Installing a 3-Way Dimmer Switch Installing a 3-Way Dimmer Switch

Installing a three-way dimmer switch on an existing 3-way switch circuit is not only a simple job, but it will add flexibility to your lighting design and improve the overall atmosphere of your living space. The primary thing that confuses most do-it-yourselfers is the fact that only one of the three-way switches needs to be replaced with the dimmer switch. If you replace both current 3-way switches with two three-way dimmers, the circuit won’t function properly.

So, your first step is to think about which of the two switches you use the most. This is the one that you should replace with the dimmer.

Here’s how to replace an existing 3-way switch with a 3-way dimmer switch.

Step 1: Turn off the power to the circuit.

Step 2: Remove the cover plate from the switch.

Step 3: Remove the two screws that secure the switch to the wall box and gently pull the switch out. Double check with a voltage tester that the power is off.

Step 4: Position the switch so that the side with the two screws is facing your right.

Step 5: Hold up the 3-way dimmer next to the existing 3-way switch in the same manner.

Step 6: Remove the RED wire from the existing 3-way switch and connect it to the same place on the dimmer switch. In most wiring applications, the RED is connected to the single screw on the left side of the switch.

Step 7: Take the wire that is connected to the DARK screw on the right side of the existing switch and connect it to the DARK screw on the new dimmer switch.

Step 8: Remove the last wire on the switch and connect it to the bottom screw on the right hand side of the dimmer.

Step 9: Connect the ground wire to the ground screw on the dimmer switch.

Step 10: Wrap the dimmer’s terminals with electrical tape and install it into the wall box.

Step 11: Install the new cover plate and turn the circuit back on.

That’s all it takes to replace an existing 3-way light switch with a more innovative 3-way dimmer switch!

Dave Donovan is a freelance copywriter living in Atco, N.J. An electrician for 15 years, an injury forced him to pursue his true passion - writing.

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