Very low battery / replace now

[BrKorb]

I ran the thermostat for 8 months and it behaved normally. Then, I got this message, so I replaced the batteries. A few days later, I got the same message. This time, I decided I'd let it fail, just to see how long it would take. It's been two months now. It's still working and still complaining about the battery being very low. And, yes, the "C" wire is still showing 18V. This seems to be a common problem. Why?

[Markjosephp]

Hello BrKorb,

I'm sorry to hear that you're having an issue with your Nest Thermostat because it's not holding its power. I'd be happy to take a look into this for you.

It's most likely that your system may not provide enough power or any power to either the thermostat or a specific wire, so your thermostat can't complete a circuit. Please check the "Power Info" on your thermostat's equipment settings and check for any wiring report under "Wiring Info." Also, could you please share with us a photo of your thermostat's wiring?

I'll look forward to your response.

Thanks,

Mark

[BrKorb]

It says the voltage is 38, which seems a little high. It *IS* wired to the "C" terminal on my FAU. It is a Trane XR90 propane heater.

[Markjosephp]

Hi there,

Thanks for sharing the pictures with your thermostat's diagram and power status. Let's sort this out.

Have there been numerous power outages while you've been using it? The batteries in the thermostat will keep it running in the event of a power outage. The battery life is shortened when it only receives power from the batteries and not from any of the power wires.

Please check the battery health in its settings. If the battery health is higher than 1500 milliohms, remove the batteries and clean the contacts. Then, check if there are changes. If the readouts are still the same, replacing the batteries would be the best option. Have a look at this article and let us know if you need more help.

Regards,

Mark

[BrKorb]

I have Tesla battery backup. Power outages last way less than one second. Some clocks will reset, but most of the electronic clocks maintain the time correctly. So, anyway, there were a few, but none longer than a fraction of a second. I take it, then, that 38V is not a problem. BTW, it runs completely fine. The entire issue is the persistent message that the battery is low and that indication started *WITHIN TWO DAYS* of installing new batteries.

P.S. that link wasn't to an article, it was to a guided self-help telling me how to install batteries. It also taught me that "Google Nest" refers to a whole line of products, not just thermostats. Great. Anyway, you should be guessing by now that I do know how to ensure that batteries are installed correctly and make contacts. 

BTW, I do have a Klein Volt/Ohm meter, but I do not know how to test the resistance across a battery. They tend to push electrons, making resistance to flow difficult to measure. Are you talking about milli amp/hrs of charge?

[BrKorb]

Ping, Google Nest Person

@Markjosephp 

[Markjosephp]

Hi BrKorb,

I'm sorry for the late reply, and thanks for letting me know more. How's it going with your thermostat? Are you still getting a "Low battery" message? Please let me know so I can look for more options.

Regards,

Mark

[BrKorb]

THERE HAS BEEN NO CHANGE.

[Markjosephp]

Hello BrKorb,

I'm sorry to hear the issue still persists. We'd like to take a further look into this for you.

Please fill out this form with the needed information so we can investigate it, and let me know once you're done.

Regards,

Mark

[BrKorb]

I already filled out that form. Is it necessary to do it a second time?

[Markjosephp]

Hi BrKorb,

I see that you have a similar post in another thread. No worries! We have received it. Soon, a member of our upper team will contact you via email. Also, please continue the conversation there, as this thread will be locked within 24 hours.

Thanks,

Mark

[BrKorb]

Since this is the main thread of my problem, I think this should stay open until I can publish a "fixed now" message. People who stumble into it would be able to see how long resolutions might take.

[Markjosephp]

Hello there,

Thank you for your patience with us, @BrKorb. I'll keep the thread open until you get assistance. Also, I'll send a follow-up to the team, so please be on the lookout for an email from us in your inbox soon.

Thanks,

Mark

[BrKorb]

Nest Thermostat Back

[Markjosephp]

Hi BrKorb,

Thanks for posting your thermostat's backside. Your new thermostat is currently being processed by our team. It appears that we can now mark this one as finished, and I will lock the post in the next 24 hours unless I can be of more assistance.

Best regards,

Mark