Nest Thermostat Battery Won't Charge: How To Fix

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The Nest Thermostat lets you control your HVAC systems from your phone.

By using a single app, you can control the temperature settings in different rooms and get helpful insight.

Hence, it is a convenient tool that homeowners like myself can’t do without.

Unfortunately, no technology is perfect, and after a couple of years of use, my Nest Thermostat started causing a little bit of trouble.

Specifically, I noticed that my Nest Thermostat would constantly flash low battery warnings and was not charging as it should.

Luckily, I fished out some easy fixes from the sea of information online, and in the process, I learned a lot about the Nest Thermostat.

If your Nest Thermostat’s battery won’t charge, ensure that your Nest thermostat is connected to its base and that its C-Wire has not come loose.

I’ve also talked about charging your Nest Thermostat manually with the appropriate USB cable.

Why Does the Nest Thermostat Have a Battery?

All three generations of the Nest thermostat come with a built-in battery.

The battery is charged using the Rh or the Rc wires directly from your home’s HVAC system, and a common wire (C-wire) is used to complete the circuit.

With a built-in battery continuously being charged by the HVAC system, the Nest Thermostat continues to work even when the HVAC system is turned off for a long period.

The Nest Thermostat Battery might not be charging because there is no power to the Rh wire, or no power to the Rc wire.

The built-in battery is quite helpful during a power cut or during instances where there is no direct power supply to the HVAC unit.

The battery powers the Nest Thermostat’s backlit-screen, Wi-Fi card, and other special features.

Low Battery Indicator on Nest Thermostat: What Does it Mean?

When the Nest Thermostat’s battery is low, you will either see a message flash on the device’s screen indicating Low Battery or see a blinking red light.

When you spot these indicators, it is important to charge your Nest right away. You can charge it using a USB cable.

Otherwise, you will face problems with the Nest device such as:

• The Nest display screen will not work or be unresponsive.
• Your Nest device will not be able to regulate the heating or cooling function of your HVAC.
• Your Nest’s connection to your home Wi-Fi network will be disrupted.

To avoid these issues, it is best to charge your Nest manually as soon as possible and then work on troubleshooting the system.

Once your Nest is charging safely, you may want to spend some time figuring out why your Nest was unable to charge itself automatically via your HVAC system’s power supply.

Battery Life of the Average Nest Thermostat

The in-built batteries for the Nest Thermostat E and Nest Learning Thermostat could help your device run for a couple of hours to a couple of days.

Overall, its battery life depends on the type of continuous power supply the battery receives from your HVAC system.

If the in-built battery can charge itself continuously through the constant stream of power, the battery can last between 5 to 10 years.

In case the battery does not receive sufficient charge and is trained too much, some incidents suggest that the battery will start failing in two years.

The Nest Thermostat comes with replaceable AAA batteries, which can last up to two years, and in case of a power cut, can keep your device running for up to two hours.

How to Charge your Nest Thermostat Battery

Generally, your Nest Thermostat E or Nest Learning Thermostat should be able to automatically charge its battery from the power supply to the HVAC.

However, if there is an issue with the power supply to your HVAC, a power cut, or if it is simply your Nest battery being unable to charge itself, then you will need to find a way to get around the issue.

Manually charge your Nest Thermostat batteries to avoid battery problems with your Nest Thermostat. T

There are a few ways you can manually charge your Nest Thermostat batteries to help troubleshoot issues with your Nest device.

Charging the device manually should help fix your Nest Thermostat Low Battery.

Solution 1: Is Your Nest Device Connected Correctly?

Before you begin to panic about your device’s battery life running out, check whether the Nest Thermostat is connected correctly to the base.

Solution 2: Check the C-wire

The Nest Thermostat charges its in-built battery via the constant source of power to the HVAC system.

The C-wire that comes with your Nest Thermostat is used for this purpose as it helps in completing the circuit.

In some cases, the C-wire may have come loose, or it may have stopped functioning properly.

Hence, it is important to ensure that you check the C-wire thoroughly.

If dealing with the C-wire is a pain, know that you can actually install a Nest Thermostat without a C-wire

Solution 3: Charge the battery manually with a USB cable

Nest Thermostats differ greatly from generation to generation, and I’ve cataloged how the 4th gen Nest Thermostat differs from its predecessors.

