I’ve now done a few GE and WEMO switches and all have been pretty straight forward. Even the 3 way switches were really easy to figure out. But I’ve run into one that’s a bit odd.
I went to add a GE smart switch for my garage lights and saw something I’ve not run into before. There are two switches in the box for two different circuits. The switch for the garage lights has a red wire and black wire connected to the copper contacts and a ground. This is the only switch for the garage so I was surprised to see the red wire. I went out to the garage and found that the bulb socket had the red and black wire connected to the brass connections and then a white neutral on the silver contact. I’m honestly not real sure how to wire this up. Any ideas?
We might be able to provide some further help if you provided more specifics as I’m not really sure what you are actually talking about. You mentioned 2 switches, but then only talking about 1? You said garage lights and then bulb?
Anyway, I can make some assumptions so here goes:
I’ll assume this other circuit you mention at the beginning is completely irrelevant, and that you likely have a black and a different color (not red) attached to it. The secondary color doesn’t really matter of course, but a good electrician wouldn’t have used the same color load to two locations in a single room.
I’ll assume “garage lights” and “bulb” refer to the same entity, either inside the garage, or outside the garage as some refer to their exterior lights on the garage as “garage lights” as well. Each light requires a hot and a neutral to function, that’s why you see a white at the light bulb, but not at your switch. You simply have a case of not having a neutral wire at the switch location, which is still pretty normal.
Depending on the GE switch you purchased, you might need this neutral at the switch location. Make sure you don’t have a group of white wires coiled together in the back of the box, not tied to a switch, this is also common to see.
Finally, the black at the switch is your “line” or “hot”, the red is your “load”. So on a traditional switch, when actuated, you are connecting the black and red wires through the switch, sending power to the lights, and then the neutral carries it back to your breaker. Because of this, the only “odd” thing in your setup is having the black wire at the light bulb. The most likely scenario here is that you have another light bulb that is controlled by this switch, so when power is sent down the red wire from the switch, is is transferred to the black wire at the bulb, to the next bulb in the sequence, which also has a white wire tied to it.
Short answer, you really probably want a neutral (white) at the switch location but that isn’t always feasible. I know there are ways of doing it without one, but I have never had the need. Poke around the forums, like @Ben said and search for switches without neutrals. I’m guessing that it’d have to be an incandescent bulb though at the very least.
What you’re describing sounds really typical for a 1960s or 1970 US double switch without a neutral.
Remember that in the United States, wire colors are not mandated code. People can and do use whatever bits of wire they have lying around.
For a while, you used to see red as the hot wire coming into the switchbox, black as the load going from one of the two switches to one device, and white as the load going from the other switch to its device.
Note that this is not a three-way switch. It’s not that both switches control the same device. Rather it said there are two devices on the same circuit, each with its own switch. Really commonly used for, say, a bathroom light and fan. In the garage you would sometimes see this set up for interior lights on one switch and exterior lights on the other. You also see it in utility closet that had one switch for an overhead light and another switch for some device in the closet, typically a water heater timer. You also sometimes saw this for pools, one switch for the lights and one for the pump.
I want to emphasize again that there is no neutral at the switchbox in these configurations. But there has to be a neutral someplace to return the current to the circuit box, and that most typically was done at the light fixture and the other device that is sharing the same circuit. Doesn’t really matter where it is, it just has to be somewhere.
Here is one diagram of this model. It’s a dual switch in a utility closet or basement, one switch controls a fan, the other switch controls the light. No neutral at the switchbox: the neutral is at the light fixture.
I can’t say for sure that this is what you’re seeing, but it sounds like it.
Red is the hot coming into both switches. Black is the load out from one switch and white is the load out from the other switch. However some people would use black for both of these. And starting around 1980 the colors were usually done in reverse, with black used for the hot and red used for the load to the light fixture, but again there’s no code requirement and people can do it however they want. And just for fun, but again really really typical, white is also used for the neutral that connects at the light fixture. So to “avoid confusion” The white line in from the switch to the light fixture gets taped black where it comes into the light, so now the light fixture has a black wire in which is the same as the white wire coming out from the light switch. And the light fixture has a different white wire going out.
(All because electrician kits used to just have White, red, and black wire. In the 21st-century if we were designing national code to address wire colors we’d probably have eight different colors and use each one consistently. But in the United States we do not have required wire colors. So always tread carefully.)
Anyway just one possibility. You need to test all the lines to be sure. I know you said the second switch was a different circuit, which would make the wiring a little different, but the same model might apply as far as red in, black out, neutral at the fixture. (Having two different circuits in the same switchbox adds a whole bunch of wiring issues, and you don’t usually see it these days, but people did used to do it so you can run into it occasionally.)
Also, I know you’ve already looked at this but just for completeness while we’re adding other links, we should include the link to the wiring FAQ:
Thanks for all the information. I eventually figured it it after some reading and thinking. The red wire was load, black wire was line. There was a natural bundle in the dual gang box so I used that as well. The 3 way switch in the same box was installed without issue.
Now I’m on to the next fun one. This is a 3-way setup on either end of a hallway. The two switches control a single light fixture.
Switch 1: Two black wires, a red wire and ground. This switch sits in a dual gang box with another 1 way switch. There is a neutral bundle in the box.
Switch 2: This switch has two black wires, a red wire and a ground. It’s the only switch in a single gang box and there is no neutral.
I replaced switch one with a GE12724 Dimmer and it’s working fine.
I planned to replace switch 2 with a GE12723 auxiliary switch but there is no neutral and I believe it’s required. I tried it with just the red traveler and ground with the black wires ties together with a wire nut. That didn’t work. But, like I said the primary dimmer works.
Rule 1: if the manufacturer says the switch needs a neutral, the switch needs a neutral. You either use a different switch, or fish up a neutral.
Before going on to the next set, though, can you verify whether in fact the two switches in one box from your previous question were two different circuits? Or were they controlling two devices on the same circuit?
Because if they were indeed two different circuits, stop now and call in a licensed electrician to check your wiring. Making those safe can be really tricky.