I successfully installed 2 VZM32-SN dimmers on my Hubitat C8 but then shortly afterwards I noticed my Sengled bulbs (9 in total) all stopped working in that they couldn’t be turned on or off (None of them were setup as Zigbee groupings). I thought somehow they had fallen off the Zigbee mesh. I spent hours resetting them and trying to get them to pair again. Sometimes some of them did and then worked for a while and then stopped again. I also tried to re-pair my Tuya Zigbee mmWave sensors but they kept failing to pair. They were detected but were never able to finalize with the Hubitat. Finally I air-gapped the 2 new dimmers and all the devices started to work again and I was able to pair up the Tuya mmWave sensor. Another note, I did reboot the C8 several times during all these attempted re-pairings.
One final test I did is that once everything seemed to stabilize with the air-gapped dimmers, I reenabled them and the Sengled bulbs stopped working again shortly afterwards.
Any ideas as to what might be going on here? Is there a way to temporarily disable the repeater in the dimmers?
What firmware version are you on? The recent 2.4.4.120 beta version has a very bad memory leak, and will cause your hub to simply not respond well or not respond at all. Just this morning I had to revert to 2.4.4.112.
I’m not sure where you are getting that number from the Hubitat device page. The firmware MT is 122F-0103-01030100. The software build is 01030100 and the driver date is 2025-10-03.
I believe @JohnFLand is referring to the Hub’s Platform version. The current production version is 2.4.3.177 . I’d make sure you’re on the current version.
Unless you’ve signed up for the beta program, you hub should not have the beta release he is referring to. But it’s worth double-checking.
To check the installed version, Go To Settings, Hub Details, and note the Platform Version.
Although that firmware MT doesn’t match mine, that software build # does. Plus, firmware 1.00 is all that’s out there right now (non-beta, anyway), so unless you somehow ended up with a testing / non-production device, I’m pretty sure 1.00 is what you have.
Your driver is out-of-date though – 2026-01-30 is the latest version for Hubitat. I’m still running the 2025-12-26 driver myself since it’s working fine for me.
My Hubitat is 2.4.3.177. I’ll update the Drivers. Are they generally available via the Hubitat Package Manager? I’m not getting any notice of an update.
From the HPM the version is Inovelli mmWave Dimmer Blue Series VZM32-SN v25.12.12 (driver)
Though Eric is normally impressively speedy with updating HPM, he hasn’t been updating the mmW drivers there recently. I’m sure he’ll get back to it when things chill out - he’s got a crazy full plate lately.
In the meantime, I just keep the Inovelli driver firmware GitHub pages bookmarked and regularly check those for any updates.
That answer is way out of my wheelhouse, but since I’ve seen no other reports like this here or in the Hubitat community, I suspect this may be something unique to your local environment…
Is your Hubitat’s zigbee channel selection confirmed to be deconflicted with your 2.4 wifi and any Thread network you may have? Any close neighbors that could be causing 2.4 wifi conflicts?
What is your Hubitat’s zigbee radio power setting?
What other zigbee repeaters do you have in your zigbee mesh?
There was a report recently in the Hubitat community where a user figured out that a Third Reality vibration sensor was spamming his hub with excessive message traffic when it was active, and that was knocking out some of his Sengled bulbs…
Do you have all of the various energy-reporting and whatever other reporting bell-&-whistle options enabled on your Blue mmW? If your mesh wasn’t robust (for lack of a better term) to start with, then I suppose it’s possible such message traffic from the Blue mmW could be causing a similar tipping point.
There is only my own WiFi router to compete against as my location is rather isolated. I have the Zigbee power at the highest at 16. There are other repeaters I believe but I’m not familiar on how to identify them within Hubitat. The only settings I changed on the Blue mmW was the range of movement detection - which did work great when I had the dimmer active - and changed the setting so that the movement was only reported and did not change the dimmer levels directly. I haven’t had any “severe” or “high” Zigbee reports for a while so I think my network is stable. I’m hoping the Blue mmW’s themselves aren’t loading down my network. I have 3 more to install. I only stopped at the 2 when my bulbs stopped working and I started to figure out what’s going on.
Any mains-powered device should additionally act as a repeater within its respective mesh (true for zigbee and z-wave) - the one classic exception is Sengled bulbs - they do not repeat.
Assuming you have some well-placed repeaters around, I would encourage you to try dropping your zigbee power to 8… More power is not necessarily a good thing, since that additional “loudness” blasting out makes it harder for things to be received back in to the hub.
I myself use power = 4, but I have a lot of very reliable & well-positioned repeaters in my zigbee mesh. With that lower radio power, those repeaters do all of the heavy lifting (instead of just my hub).
Heck, I’d Hubitat offered it. I’d probably drop my radio power down to 2.
Interesting. I’ve been jacking up my power thinking that would stabilize things. I will drop it to 8 first and see what happens. The other items on my Zigbee network are Sonoff window contacts, a couple of generic Zigbee 3 plugs, Third Reality motion sensors, a bunch of Tuya temperature/humidity sensors, Sonoff buttons, a 3 original SmartThings multisensors.
To check out the health of your Zigbee mesh, get the Zigbee map app, on HPM. Also lower your power to 8, like others have said. Many users report great sucess with Zigbee channel 25, what’s your channel?
And yes some Zigbee devices can wreak havoc on the mesh. Also LAN integrations can stress the hub. Do you have a C8 pro?
I’ve had Sengled bulbs, and I was not happy with their performance. They’re all been replaced with Hue(ONLY when on sale-ripoff 40.00 lightbulb) & Sylvania Zigbee
Thank you for the suggestions. I have already dropped the power to 8. Unfortunately I have to wait a couple of weeks before I’m physically back where my C8 is located. to try the other suggestions. I am too worried that if something goes wrong then my heater outlets won’t reconnect to the mesh and my water pipes wil freeze.. How well do the new ThirdReality bulbs work with Hubitat? They seem to be priced right.
A quick update. I think I have the Zigbee network stabilized. I dropped the power first to 8 (stayed on channel 20) and there was a significant improvement so then I dropped it to 4 just to try and it’s still working so I’m leaving it there for now.I also downloaded the latest driver updates from HPM and finally did a reset (exclusion/inclusion) on one of the Blue dimmers that seemed to not be reporting motion activity consistently. Since I did all this, the bulbs are turning on and off and all seems good.