Smart Light Switch No Neutral

Ok, so my house does not have neutral wires at the switches. I know there are switches that will work without neutral, but they are for incandescent bulbs. I believe, if I understand correctly, that these work with incandescent and not LED because there is always a small amount of power in the circuit to keep the switch awake. This small amount of power is enough to keep an LED lit, but not an incandescent.

Now, my question is this… I have a single circuit in my bathroom with a switch. On this circuit is 3 A19 LED, and a bathroom fan. Would one of the non neutral switches work in this situation as it takes much more load to turn things on in this circuit compared to one with a single LED bulb?

1 Like

Unlikely. Your best bet is to go with connected bulbs rather than switches if you don’t have neutrals.

1 Like

If only it were that easy.
I could swap the bulbs, but I would have to leave the switch on, which would make the fan stay on all the time.
I do not want to hardwire anything, and I was trying to avoid one of the modules that go in the wall.

Well, yeah, that would be a problem. Bummer. You might be forced to get an electrician to run a neutral.

Wait, here’s an idea! Assuming your fan is wired directly into the mains, you could remove that and replace it with a regular three-prong cord, put in a switch box with an outlet (in your ceiling or attic), get a smart plug, plug that into the switchbox, and plug the fan into the smart plug! :wink:

1 Like

What’s wrong with module inside the wall? I think that’s your best solution without neutral. Micro switches at light fixture.

1 Like

I want a nice new switch.
Also, a little confused with how the module would work with the 3 light fixture and the fan.

I like your thinking, but that sounds a little sketchy. Thanks for thinking it through though.

You install the micro switches at the light fixture/fan gangbox assuming you have neutral and line hot there and control the micro modules with your old non-smart switches. You can use any cheap on/off switches. Just not dimmer.

1 Like

Don’t you still have to run a wire from them down to the switch though?

It’s already there with your old wiring. That’s how you control your old light in the first place.

Edit : here’s a link to an Aeon micro. There are other brand out there as well

1 Like

This is what I read about those switches.
“Power comes into the ceiling box, goes into the micro switch, then comes
out of the microswitch to the light. Then, you wire the two wires that
go down to the wall switch to the remaining two connections on the micro

But wouldn’t I have 1 wire going down the wall to the switch?
I assume it is 1 wire into switch from breaker, then one out to light, then 1 out of light back to breaker to complete the circuit.

Here’s a reference single pole wiring. Since you have no neutral at the switch. Most likely you have the second drawing.

I was being facetious, of course. But yeah, if you wanted to you could probably put one of those micro switches into the switch box that the fan is wired into. That and 3 smart bulbs, and Bob’s Your Uncle!

I got a GE switch from Lowes. It was the last one they had. With the 3 LEDs and fan, they flicker when turned on or off. I replaced one of the LED’s with an incandescent and it works great. Only issue is I can’t get Smartthings to find the switch.

Ok, got it all working, thanks for the help.

It might be worth talking to an electrician on site at your house. I’ve had wire pulls I thought were going to be a nightmare and the electrician pulled the wire and still had time to install the switches I supplied within the initial hour of time. The guys who do that stuff everyday often don’t give it a second thought whereas we think something is almost impossible. Just a thought.


Very good advice. I used to do this stuff for a living and if there is a crawl space or attic. I could pull the wire and get the light working less than an hour. Pulling just a neutral is even easier.

1 Like

That one is for a completely separate home automation system and is not compatible with SmartThings. It requires its own hub and I didn’t see any integration option.

(Also, I may have missed it, but it doesn’t look like it has any of the standard third-party safety certifications, such as UL listing. )

I don’t think it’s what most people in this forum are looking for. This forum is for people who have the SmartThings system.

Is there a SmartThings integration?

1 Like

© 2019 SmartThings, Inc. All Rights Reserved. Terms of Use | Privacy Policy

SmartThings; SmartApps®; Physical Graph; Hello, Home; and Hello, Smart Home are all trademarks of the SmartThings, Inc.