Nest Thermostat Low Battery (5 Easy Methods to Fix it)

Nest Thermostat low Battery

You don’t know how to fix a Nest Thermostat low battery issue? Luckily, you’ve reached the right place!

Several users have complained of this constant error message, so we will evaluate this case and provide you with proven methods to solve it.

The Nest thermostat may display low battery error messages if its Battery is low or there is a power outage. It is also possible for the Battery not to be recognized due to hardware or software problems. Maybe your charger isn’t working, or your Battery has gone bad.

Quick Fix:
How to fix the Nest thermostat’s low battery or not charging? If your Nest thermostat battery is low, try charging the inbuilt battery. If a C-type wire adapter powers the thermostat, you can also troubleshoot its wire connection to the HVAC system. 

No matter the reason, we’ll eliminate each possibility one by one until the real reason emerges. Our next step is to find out where the issue might be coming from, so we have prepaid that first.

Table of Contents

How Does The Nest Thermostat Battery Work?

The Nest thermostat is powered by a lithium polymer battery with 380 mAh. The Nest thermostat battery is charged by drawing power directly from the HVAC system.

The battery keeps the thermostat running during power outages or when the HVAC unit does not have power. Nest Thermostats also come with Wi-Fi activity sensors and backlit displays.

How Long Does Nest Thermostat Battery Last?

The Nest thermostat not working on a freezing cold night is going to be a nightmare. Thanks to Nest, all edge cases are covered.
The Nest thermostat is not battery-powered but has a lithium-ion battery that acts as a backup when the power goes out.
This means it will operate for approximately two to three hours before it completely shuts down without power. It is important to note that when a battery powers the device, you cannot access all the smart features it offers.
The Nest thermostat automatically turns off Wi-fi connectivity to provide basic cooling and heating functions, meaning that all smart features have not been used.

Nest Thermostat low Battery:

Some users have complained that their thermostat constantly displays low battery messages or does not work. We gathered all possible causes for the Nest Thermostat’s low battery issue.

1. The Nest thermostat is uncharged:

The Nest Thermostat low battery issue may occur when your thermostat has not been charged. You are connecting it to another wall outlet and avoiding using any power splitters between them.

2. The charging cable is faulty:

If your Nest thermostat USB charging cable is not working, the thermostat won’t be able to receive any electricity at all. You can test the cable on other devices to determine whether it works.

3. Charging port not working:

The charging port on Nest might be faulty if it doesn’t charge when plugged into the power source. There is no way to tell if the slot is faulty, but you can try a different charger.

4. Battery problem:

The thermostat will constantly display low battery error messages if its Battery is faulty, even when fully charged. If your thermostat’s Battery is faulty, you can only replace it.

5. A temporary problem:

In this case, you would be lucky. You can sometimes solve the problem by taking the Battery out and re-inserting it.

6. Hardware/software problems:

The internal Battery of the thermostat may have been damaged if it has been somehow damaged. The thermostat might have a software bug preventing the Battery from charging.

After you’ve identified the possible causes, we can move on to the troubleshooting part of this post and resolve your issue as soon as possible!

Nest Thermostat Low Battery Issue: How To Fix It?

Some of our methods will involve entering the Nest mobile application and modifying Nest’s settings, so we assume you already have the Nest hooked up to the Nest App.

So, how do you fix your Nest thermostat low battery issue?

When your Nest thermostat displays a low battery warning, you need to charge the Nest thermostat battery. Other easy methods include checking your thermostat’s wiring for damage and using a C-wire adapter to solve the Nest thermostat low battery issue.

Following this, let’s look at how to fix your Nest thermostat low battery problem.

Method #01: Charge your Nest thermostat:

Nest Thermostat Low Battery Issue

The most basic and straightforward thing you can try before undertaking any drastic troubleshooting is charging your Nest thermostat.

You could have left the charger unplugged, which results in those constant Nest Thermostat low battery messages you’re annoyed by.

