Nest Learning Thermostat Wi-Fi keeps disconnecting and reconnecting from low power

[chimerical]

Hi, I have a Nest Learning Thermostat (3rd gen) that keeps going offline because the "thermostat doesn't have enough power for Wi-Fi".

Sometimes, if I leave it alone for a day, it corrects itself and presumably has enough power again. Other times, I unplug the thermostat from the base and charge it through USB.

I'm trying to figure out the source of the issue, since I used this thermostat in a previous home that did not have this problem.

Technical info I see when this "offline" error occurs:

• Battery: 3.631 V
• Voc: 35.85 V
• Vin: 31.91 V
• Lin: 20 mA(i)

No other devices in the home are experiencing any kind of Internet connectivity issues.

Any ideas?

[Markjosephp]

Hello chimerical,

I'm sorry to hear that you're having an issue with your thermostat that won't connect to Wi-Fi due to power issues. I'd love to help.

Most of the time, Google Nest Thermostats can use the heating and/or cooling wires to charge their internal battery. To reliably supply power to the thermostat, you might need to connect a common wire, often known as a "C wire," or the Nest Power Connector. Please have a look at this article and let us know if you need more help.

Thanks,

Mark

[Markjosephp]

Hey there,

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,

Mark

[chimerical]

Thanks, I read about the C wire and Nest Power Connector options and may have to consider those. But since it looks like I am getting enough power most of the time (but not all the time), is there something else going on that can be fixed with the current hardware setup, based on the technical info here:

Technical info I see when this "offline" error occurs:

• Battery: 3.631 V
• Voc: 35.85 V
• Vin: 31.91 V
• Lin: 20 mA(i)

The battery level goes up and down between 3.5x to 3.7x V, and I'm not sure what causes it to dip below 3.6 V sometimes.

[Markjosephp]

Hi chimerical,

Thanks for reviewing the article and observing your thermostat's behavior. Wi-Fi connection is unstable, the connection between your thermostat and your router has interference, and the thermostat may have power issues that have been overlooked for a long time. These are some of the possible causes why your thermostat won't hold its charge.

Disconnecting it from the Wi-Fi network temporarily would help your thermostat hold its charge. At this rate, the best thing to do to avoid power issues is to install a C wire. Usually, it's common for an HVAC system to have a spare wire. You might have one hooked up on its control panel that you can use.

Let me know if you have more questions.

Regards,

Mark

[chimerical]

I see, thanks for the troubleshooting tips!

[Markjosephp]

Hey there,

I'm happy to help! If there’s anything else I can help you with, please let me know.

Thanks,

Mark

[EdwardT]

Hi chimerical,

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

[chimerical]

Thanks Edward, this has been helpful for getting me started on troubleshooting the issue.

[EdwardT]

Hi chimerical,

Thanks for the update. Let us know if you have other questions and we'd be glad to assist you.

Thanks,

Edward

[AbigailF]

Hey chimerical,

Checking back in should you still have some questions here. Let us know by replying to this thread. 

Best, 
Abi

[AbigailF]

Hello chimerical,

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.

Regards,
Abi