The dumb switch works fine – toggling turns the light on and off, regardless of whether the smart switch has turned it on or off first. When I turn it on/off, I do not hear the relay click on the smart switch.
If the dumb switch is in a position where the light is on, then the smart switch will work fine – light goes on and off, LEDs work properly, etc.
If the dumb switch is in the other position where it turns the light off, then the smart switch is all kinds of wacky. I can turn the light on by tapping up; but then the LED on the switch turns right back off (and in Home Assistant it shows the light as off) and the light dims a bit. To turn the light off again, tapping down does nothing, but tapping up again will turn it off. I hear the relay click when tapping up both in both cases.
I noticed that when I turn the light on from the smart switch, it’s dimmer than normal. If I turn on the light from the dumb switch, it’s on full brightness; but I also notice the light dim a bit when voltage testing on the traveler line (on the dumb or smart switch).
I’m using VZW31-SN Red Series on firmware version 1.2
I’m nearly 100% sure line and load are correct. I had my electrician here and they tested the wires and they also couldn’t figure any of this out. The only thing I’m not positive on is the wiring at the light. They’re replacing that light today or tomorrow so they’ll check the wiring to see if something is strange up there.
I’ve tested two different Inovelli red switches, so I don’t think it’s a problem there, but I have a few others I could test if needed.
This is the smart switch. Line is the black wire that’s connected to the other black and red. Load is the white wire that’s connected with the yellow nut and the other white wire goes to the dumb switch. Red is the dumb switch wire, neutrals all connected. The nut with the two black wires is connecting the load wire to the light and the black wire to the dumb switch.
The electrician came back today and looked and still isn’t sure what’s going on. But now the behavior is different, though no wires were changed and I didn’t change the configuration via Home Assistnant.
With the dumb switch in position A, the smart switch works properly - tap up and light goes on and tap down the light goes off.
With the dumb switch in the other position B, the smart switch gets inverted. To turn the light on I have to tap down and to turn it off I have to tap up. The LEDs on the smart switch match the light being on or off…it’s just that the taps are backwards. Flipping the dumb switch reverts to the correct behavior.
You’re going to have to do better with the pictures:
In the dumb switch box, post so that we can see the connections to the switch. I can’t tell which terminals the conductors are on. Also, pull that switch out and take a picture into the box. I’m guessing all 3 conductors on the dumb switch are from the same 3-wire, but I’d like to see that to confirm.
In Inovelli box, pull those conductors out. We have to be able to look into the box and trace each conductor. For this, we should be able to see the 2-wire to the load and the 3 wire, and all of their connections.
Just a side note and probably unrelated. I see in the dumb switch box that you have an Inovelli. Strange since that’s not a “neutral” box (unless you are running two Inovelli’s in a 3-way).
I can’t trace the 3-wire in the Inovelli box. Go into that box and trace the black from the 3-wire. It should be connected to the black of a 2-wire (presumably going to the load). That 2-wire’s white should be connected to a neutral bundle. You’ll have to confirm that.
What is the load? Depending on the load, if the wiring is correct, this could be a signalling issue which sometimes happens with dumb switches. I understand that you’re swapping the light. Any different behavior after the swap, or is that the different behavior you were referring to previously.
Hi @Bry - the wires are short so I can’t pull much more out. But I can confirm that the black from the 3-wire (that goes to the dumb switch) is connected to the black of the 2-wire (that goes to the light). The white from the 2-wire is connected to the neutral bundle.
The load is a ceiling light, previously with four candelabra lights (non-led). The new light fixture has 5 LED bulbs.
After changing the light fixture, the behavior is the same as I mentioned in my most recent post.
Yep, triple checked it (also tried setting it to single pole and back again to make sure it was set). I’ve also factory reset the switch a few times (pull the air gap, push it in, hold down the paddle and config button til it turns red, set to 3-way directly in the switch with the bottom paddle + config 5 times).
Is it worth trying another inovelli switch to see if that’s the problem?
I recently had an issue with dumb switches when the length of wire between them is long and there are multiple loads. It’s a known problem. Fortunately it was not an issue, since it was only temporary until my aux switches arrived.
I installed a blue series and tried to pair with Z2M in home assistant, but it’s failing with these errors:
2025-09-21 13:48:37zh:controller: Interview failed for '0x8c8b48fffe4c5e43 with error 'Error: AREQ - ZDO - simpleDescRsp after 10000ms'
2025-09-21 13:48:37z2m: Failed to interview '0x8c8b48fffe4c5e43', device has not successfully been paired
2025-09-21 13:49:13zh:controller: Interview failed for '0x8c8b48fffe4c5e43 with error 'Error: AREQ - ZDO - simpleDescRsp after 10000ms'
2025-09-21 13:49:13z2m: Failed to interview '0x8c8b48fffe4c5e43', device has not successfully been paired
2025-09-21 13:49:44zh:controller: Interview failed for '0x8c8b48fffe4c5e43 with error 'Error: Interview failed because can not get active endpoints ('0x8c8b48fffe4c5e43')'
2025-09-21 13:49:44z2m: Failed to interview '0x8c8b48fffe4c5e43', device has not successfully been paired
