Here’s how to charge the Nest Thermostat and fix the low battery issue. Someone has installed hundreds of Nest Thermostats in his home over the years. He hasn’t encountered any problems with them. The Nest Thermostat’s battery can get low for a few reasons, which will require you to charge the device.

How to charge the nest thermostat?

When charging the Nest Thermostat there are a few things to consider because when the Nest Thermostat is not in use, it does not need to be charged. When functioning properly, your Nest Thermostat should automatically charge from the AC power provided by your HVAC system.

1. Make sure the power switch is on.

You have known a few people whose furnaces went out because they had accidentally turned the thermostat off while cleaning or remodeling. It is typically a light switch next to your HVAC system that controls its power. Make sure this switch is on.

The Nest will typically charge itself after connecting to power. The Nest may take several hours to recharge if it has been without power for a day or two. The Nest may take several hours to restore if it has been without power for a day or two. Additionally, you should check your circuit breaker to see if the electricity is on. Whenever you are unsure whether your HVAC system is powered on, remove the front cover and watch the LED circuit board lights. By holding down the “cover kill switch” with your free hand, you will be able to turn the furnace on. Give it a few hours to charge whenever the power has been off or the Nest has been sitting in a box for an extended period.

2. Remove Nest from the wall and let it charge.

It is easy to jumpstart your Nest Thermostat by taking it off the wall and charging it if it hasn’t been charging. The battery can be trusted, and once the battery is set you can use it to diagnose any issues you may have with Nest, HVAC, or wiring.

3. Use the same wire for all nest devices.

You can now test your HVAC System if you have tested the power at your HVAC system and have charged your thermostat manually by removing it from the wall and plugging it in. Try mounting the Nest Thermostat again on the wall-mounted plate and see how it works. It may be necessary to add an ordinary wire transformer if your Nest is reading low power or not charging. In the case of insufficient power from your HVAC system, a standard wire transformer is used to set your Nest Thermostat.

4. Replace Your Nest Thermostat Battery

If the problem is with the battery, we do not suggest you replace it until you have gone through Nest’s troubleshooting and confirmed that it is a problem. It is scarce to replace a Nest battery, but sometimes it happens. Our post about the Nest Thermostat Battery contains a comprehensive guide on replacing the Nest Thermostat Battery and troubleshooting.

If nest thermostat not charging

While we have shown you how to charge a Nest Thermostat, it is important to understand the reasons why it is not charging. There are a few common reasons why your Nest Thermostat won’t charge:

  1. The exhaust fan is not working; one of the most common problems is that your HVAC unit’s power is off. The switch on the machine or the circuit breaker may be tripped.
  2. Your HVAC Fuse Is Blown; inside your HVAC unit, there is a small 3AMP fuse; these can sometimes go bad. Replacements are available on Amazon.
  3. The Nest Thermostat does not receive enough power from your HVAC unit. If this is the case, there will need to be a standard wire or a standard wire transformer if this is the case.
  4. When air conditioning units fail, they automatically shut off the system, cutting the power to Nest Thermostats. As a result, your HVAC system needs to be troubleshot. Changing your furnace filter or cleaning your flame sensors are a few common problems quickly resolved. These furnace filters offer high levels of filtration for airborne particles, so I recommend them.
  5. The battery in your Nest thermostat is dead; this is extremely rare but does happen.

Nest thermostats are designed to charge their batteries using the wires of your heating and cooling system, so there’s no need to install any additional wiring. Battery drain, however, is a possibility if there are problems with the system. It will be necessary to pop off the display and use a micro-USB cable to connect to a power source. Please note that, if you own a Nest Learning Thermostat from the first generation, you must use a USB-A to miniature USB (Mini-B) cable. It could take up to two hours for a fully depleted battery to recharge. A wiring upgrade may be necessary if problems persist.

Read More: Boiler VS. Water Heater: All The Interesting Information You Need To Know

How long will the battery in the Nest thermostat last if there is no power?

A Nest thermostat’s battery typically lasts 2 to 3 hours without electricity. As a result, if your HVAC system is off and you don’t have a constant supply of electricity, your thermostat can still work for two to three hours.

How can I know if my Nest thermostat’s battery is running low?

If the battery in your Nest thermostat is low, you will get a low battery alarm on display. Additionally, repeated red flashes may be a sign of a low battery. If it’s not charging automatically, you may check your battery level to be sure and then set it using a USB connection.

How to fix nest thermostat battery problems?

A malfunctioning battery could occur over time. The Nest thermostat battery won’t charge, or the Nest thermostat won’t trust might be among the common issues you find online. Some forums can provide meaningful information, and some forums can be filled with fluff. Putting the battery back in can show you what is wrong. It can take one to two hours to connect the Nest device to the Micro USB port. Remove the Nest device from the wall and plug it in.

It is a temporary fix since charging the battery will ensure that the Nest thermostat works as generally as possible while investigating the issue. It is claimed that Nest batteries do not have low battery problems because they can maintain their charge via the Rc and Rh wiring in your HVAC system.


  • What is the charge status of my Nest?

When the thermostat is charging, a blinking light will appear on the front. You will notice that the color of the light will vary depending on how much battery power is left in the thermostat.

  • Does the Nest thermostat need to be charged?

You shouldn’t have to do anything to charge the Nest thermostat’s batteries since the wiring of your heating and cooling system will do the job.

  • Why does the Nest’s light blink green?

When the top of your Nest thermostat displays a blinking green light, the software is being updated, it’s starting up, or it’s restarting.