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

Trying to get a replacement Nest vs 3 as existing as died

Community Member

My Nest Learning Thermostat has died and is no longer in warranty.  I'm hoping that I can get some advice and support from Google as I hate throwing away a $300 plus item and questioning the long-term quality of Google's product. 

 I purchased my Nest Learning Thermostat over 3 years ago.  never an issue.  I recently did some renos and when the nest was reinstalled, the system reported the E74 error issue with no power to Rh.  I have since had HVAC gome through and confirmed furnace is working and the wiring is good.  Tried a different back plate and still the same issue.  Replced with a temp thermostat and that also works. 

The issue is thought to be now a programming issue inside the Nest unit.   This should not happen with a google device of this calibre or cost and so I'm hopeful a good-will replacement could be sent out to accommodate my situation.  


Community Specialist
Community Specialist

Hello rsutton7672,

I appreciate you posting here in the Google Nest Community in terms of getting a resolution by replacing your Nest Thermostat that is no longer getting any power. I'd be happy to check its eligibility for you.

First off, can you share with us the power readings on your thermostat's Technical Info option? A proper reading would help us identify if it was a wiring or a terminal issue. Also, does it have a C wire?

Keep me posted.


Not sure I understand fully, but the Tech Info diagram showed could not pick up the red wire being connected to the RH terminal on the back plate.  It stated no power however the HVAC and mutli tested showed that there was power in the line.  I do have a common wire which at the time was connected to the C terminal on the nest wiring backplate.  The Nest did recognize this connection.    Strangely, when the common was connected to the NEST without the RH wire, the nest would not recognize this wire being connected which it should have.  The conclusion at this stage is that the programming inside the Nest unit is malfunctioning at this stage which is disappointing.  The unit serial is ######  with another set of id numbers below the QR code that read ######



“For the safety of our community members, this post was edited to remove personally identifiable information.”

Hey there,


I'm sorry for the confusion. If your Nest Thermostat is still currently installed, you can gather its power readings in the Technical Info settings, or if the wiring report appeared on the screen, a Technical Info option would show. Click on it and select Power. You should see the battery level, Voc, Vin, and LIn.

Also, can you try removing the C wire, leaving it disconnected, and leaving the other wires inserted? Then, tap and hold your thermostat screen for 10 seconds until it shuts down to refresh to see if it will make a difference.

Let me know how it goes.