We have two dimmer switches in a finished basement room. Switch 1 controls wall lights, and Switch 2 controls overhead lights.
We are hoping to replace them with smart switches that require a neutral.
It looks as if Switch 2 is wired using a switch loop. (The white wire connected to Switch 2 is wrapped in black electrical wire, to indicate that it is being used for that purpose.)
From what I understand, the switch loop is an obstacle to using a smart switch, because the neutral wire is being repurposed.
What I'm wondering is whether it's possible to rewire (ideally without having to run new wire) to take advantage of the fact that there is a true neutral that is accessible within the box from the cables that are connected to Switch 1.
Best Answer
Can’t do it.
There’s a “Great Wall of China” between the left switch (and its cables) and the right switch. You cannot cross that with any wire, except safety ground.
It’s a Code violation, it’s a safety hazard to workmen working on the left circuit... and what’s more, if there are any GFCIs or AFCIs in either circuit, it will trip them.
What you might be able to do is reverse flow.
Depending on load factors, you might be able to flipper-oonie (that’s a technical term) the right-side lamp circuit so it isn’t powered at the lamp anymore. Cap off that supply at the lamp. Then flip this former “switch loop” so it is not a switch loop and powers the light in the normal way.
By “load factors” I mean you’re now throwing all of that light’s current onto the left circuit. If it’s a large light, that could be a provisioning issue.