topic 3RD generation showing low battery in Nest Thermostats

3RD generation showing low battery

skibum — Fri, 29 Dec 2023 16:51:31 GMT

I just moved in this house and the Nest is now showing low battery message and will not connect to the wifi which until now has been working fine.

The power readings are below

Battery 3.657v

Voc 37.42 V

Vin 29.69 V

lin 20mA (i)

I understand these batterties are not replaceable so what should I try?

Thanks

Dave

Re: 3RD generation showing low battery

grederick — Fri, 29 Dec 2023 18:52:29 GMT

Same problem here. New battery lasted less than two months. If Thermostat fails when we are gone, the furnace will not come on and we are in MN winter time

Re: 3RD generation showing low battery

Markjosephp — Fri, 05 Jan 2024 21:09:15 GMT

Hello folks,

Thank you for taking the time to let us know about your inquiry.

@skibum, welcome to your new home! It seems like you're facing an issue with your Nest Thermostat displaying a low battery message and having trouble connecting to Wi-Fi. Let's sort this out.

Based on the power readings you provided, it looks like the battery voltage is at 3.657 volts, which already indicates a problem with the power. Does it have a C wire installed? Can you check for any available wire you can use as a C wire? Also, here's an article to learn about the common or C wire.

@grederick, I'm sorry to hear you're also facing the same issue. Can you share with us your thermostat's power readings as well? Also, does it have C wire installed and are you seeing any wiring reports?

Keep me posted.

Best regards,
Mark