We’re looking to replace a light switch at the top of the basement stairs. It’s a horizontal-flip switch with a light bulb indicating “On”. The switch operates a light in the basement next to the boiler. We want to replace the existing switch with one that has an LED bulb instead of incandescent. When we pulled the switch were surprised to see four screws: one black, one brass, and two silver, with five wires going to it: one to each of the black and two silver, and two going to the brass. I say “surprised” because we’re not aware of any other switches on this light.
This switch is in a two-gang box. The other switch is a three-way for the basement stairs (pictured). Interestingly, with the boiler light switch disconnected, the basement stair switch is inoperable. Pictures show the old and new switch. Question is: can the new switch be wired to operate the single-bulb boiler light (with LED working) *and* keep the stairway switch operational? (Sorry, but this web site rotated the old switch images.)
Replies
On the new switch the black is your line hot the brass is your hot to the boiler light the silver is your neutral which you need to light the led indicator light and the green is your ground. You need to find those wires in the box and how they are located via the stair switch. If you cannot determine those wires yourself I really suggest in the interest of safety you hire an electrician
bing, if it's not straightforward to describe than your advice is probably best.
The answer to your question is, of course, yes. But to get there, a bit of a puzzle to solve.
The challenge is to understand where the wires that come into the box come from, where they go, and what they do.
A first guess is that the brass screw on the old switch is the power feed, which is tapped with the second wire to power the three way light circuit.
as you solve the puzzle, you cannot rely upon the color of the wires to reliably indicate the purpose.
A meter or other test device will come in handy.
I would pull the adjacent three way switch in the box out a bit to let you see where the wires to that switch connect to, and more clearly see if you can tell how many non metalic cables come into the box. and map wire colors from the cables.
You also might want to take a peek inside the other stair light three way switch, and inside the light box by the boiler.
Did you install the three way switch?
Have you identified the fuse/breaker that feeds these circuits?
> Did you install the three way switch?
Yes
> Have you identified the fuse/breaker that feeds these circuits?
Yes
Lots of ideas there, thanks!
If one were to remove the two wires from the brass screw, would they expect to get 120v with a tester between the wires and ground?
Of those two, if my guess is correct, one would have 120 volts (give or take ten volts), and the other not.
I would expect that if this is the case. one of these wires (perhaps the white one) will go directly to your three way stair circuit.
If you hook them together (use a proper device), the stairs light would work.
One issue is to identify a neutral wire. (which would be at ground potential)
Usually they are white, but in your case, I expect several white wires are not neutral.
How many wires are on the back of your three way switch?
You have a white and a colored wire to the same terminal. There are one or two reasons why this might have been ok at the time (but not now), and a thousand reasons why this is wrong. I can't even guess from the pictures. Some one needs to track down what all the wires are for and where they go. I suggest getting an electritian.
Yes, I think you're right.