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Jason, Service Technician
Category: Electrical
Satisfied Customers: 4280
Experience:  Over 20 years of experience in all types of installations, troubleshooting, and repairs.
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I have a light switch with red, white, black and ground wire,

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I have a light switch with red, white, black and ground wire, am replacingit with a dimmer switch with two wires plus a ground wire what do I do with the extra wire IE the apparant 3 power wire which may be multipled to an adjacent switch on a three switch wall plate. One is for a chandelier, the other a fan which has a light and the dimmer is going to be for recessed lights
HiCustomer Let me make sure I understand you. You are replacing a toggle switch with a dimmer switch and the toggle switch has a red, white, black, and a bare wire connected to it. Is this correct?
Customer: replied 8 years ago.
Yes that is correct
Customer: replied 8 years ago.
In the event my previous reply was not received. The answer is yes, I am replacing a rocker type I guess as vs. toogle with a slide dimmer switch. The existing switch is a recrtangular type that pivots on its center on and off.
Thank you for the additional information. I have one more question for you - Is there a second switch that operates the same set of lights as the switch you are replacing?
Customer: replied 8 years ago.
No the switch I am changing is for a single set of recessed lights. The other switch on the three gang set up are for two other devices. A fan and its slightls and a separtae chandlier. The chandlier is a 3 lead switch, the fan and it's light must be 3 or more, I don't know since I have not removed it.

Please allow me to ask another question - How many screws are on the rocker switch that you want to replace with the slide dimmer? I am talking about the screws that have wires connected to them, and we can ignore the ground wire. Also, it would help me answer your question if you can tell me what colors the screws on the switch are and what color wires are attached to the screws. Thank you for your patience as we work through this.

Customer: replied 8 years ago.
There are 4 screws,one for each of the four leads IE red, white,black, copper wire. Each screw allows you to screw down on each wire connection.l

Thank you. A switch with 3 wires connected to it is a 3-way switch, meaning there should be a second switch somehwere nearby that will operate the same set of lights. You will need to use a 3-way dimmer switch to replace the existing switch. The 3-way dimmer will have 4 wires coming out of it, with one of them being the ground wire. Of the other 3, there will be 2 that are both the same color and a third that is a different color.


If you look at the existing switch, there should be 2 screws that are the same color (probably gold or brass) and a third screw that is a different color (probably black). Please make note of how the wires are connected to the screws on the existing switch and connect the new 3-way dimmer in much the same way - by connecting the 2 wires that are connected to the 2 screws that are the same color on the existing switch to the 2 leads from the 3-way dimmer that are the same color. This leaves one more wire from the wall and one more short lead from the 3-way dimmer, simply connect these last 2 wires to each other and you should be good to go.

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