How do I replace a dimmer switch in a double switch?

Question

There is one switch for a ceiling fan and a dimmer switch for a light. The fan works. I removed the old switch which had three wires connected to it. One black wire from the wall paired with a black wire from the fan switch connected to one post on the dimmer switch and one black wire from the wall connected to the other dimmer switch post. I connected the wires the same way to the new dimmer switch. The new dimmer switch came with a ground wire that I connected to a green wire in the box. After all this, the fan works, but the lights controlled by the dimmer switch doesn't work. I tried switching post on the dimmer switch, but it still doesn't work. Am I missing something?

Answer 1

You can not use the s***w terminals on a switch/receptacle as a junction.  You need a "pigtail" - a short length of wire (4-6") connected to each switch, and the pigtails from each switch connected to the source ("hot" lead) with a wire nut.

In using the terminal as a junction, maybe the you've got insulation under the s***w, so the dimmer's not seeing power.  Aside from that your install sounds standard, I don't see where you might have miswired anything.  If this is a mechanical dimmer (k**b or slider), it doesn't matter which way the wires are connected.  If it's an electronic dimmer, they sometimes have a specific "load" and "source",  they often require a neutral connection as well.  If your dimmer requires a neutral connection, and you don't have a neutral in this box (light switches are sometimes wired with power going to the light first, and only a hot "switch leg" coming down to the switch), you're stuck.  You'll need to get a dimmer that does not require a neutral (or else find a way to bring a neutral into that box).

Answer 2

Why do people mention wire colors when they have a question about electrical?

Do they really think the electricity knows what color the wire is?

Yes, it is true if the last guy did it right black, red, and other none white wires should be hot, and maybe white is the neutral.

But white can be hot in 220v loads or switch loops and every house in america has 220v loads or switch loops.

It is completely code for the white to be the hot wire some times

and if the ast guy was a D.I.Y then all bet are off

I am a Master electrician with over 13 years in the trade

Answer 3

Turn the light on at the fan?????  Or there may be an on/off switch that needs to be turned on on the dimmer