unsure.

To connect four red wires in a double switch setup, first identify the circuits by tracing the wires back to their sources or using a voltage tester. Group the red wires from each circuit, then connect one group to the "line" terminals of one switch and the other group to the "line" terminals of the second switch. Connect the corresponding black wires to the "load" terminals of each switch, and join any neutral and ground wires securely. Always prioritize safety and consult a licensed electrician if unsure.

First be sure the power is off at the breaker box. Identify the wires in the wall box; the black wires are usually the hot wires. Remove the old switch, noting the wire connections. Install the double switch per manufacturer instructions, connecting the hot wires to one side and the wires from the lights to the other side. Use wire nuts and electrical tape for secure connections. After reestablishing power, test the switch. Consult a licensed electrician if you have any doubts.

It sounds like you have a single pole switch controlling two fixtures, and you want to convert it to two switches, each controlling one fixture. Here's how you can do it: Turn off the power at the breaker box before starting. Identify the wires in the wall box. Typically, black wires are hot, white is neutral, and red is the switched hot wire. Install two single-pole switches. Connect the black wire from the power source to the common terminal on both switches. Connect the red wire to the switched terminal on one switch and the white wire to the neutral terminal on both switches. Connect black fixture wires to switched terminals on corresponding switches and white fixture wires to neutral terminals. Use wire nuts to secure wires and wrap them with electrical tape. 6. Turn the power back on and test the switches. If unsure, consult a licensed electrician for assistance. Safety is the top priority.

If you have two red wires, you may need to splice them together depending on your specific wiring setup. Here are some scenarios: 1. **Two Red Wires from Different Circuits**: If the two red wires are from different circuits or sources, they should not be spliced together. Each red wire should connect to its respective terminal on the switch or device. 2. **Two Red Wires from the Same Circuit**: If the two red wires are from the same circuit, they may need to be spliced together for continuity. Use a wire nut or appropriate connector to join the two wires securely. 3. **One Red Wire as Hot and One as Switched Hot**: Sometimes, one red wire may be the hot wire, and the other may be the switched hot wire. In this case, they should not be spliced together. The hot wire should connect to the appropriate terminal on the switch, while the switched hot wire should connect to the terminal that controls the load.