can't add gen 1 temperature sensor to gen 4 thermostat

glenn_k — Mon, 25 Aug 2025 23:57:08 GMT

I have the gen 4 thermostat, which is working fine, and I'm trying to add the gen 1 temperature sensor. The instructions say that the older temperature sensors will work, but when I do the installation I get the message "Add a compatible thermostat" If I then exit the setup, which is my only option, I find that the sensor shows that it's offline. I've tried multiple sensors (I've got a pack of 3). I've tried resetting and factory resetting the Thermostat. I've tried resetting the sensors by removing their batteries for 5 minutes. I've tried this with the Google Home app under both Android and iOS, but they have the same issue. I've seen a couple of messages in the forums with other people having the same issue, but I don't see a solution.

Are they incompatible? I'm in the USA if that makes a difference.

Re: can't add gen 1 temperature sensor to gen 4 thermostat

glenn_k — Mon, 08 Sep 2025 01:26:03 GMT

So now I've found that the issue is not the gen 1 temperature sensor because I just bought the gen 2 temperature sensors and they have the same issue with my gen 4 thermostat; instead of connecting to the sensor, it says "Add a compatible thermostat". I've once again tried resetting and factory resetting the Thermostat and resetting the sensors and nothing seems to work. What can be the issue?

The info about the thermostat from the Home app:

Model: Thermostat-1.4

Device ID: 641666006471179C

Serial no: 52211J3DB4O8M4

Software version: 2.2-6

Can anyone help?

Thanks

topic can't add gen 1 temperature sensor to gen 4 thermostat in Nest Thermostats

can't add gen 1 temperature sensor to gen 4 thermostat

Re: can't add gen 1 temperature sensor to gen 4 thermostat