When it comes to charging the battery too, there are subtle differences.

You can try to temporarily fix your battery by charging your Nest Thermostat E or Nest Learning Thermostat Battery manually using a Mini-USB for your Nest Learning Thermostat (1st Gen) or a Micro-USB cable for your Nest Thermostat E and Nest Learning Thermostat (2nd and 3rd Gen).

Solution 4: Replacing Your Thermostat Unit

When facing issues with your Nest Thermostat battery, ensure that you check whether your unit is still covered under the warranty period.

If your battery is failing and the unit is under the warranty period, you may be able to get the unit replaced.

In case your warranty period has expired, you can still talk to Google Support to understand what other options you have. You may opt to pay for a new unit or try to replace the internal battery.

Can You Replace the Nest Thermostat Battery?

Over time, wear and tear can degrade your Nest Thermostat’s battery. The battery may require more and more time to finish charging fully, and it may not be able to deliver the same performance even when it is using its full capacity.

To ensure that you get the best service from your Nest Thermostat, it is a good idea to replace the batteries.

The Nest Thermostat uses two standard 1.5 V AAA alkaline batteries, which should be replaced once you start noticing the battery’s issues.

However, keep in mind that the Nest Thermostat E and Nest Learning Thermostat batteries are in-built and not user-replaceable.

If you have these models, you will need to manually charge your Nest Thermostat battery with a USB cable.

If your Nest Thermostat is still within the warranty period, you can contact a customer support executive to explore more options.

Nest Thermostat Won’t Stay Charged

If your Nest Thermostat won’t stay charged, your battery is probably draining rather quickly. Confirm that it is actually drawing enough power from your HVAC system.

Leave your Nest Thermostat Battery to charge for a while, manually plugging it in via USB, so that it can cross the threshold that puts it in sleep mode.

If this doesn’t seem to work, you’ll likely have to contact an electrician, or consider replacing the battery, as Li-ion Batteries are rather finnicky. If the battery looks swollen, replace it immediately.

How to Replace the Nest Thermostat Battery

You can only replace the Nest Thermostat devices’ batteries and not for the Nest Thermostat E or Nest Learning Thermostat range.

When you see a low battery warning on your Nest device, it is time to replace your Nest Thermostat’s batteries; here is what you can do:

1. Pull your Nest Thermostat off of the display
2. Turn it around and take out the old AAA alkaline batteries from the back
3. Insert the new AAA alkaline batteries into the device’s battery slots
4. Securely place the device back on display

Conclusion:

Troubleshooting my Nest Thermostat Battery not charging didn’t take a whole lot of things.

It was about as easy as fixing the delayed Message on the Nest Thermostat.

Understanding the reason behind the low battery levels is important to ensure that your Nest Thermostat is working correctly.

With the Nest Thermostat E and nest learning Stat, tackling low battery problems may be a little more challenging.

It would be best if you verified whether the unit is wired correctly, receiving a constant power supply, or whether its battery life is running out.

For the Nest Thermostat, on the other hand, it is as easy as replacing the batteries to ensure that your unit is as good as new.

You May Also Enjoy Reading:

• Nest Thermostat No Power To R Wire: How To Troubleshoot
• Best Smart Vents For Nest Thermostat You Can Buy Today
• Does Nest Thermostat Work With HomeKit? How To Connect
• How To Reset Nest Thermostat Without PIN
• Nest Thermostat Blinking Lights: What Does Each Light Mean?

Frequently Asked Questions

How do I know if my nest battery is charging?

A red blinking light on top of your Nest device means that your Nest device is charging, although the battery level is low.

Can I manually charge my Nest Thermostat?

You can manually charge your Nest Thermostat E and Nest Learning Thermostat with a compatible USB Cable.

If your Nest Thermostat shows a low battery warning, you can replace the batteries.

How do I check my nest battery level?

To check the battery levels on your Nest Thermostat E and Nest Learning Thermostat:

1. Go to the Menu option and select Settings.
2. Scroll until you find the Battery option.
3. It should have a battery icon next to it which changes according to the battery level.

What does flashing green light means on Nest thermostat?

A flashing green light on your Nest Thermostat means that the device is updating its software.