Nest Learning Thermostat, 3rd gen disconnected from WIFI (low batter)

[gpbob]

Hi, I have a 3rd gen thermostat that is about two years old. This morning I found that it was offline (our remote temperature sensor also shows offline) in the IOS app. I've gone through the trouble shoot process and found the following power indications:

Battery: 3.678V

Voc: 37.92

Vin: 28.86

Iin: 20mA

We've not had any power outages recently. I cannot get the thermostat to reconnect to wifi so I'm assuming the battery has dropped below 3.6V at some point and disconnected. Is it possible that the Lithium battery could require replacement after only two years of use? Is it also normal for the remote sensor to also say offline if the base unit battery is low? Any other tips to get this thermostat back online?

Thanks, 

gpbob

[gpbob]

I should add, on the "Network" page on the thermostat is says "Not Connected" and below that "Low battery." and on the "Lock" page is also indicates "Low battery."

[zoeuvre]

Hi gpbob, 

Uh-oh! Let me take a look at this for you. A few questions: 

1. Are you located in North America or Europe?
2. When did the issue first occur?
3. Are the power breakers on, and do you receive power to your home?
4. Is the thermostat's display seated properly?
5. Are all the wires of your thermostat seated firmly in its terminals (with no loose or exposed wires)?
6. Have you tried to charge the thermostat display already using a micro-USB cable? If not yet, charge the thermostat using a micro-USB cable and a USB charger and  plug the thermostat’s display into a power outlet and leave it plugged in for ten minutes. If still low battery, charge it again for an hour. 

Let us know how it goes.

Best,

Zoe

[gpbob]

I seem to have solved the problem by disconnecting and fully charging with the USB cable. Since then the battery seems to be staying over 3.8V at all times (I check it from the Nest App / Technical Info). I don't understand why it would have dropped below 3.6V unless there was some type of firmware update / glitch? The thermostat is wired properly and we've not experienced any power outages so there's no good explanation for why it dropped so low and disconnected WIFI. Anyway, hopefully it was a one-off and all will be good now. While I have your ear, I must say that the whole Nest / Google home ecosystem is quite a mess in regards to having one UI that is dependable and works across all the legacy Nest and Google hardware. I'm heavily invested in the ecosystem and would expect a better experience by now. Hopefully the work continues to properly integrate all the pieces into one dependable UI. Maybe you can relay my feedback up the food chain. Thanks so much for the reply!

[gpbob]

Sorry, forgot to answer your first question, I'm in North America ...

[zoeuvre]

Hi there, 

Awesome! I'm glad to hear that you were able to resolve the issue with your Nest Thermostat by disconnecting it and fully charging it with the USB cable. It's possible that the low battery voltage was causing the power and Wi-Fi connectivity problems you experienced. Regarding the drop in battery voltage, firmware updates or glitches are indeed one possibility, as updates can sometimes affect power management or connectivity. It's also worth noting that battery performance can be influenced by various factors, such as environmental conditions or the age of the battery itself.

Thank you also for sharing your feedback, and I hope that your Nest Thermostat continues to work smoothly moving forward. If you come across other information you'd like to pass along or have more questions, feel free to create a new post.

Regards,

Zoe