Nest thermostat with power connector still eats batteries

[Georgerb]

I have my next thermostats wired correctly. I have the power connector wired correctly. All tests show normal and fine in configuration menus. It still goes through new batteries about every 2-3 weeks. Even rechargeable ones which I thought the power connector would charge for me. That may just be rumor on the net. Please advise. I like the thermostat but don't want to feed it batteries all the time. -George

[jeffman]

I've been having the exact same problem. It was working 100% fine for the past year, but about a month ago I started getting battery warnings and I've been needing to replace them every ~2 weeks ever since. Nothing has changed anywhere in my system and all of the wiring is fine.

[TB51]

I have been getting the same message, and trying to find an answer for a couple months, because I have a battery tester that says they are fine, full of power.   Something triggers a change in the way the thermostat reads/reacts to the batteries.  There does not seem to be an answer available here on the boards.

[Georgerb]

Thanks for the replies. If I could just ignore it, fine, but it eventually goes offline until new batteries are put it so I don't think their levels are up. I think they just get drained. It's not using the power from the power connector although it shows fine in the menu. Any other ideas besides replace it?

[Patrick_Caezza]

How do you have the Nest thermostat and power connector wired?

What type of system do you have? Heat/cool, heat only, boiler?

You can not use rechargeable batteries in the Google Nest Thermostat as they supply a lower voltage than alkaline batteries.

[Georgerb]

Heat only, gas furnace. All connections verified and shown to be correct in image below. Do you see anything out of place. I see enough folks online having the same issue there seems to be a systemic issue.

[Georgerb]

Anything look out of place?

[Markjosephp]

Hello folks,

I'm sorry to hear you're all having the same issues with your Nest Thermostat. But I wanted to stop by and see how I could help.

@Georgerb, could you please try resetting your thermostat to its default settings? This will remove your account information and might help us clear the low battery prompt. Here's your guide on how to reset and set up your thermostat. Keep me posted if that helps.

@jeffman and @TB51, a few questions: does it also have a C wire connected or a Nest Power Connector installed? Could you please share with us the power readouts on your thermostat? Also, please try to reset it as well and let us know if it works. I'll look forward to your response.

Thanks for the help here, @Patrick_Caezza.

Regards,

Mark

[jeffman]

Thanks Mark -- here are my power readouts:

Vin: 33.120 V, Iin: 385, PS: Y-385, YP-25

I use the Power Connector, no C wire. The wiring info says I'm connected to Y(P)-W-G-R, and it also detects the power connector ("Nest Power Connector Detected").

I've already tried a reset but I didn't see an improvement unfortunately.

[Georgerb]

Mark, I already answered your questions above along with images. This is happening to many people in a consistent way. 

George

BTW: Are you a bot?

[jeffman]

From this support page https://support.google.com/googlenest/answer/9241211?hl=en-CA#zippy=%2Cpower, typical Iin with no C wire is 20-40, but mine is 385. Ten times higher than it should be. Why is it drawing so much current, and does this explain the high battery drain?

[Georgerb]

Jeff, mine is 385 as well. You may be onto something with current draw. Seems support should be able to guide us here. 

[Markjosephp]

Hi there,

Thanks for the details, and I understand your thoughts about your Nest Thermostat's battery being drained even with a C-wire or a Nest Power Connector installed, but I'd love to know more about this.

Could you please check your thermostat's battery health?

• Go to your actual thermostat's settings and then battery status.
  • If impedance is lower than 1500 milliohms, the batteries are in good condition. But if the impedance is higher than 1500, the batteries will need to be replaced. To ensure this, please use the suggested replacement batteries with AAA 1.5 V alkaline batteries, such as the Energizer AAA 1.5 V Alkaline Battery.

Keep me posted.

Regards,

Mark

[jeffman]

Thanks Mark. The impedance is 1279 mOhm. Not quite 1500 but I will try that brand next time I replace these regardless.

As an aside, would using a C wire instead of the power connector have any advantage in this situation, or would it still be subject to the same conditions, e.g. would it need to target <1500 mOhm with a C wire?

[Markjosephp]

Hello jeffman,

I appreciate you checking it. Technically, both the Nest Power Connector and Common Wire have the same function: to deliver constant power to your thermostat and avoid power issues with your HVAC system. But they differ on how convenient the installation would be. Please take a look at this article and let us know if you need more help.

Best,

Mark

[Jenelyn_O]

Hi folks,

I wanted to follow up if you still need help. Please let me know if you’re still having any concerns or questions from here, as I would be happy to take a closer look and assist you further.

Regards,

Jenelyn

[Jenelyn_O]

Hello there,

We haven't heard from you in a while so we'll be locking this thread if there is no update within 24 hours. If you need assistance or want to discuss topics, feel free to start a new thread.

Thanks,

Jenelyn

[Georgerb]

It's still not working. Everything looks normal as shown in my images above. Just drained last pair of batteries (correct type) again. Shows LOW BATTERY, REPLACE NOW. Is it a bad thermostat? No one seems to be able to help solve this issue. Please advise.

[Markjosephp]

Hi Georgerb,

I'm sorry for the experience. We'd like to take a look at this for you.

Could you please fill out this form with the needed information? A member of our support team will be in touch over email to help.

Regards,

Mark

[EmersonB]

Hey everyone,

@Georgerb, we wanted to follow up and see if you were able to fill out the form? Let us know if you have additional questions.

I appreciate the help, Patrick_Caezza, Mark and Jenelyn.
  
Best,
Emerson

[Georgerb]

I filled out the form but it just asked me to repeat everything I said in this thread. Time now for a solution please. -George

[Markjosephp]

Hi there,

Thank you for your patience, @Georgerb. A member of our upper team will contact you via email. Also, please continue the conversation there and don't forget to check the spam or junk folder for the updates.

@TB51 and @jeffman, I wanted to ensure that everything was covered here. Please let us know if you need more help.

Best,

Mark

[Jenelyn_O]

Hi folks,

Checking if you still need help. Please let us know if you have further questions or concerns.

I appreciate your help, Mark.

Thanks,
Jenelyn

[Jenelyn_O]

Hello there,

We haven't heard from you in a while so we'll be locking this thread if there is no update within 24 hours. If you need assistance or want to discuss topics, feel free to start a new thread.

Regards,
Jenelyn