I am trying to replace a broken dimmer switch. There are 2 dimmer switches in this particular electrical box. The replacement switch I bought has 4 wires (2 red, 1 green, 1 black) but the switch I am replacing only has 2 wires, both black, and they are wired to black wires in box. Trying to figure out how to wire this; any help would be appreciated !

 

Welcome to the forums.

Can you leave us a link to the dimmer you have..... or the model number ?
It sounds like you have a three way dimmer with a single pole circuit.

OR.... do you have black, red, red with orange stripe and green ?
If this is the case.... black goes to HOT. Red goes to LOAD. Cap off red/orange. Green is ground.

 

Many dimmers sold these days can be used for both single-pole and three-way configurations. It would have been helpful if you posted the model of dimmer you bought and I suspect you also have some directions that came with the switch, but we can wing it anyway.

The green wire is connected to the ground (bare) in the box.

Your existing switch is a single-pole so you only need to use two of the other three wires. I suspect one of the reds has a white stripe so I would just cap that one off with a wire nut.

The black wire connect to the group of black wires under the yellow wire nut.
The other red connect to the single black wire in the box that is connected to the dimmer you are replacing.

Test this setup and see if it works. If not, post back and we can continue from there.

 

Thanks so much; worked like a charm !

 

Thank you, I was able to fix it with this information !

 

Awesome! Thanks for reporting back.