Charge your thermostat for a few hours by plugging it into the charger. It is recommended to use a wall outlet with a USB cable that also works.

See if that helps, and if you’re still getting low battery issues with your thermostat, proceed with our next method.

Method #02: Power cycle the Nest thermostat:

You can power cycle your Nest thermostat now that you’ve tried to charge it, but it didn’t work. A universal troubleshooting workaround that helps in every case is altering the power. Press the thermostat ring for up to 10 seconds to power cycle your Nest thermostat.

The next step is to remove the batteries from the device and unplug all the cables. Put everything aside and wait for 2-3 minutes.

Start the device after reconnecting all the cables. After draining all electricity from your thermostat, it should be rebooted.

Hopefully, your Battery will charge, and you’ll not see the Nest Thermostat low battery message.

Method #03: Check the Charging Cable:

Nest Thermostat Low Battery charging cable Issue

If you still have Nest thermostat low battery error messages, you can try charging Nest with a different charging cable. Get another USB cable and plug your device into a power source.

Cables are known to malfunction after a while of usage, so having another cable will make things easier.

Method #04: Install a C-wire:

If you face a Nest Thermostat low battery issue and regular charging doesn’t work for you, install a C wire (common wire). For this problem, we have provided some steps to follow.

  1. Turn off your Nest thermostat.
  2. Remove the Nest from the base unit.
  3. Locate the common connector and note the wire’s color.
  4. Ensure the same-colored wire is connected to the Nest C connector.
  5. You should run some wire between the thermostat and your furnace if there isn’t a cable.
  6. After starting a fire, refit the Nest into the base unit and test.

As long as your Nest manages to charge on its own, you shouldn’t have any problems with its Battery!

Method #05: Factory Reset Nest thermostat:

The last thing we will discuss about the Nest Thermostat low battery issue is how to factory reset your Nest!

Note: The factory reset will erase all configurations and options made until this moment.

Nest configurations are essential, and factory reset erases them, so pay close attention.

In order to set up their Nest thermostats in the future, many users photograph or take notes on their current configurations.

To factory reset your Nest, follow these steps:

  1. Tap on Nest, and you will see the Quick View menu.
  2. Click on the Settings icon.
  3. Press the reset label once after turning the ring.
  4. Turn the ring once on to all settings and click again to select.
  5. Confirm that you want to proceed.
  6. The next page will ask you to confirm the factory reset.

Now, your thermostat will reboot, and all data will be reset to factory defaults.

With luck, your Battery will finally be recognized and successfully charged.

You can fix the Nest thermostat’s low battery message by adjusting and resetting its power supply. You can always install the C-wire and bypass the Battery completely if you need a quick turnaround.


Now that you understand why the Nest thermostat low battery issue displays, you can fully deal with the Nest Thermostat low battery issue by yourself. Nest’s thermostat battery is essential since it keeps the unit working correctly and powers it. Low battery levels indicate that the Battery cannot hold a charge or is not charging. 

To get the Battery to work again and the thermostat to function normally, you need to identify and fix the problem. You can always seek external assistance from Nest support if you find it challenging or does not work at some point.

Frequently Asked Questions(FAQS)

•       When my Nest thermostat says Low Battery, is that normal?

You should be concerned when your Nest thermostat displays “low battery.” Nest thermostats are directly connected to your HVAC system. So, it should continue charging. 

•       How can I check my Nest thermostat battery level?

To check the Nest thermostat battery level, go to the Quick View Menu ➜ Settings➜ Technical Info➜ Power.

Now, look for the battery number. You can see the battery level in Volts.

•       What type of Battery does the Nest thermostat use?

Your HVAC system powers your thermostats. However, it is powered by 2 AAA alkaline batteries as a backup.

•       Is there a battery in the Nest E thermostat?

Yes, it has a rechargeable Lithium-ion battery that can be used in the Nest thermostat as a backup power source.

•       What does it mean when my Nest thermostat says “in 2 hours”?

A Nest thermostat that says “in 2 hours” means your home will be cooled in that time. 

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