Nest Gen 3

[AW3]

I installed 2 Nest Gen 2 thermostats several years ago for 2 zones with heating and air conditioning. Both worked perfectly. I upgraded both to Gen 3 thermostats. One works perfect and the other continuously cycles on and off, chattering at the control panel. Checked the wiring multiple times. Connected a Nest power connector C wire substitute. Nothing worked. Reinstalled the Gen 2 thermostat in this zone and it works perfect. 

[Jeran]

Hey there AW3,

I'm sorry to hear one of your Nest Learning Thermostats is acting strangely! I can imagine this issue would make you pretty nervous, so I'd be happy to help out. Let me just ask you some questions about what's happening:

• Do you get any kind of error message on the Thermostat?
• Have you tried swapping out the working 3rd Gen Thermostat with the one that's acting strangely?
• Would you be able to post a picture of your old wiring with the 2 Gen Thermostat?
• Have you checked the power readouts on the 3rd Gen Thermostat?

In case you haven't already seen this article, go ahead and follow the troubleshooting steps.

I look forward to your response, and if you have any other questions or concerns for me, please let me know!

Best regards,
Jeran
 

[AW3]

Hi Jeran,

This is what I tried:

I thought it might be a defective thermostat.  Google replaced it with a reconditioned one.  Still did not work.

I checked the wiring on the Gen 3 thermostat (Entryway) that is working, the same as it always did with Gen 2, and did exactly the same on the Gen 3 (Master Bedroom) that was not working.  Still did not work.

I took the Entry Gen 3 thermostat that is working and installed it where the Master Bedroom Gen 3 was not working.  Still did not work.

I reinstalled the Gen 2 where the Master Bedroom Gen 3 does not work, it works as it always did.

Attached is a photo of the wiring where the Gen 2 works and the Master Bedroom Gen 3 does not.  This is exactly the same as the wiring for the Entryway Gen 3 that does work.
The Master Bedroom Gen 3 thermostat when installed clicks at the control panel and continuously tries to cycle on and off.
The Gen 2 thermostats worked fine for years.
The Entryway Gen 3 thermostat works fine with the same wiring setup as the Gen 2.

 

[Jeran]

Hey there AW3,

I apologize about the delayed response, I appreciate your patience! It's interesting that both the 3rd generation Learning Thermostats are behaving strangely, while the other thermostats work fine. In this case, I think talking with Nest Support may be best, since they may be able to check the internals of the Thermostat and see if the device is not communicating with your HVAC system properly. If you don't mind, would you be able to fill out this form? Afterwards, someone from Nest Support will get into contact with you.

I look forward to your response as usual!

Best regards,

Jeran

[Ryan_G]

Hey everyone,

I'd like to jump in here and check if you've seen Jeran's response. Let us know if you need more help by replying to this thread.

Thank you for your help, Jeran.

Regards,
Ryan 
 

[AW3]

I completed and submitted the form as requested.

[Ryan_G]

Hey AW3,

Thanks for the reply.

It looks like a case has been created and one of our colleague is already working with you on that. 

Let us know if you need anything.

Regards,

Ryan

[EdwardT]

Hey AW3,

I wanted to follow up and see if you are still in need of any help. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further.

Thanks,

Edward

[EdwardT]

Hi AW3,

I'm just checking in to make sure that you've seen our response. Please let us know if you have any other questions or concerns as I will be locking this in 24 hours.

Thanks,

Edward

[AW3]

I am being helped from two Google Nest specialists. We are communicating by email and phone working to resolve the problem. Thanks. 

[MelbaDT]

Hey there, 

Glad to hear that you're already working with a specialist about this — please continue there. Also, we'll go ahead and lock this thread after 24 hours. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the Community.

Best, 

Melba