UK - Thermostat unresponsive and randomly resetting.

[lenbewis]

I bought a house nearly five years ago with a Nest Learning Thermostat. It's a 2nd Generation Model (stats below) with a USB powered backplate and has worked flawlessly for the last five years but in the last week seems to be having lots of issues.

Spoiler

Thermostat

Model: Display-2.8

Backplate Model: Backplate-3.2

Software: 5.9.4-5

Battery: 3.59 Volts

Heat Link

Model: Amber-1.4

Software 2.1.2-1

Initially, it reset itself in the night. I went to reconnect it only to find that the outer ring control was only responding intermittently. The button (pressing the screen) did not have a problem working, so I could see that the unit wasn't frozen. Eventually I reset the whole system and reconnected to the heatlink. A day or so later- it seemed to reset itself again. It was complaining about low battery so I relocated it to another usb source. However the outer ring control is only working intermittently and the battery seems to be struggling to recharge so thus far I have been unable to reconnect it.

[Frustratedddd]

You can see the battery is low at 3.59v, you should be up above 3.75v. They usually run at about 3.83v, so you can see this might be a battery replacement job.

The 2nd Gen are pretty robust, so I would edge my bets on a replacement battery.

[lenbewis]

After an overnight plugged into a more solid power supply (the one that came with my old Google Home). The battery is now holding steady at between 3.9 and 3.95 volts. It drains very quickly when unplugged so I do suspect the battery is partly to blame.

Unfortunately the control issues are the same- the wheel controller is non responsive while the button still works. I have a replacement battery on the way so will see if there is anything else untoward inside. I've had it on other devices where the battery gets old and misshapen and that affects the working of the device.

[virnab]

Hi lenbewis,

Thank you for reaching out to our community.

I’m sorry to hear that your Nest Learning Thermostat (2nd gen) is unresponsive, randomly resetting, and is complaining about low battery. Thank you for sharing with us important details about the behavior of the Nest Learning Thermostat (2nd gen), the troubleshooting steps you have taken to resolve the inconvenience, and it also is important to know that you already are waiting for a battery replacement to check if that is the real cause of the Nest Learning Thermostat (2nd gen) behavior. No worries, help is here.

Before I start further troubleshooting, let me ask you a few questions:

1. Is there a wiring report or error message on your thermostat and/or app?
2. Do you see a blinking LED light? If so, is it red or green?
3. Has there been any recent work done on your thermostat(s) or heating system?
4. Were there any power outages?
5. Were there any modifications to the internet configuration (for example, added extenders)?
6. What are the power readings? To check this information, please go to your Nest Learning Thermostat (2nd gen), then select “Settings,” then “Technical Info,” and then select “Power.”
7. Is the thermostat display responsive when interacting with it?

Thanks for your kind attention; I will be looking forward to your answer.

Best regards,

Virna

[lenbewis]

1,2,3,4,5 are all Nos.

6. I can't currently. In the app I can see battery is at 3.89v which actually seems high. When it was working- I did a check for updates and it did not detect any. I will see if I can grab further data next time the dial is responsive.

7. Intermittently. The button press always works, the dial often doesn't. Currently it is randomly assigning the temperature to 21 degrees at various points during the day but it still talks to the app so I can override it. We have 0 degree temperatures at the moment so I am just working with it as it is until milder weather.

[virnab]

Hi lenbewis,

Thank you for your timely response and the comprehensive information you've provided.

We continue working for you, looking for the solution.

My team would like to know more about this behavior. When you get a chance, please fill out this form. Remember to include the link to this post. Let me know when you’re finished. From there, we'll contact you via email.

Your confirmation is crucial to ensuring that I can follow up on your case effectively.

Best regards,

Virna

[lenbewis]

So I was able to change the battery as recommended which did not change the behaviour at all. I bought a second hand replacement thermostat unit (nest 2nd generation learning thermostat) but was unable to connect that either so that is going back.

My nest is currently uninstalled and replaced with a more traditional thermostat, and if I can't find a fix I won't be going back to nest.

[virnab]

Hi lenbewis,

Thanks for keeping me in the loop about the steps you have taken to restore your thermostat.

We haven't seen your submission form come through yet. Were you able to access it okay? Let us know if you're running into any trouble, and it will be my pleasure to continue assisting you.

Best regards,

Virna