Showing results for 
Search instead for 
Did you mean: 
Replies are disabled for this topic. Start a new one or visit our Help Center.

I replaced a nest 3rd generation stainless steel ring with a new 3rd generation

Community Member

Using the old base, I replaced a nest 3rd generation stainless steel ring with a new 3rd generation stainless steel ring. The setup on the new ring proceeded fine, but would not complete the tests for a/c and heating. I received no error message but the a/c and the heating would not operate.  I check the thermostat using the nest app on my iPhone and had message on the app saying a wire on the base plate was wrong. I had not disturbed the base or the wiring. The old ring had worked fine for the past 4 years. I don’t understand why the new ring has a problem with the wiring, when the old ring did not. Any help you could provide would be appreciated.


Community Specialist
Community Specialist

Hi clearwater,


Thanks for reaching out. I'm sorry for the delay. Your thermostat's old base, may not be compatible with its new display even if they're both Nest Learning Thermostat 3rd Gen. Try to power cycle the thermostat power breaker.  Also, restart your thermostat by going to the Settings > Reset > Restart.


If the issue persists, follow this guide:


  1. Take a photo of your current thermostat's wiring.
  2. Turn off your breaker, as you have to disconnect all the wires from your thermostat's terminal.
  3. Ensure that all the wires are properly stripped and straight.
  4. Reconnect the wires to its assigned terminals.
  5. Turn the breaker back on.


Let me know how it goes.