I recently noticed the new Unify Thread Network option for the SmartThings hub and decided to try it out and see if I could join my hub to my Google Home Thread network. However, when I go to unify it, the option to “Join this hub to another service’s Thread network” is greyed out with the text “Only hubs without connected devices are supported”.
I did have a few Matter WiFi bulbs connected, so I removed them and tried again but got the same result. Currently, I only have some ZigBee devices and a Z-Wave device connected. Do I have to remove those as well? It doesn’t really make sense that completely unrelated protocols would interfere with switching which Thread network the hub is using.
One of my V3 hubs does the same thing (the others don’t even report the thread network in the app at the moment).
I agree that Z-Wave devices shouldn’t make a difference but Zigbee and Thread use the same radio channel on the V3 so if you join another Thread network that uses a different channel you will also be changing your Zigbee channel whether you want to or not (it might look as if you can change one without affecting the other but it only looks like that). So I guess they are trying to save users from themselves.
I was finally able to join my Smartthings hub to my unified Google thread network.
I reset the ST hub. After setup and before adding any devices, I selected “join another thread network” under the “manage thread network” setting. It displayed both my Nest Hub and Google TV Streamer 4k thread networks. I selected the Google TV Streamer 4k which was listed as the preferred thread network.
It took about 5 minutes to complete the process. Now my ST hub is connected to my unified thread network.
