3-way setup (LZW30-SN) with dumb switch


I am trying to replace a 3-way switch for my hallway lights. Box A (red) is upstairs where the light is, and Box B (white) is downstairs. I’ve read over the wiring diagrams more than a few times and finally believe that I have 3-wire in both boxes. So I am a little unsure how to wire up the Innovelli? and if I should put in in box A or box B? Help appreciated!!

Using a voltage meter,

Box A - Red wire is hot, black is not.

Box B - Red wire is hot, black is hot

Box B

It’s a little tough to see into your boxes. Do you ONLY have one 3-wire (i.e. black, white, red + bare ground) in each box? That looks to be the case but you’ll have to confirm, as I can’t really see into the white box.

If you ONLY have a 3-wire in each box and no other Romex, then you have a power to the light with one 3-wire going to each switch box from the light box. If that is the case, you have a non-neutral configuration and you won’t be able to use a LZW30-SN, since switches require a neutral. You can use a dimmer, however, in a non-neutral configuration. If you want to proceed in that direction, post back and we can explain how it’s wired.

Hi @Bry

Yes, I only have one 3-wire in each box. When I looked at these before ordering, I saw a white and assumed it was the neutral. :confused:

Okay so I’ll have to swap out for a non-neutral dimmer. Once I do, I’ll post back. Can you explain how it should be wired up?

Yep. He me back. As you figured out, the white isn’t always a neutral.

BTW, you are also going to need an Aux for the other switch. You can’t use a dumb switch with a non-neutral.

Here’s one of your old solutions


As you figured out, the white isn’t always a neutral.

Yeah and I should’ve known better, house was built in 1923 and electrical was updated in 2000. I bought it 2015 and started automating. I ran into the non-neutral issue once before on a different set of switches. So I don’t know what I was thinking.

I think I will wait for the Red Series dimmers to come back in stock. Maybe, just maybe I can get lucky and find a neutral wire downstairs. I had that re-wired not too long ago.

@stu1811 Thanks for the link.

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