Learn how to Wire A Light Dimmer Switch
A dimmer switch gives you way more control over your lights than you may get with a flip switch. In addition they save energy and extend the life of your light bulbs. Dimmer switches are only to be used with incandescent lights. Do not use them with ceiling fans, appliances or fluorescent lights because you’ll destroy the dimmer and whatever it’s connected to. Dimmer switches can replace either single-pole or three-way switches. Follow the steps below to learn to replace both types.
Things You may Need
Turn off power to the light circuit. Remove the cover plate from the light switch and then remove the light switch from the electrical box.
Replace a single-pole switch with a single-pole dimmer. Loosen the two terminal screws on the switch and take away the connected wires. Splice those same two wires to the 2 wires from the dimmer. If both dimmer wires are black, it does not matter how you connect the wires. If one dimmer wire is black and the other red, it is best to splice the black wire to the wire that brings the electricity from the service panel and the red wire to the wire that runs to the sunshine fixture. In case your dimmer has a bare or green ground wire, splice that to the bare wire from the service panel. Cover all splices with wire nuts, push the wires into the box and screw the dimmer to the box.
Replace a 3-way switch with a three-way dimmer. The presence of a 3-way switch (a switch with three screw terminals, not including the ground terminal) means that there is another three-way switch on that same circuit. Only replace one of these, it does not matter which. Don’t install multiple dimmer on the same circuit.
Remove the three-way switch from the electrical box and remove the wires from the terminals. Connect those wires to the identical locations on the dimmer switch, push the wires back into the electrical box and screw the dimmer to the box.
Do not replace a four-way switch with a dimmer. You can recognize a four-way switch by the 2 screw terminals on each side. For those who happen to have any such switch, it means you also have not less than two other switches controlling the same light or lights. The two switches on either end of the circuit are three-way switches. Replace one of those switches with the dimmer.
Tips & Warnings
Always buy “heavy-duty” dimmers. When a light bulb burns out, there’s a surge on the line, and this surge can destroy a weaker dimmer.