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.
