2nd Gen Sensor can't "see" my new 4th Gen thermostat

[skjwood]

I had a 3rd Gen thermostat and a single sensor connected to it. Everything was fine. Then decided to get a 4th Gen thermostat so I could add more than one sensor. Installed the new thermostat with no issues, and it appears in the Google Home app and controls my HVAC as expected.

When I tried to add my existing 2nd gen sensor to it, I got an error saying I need to install a compatible thermostat. I uninstalled from the Home app, pulled the battery on the sensor, left it out for 48 hours, and tried again. I restarted the thermostat at the same time I reinserted the battery. Got the same error message. Need to install a compatible thermostat. When I go to the settings of the sensor to see if I can link it that way, my thermostat doesn't appear as an option. Again, the thermostat is in the Home app and running the HVAC.

Bought a new sensor, just in case that was it. I get the same error message during setup. I'm returning it. 

Bluetooth is on my phone when trying to connect. Thermostat connects to wifi. Can change the wifi, so I believe Bluetooth is working on the thermostat. 

Any ideas? I've tried every solution I could find in the community. Ready to switch to ecobee. 

[skjwood · Accepted solution]

Figured it out. I don't have the Nest "Learning" Thermostat, so sensors can't be used. Did not realize that when purchased. Returning for the Learning thermostat. 

[jenniffert]

Hi skjwood,

Thanks for reaching out here in the community! I understand you had trouble connecting your Nest Temperature Sensor (2nd gen) to your thermostat due to an erroneous model. I'm glad you pinpointed the reason for the error, and I appreciate the update.

For details on the Nest Temperature Sensor, including compatibility and setup after installing your Nest Learning Thermostat, please refer to this article: Learn about the Nest Temperature Sensor.

Let me know if you have questions or concerns. 

Best regards,

Jenniffer