How to wire Zooz Z-Wave Plus On Off Wall Switch ZEN21 and connect to SmartThings?

I just purchased the Zooz Z-Wave Plus On Off Wall Switch ZEN21 and after I connect using option 1 in the instruction, I manually turned on/off but nothing works. Even the little LED light in the switch did not lit up. Does this mean I wired it wrong? Or, do I have to go into the SmartThings and configure it in there?

So, here’s what I did. I wire the black wire to the Line, white to the neutral, and red to the traveler. This is a 3-way switch wiring – another switch is in my garage.

This is the existing/original wiring looks like.

Looks like a line, load and traveler. Are you sure you have a neutral?

Normally black and white are line and load, looks like you are missing ground and neutral. You may may want to consult a wiring book or an electrician before you do serious damage to your home.


So, you’re saying the white wire I have may not be a neutral line. If that’s the case then I can’t use this particular switch, correct? If so, is there any 3-way switch out there that’s available without the neutral line requirement?

Did it turn on and off with the Smartthings app?

If that’s your old switch, then that’s probably not a neutral, even though it’s white. Wire color isn’t actually standarized in the US.

Best thing you can do is read up on home wiring and learn how to use a multimeter. I didn’t know how to wire much of anything before I got my first smart switches, but now I’m comfortable with some of this stuff.

If you don’t know your wiring well enough to be sure of what’s what, you’re potentially risking a shock or fire.

I turned on my SmartThings hub and it couldn’t find it. Again, the little LED light on the switch did not even light up.

Take another photo (front facing) the gang box. If you have neutral, in the back behind your wires in your pic then you will have a bundle of white wires going to one wire nut. this bundle will be where you will add your neutral wire.

Only if you have neutral wire will the smartswitch work.

Having pics showing different angles will be better if you need to contact @TheSmartestHouse to help you witj properly wiring the switch.

Take pics of the wiring of the switch in garage as well.

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The switch isn’t getting power, probably because there’s no neutral connected to it.

I will re-state my suggestion to get a multimeter and learn how to test your wiring with it.

I just verified that the white and red line is a the traveler lines. The black wire is the hot wire. So, does this mean the Z-wave switch will not work since it requires a neutral line, correct?

I went to in the garage and flip the switch down and now the z-wave switch has power but it does not turn on/off the light outside. Plus, the SmartThings Hub did not even detect it. It’s only about 10 feet away.

You have this switch in the wrong place. This switch goes on the garage, which is the “primary” switch location. You’re trying to install it where “add on” or “accessory” switch goes (for a Zooz, this is just a normal switch). Show me the wiring inside the garage box.

Okay, with help from an awesome person in DoItYourself, I am able to get the Z-switch and regular switch in the garage to work now. My next question is, how do I add the z-switch to my SmartThings Hub? I clicked on Add a Thing and it’s not able to find the z-switch. What should I do next?

Follow the switch’s instructions for pairing while the hub is in pairing mode.

If that doesn’t work, follow the instructions for performing a z-wave general exclusion and try pairing again.

Thanks, guys! I got it added to the hub now.

Okay, how do I schedule the light switch to turn on and off at certain time of the day? Or, when the sun goes down and comes up?

Check out the community wiki,

Or the official support pages,

For lots of step by step instructions on setting up basic automations.

Thanks, I got it working.