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Nest Smart Thermostats are a great addition to your smart home and a good way to optimize your heating and cooling.
If your Nest Thermostat is connected to wiring, it will only use the battery during a power outage, so the battery can last up to one to two years. The battery can last up to 10 hours without a power source.
Knowing when and how to charge the Nest Thermostat battery is easy. There are also things you can do if you notice your Nest Thermostat battery is constantly draining.
How Long Does the Nest Thermostat Battery Last?
When it’s hooked up to a power supply, the battery inside your Nest Thermostat should last one to two years. In a power outage, the Nest Thermostat battery lasts up to ten hours.
The Nest Thermostat E and Nest Learning Thermostat both have a rechargeable battery, while the original Nest Thermostat runs on two AAA alkaline batteries.
If you have the original model, the amount of time your battery will last can vary significantly based on the quality of the batteries you use.
Only use high-quality batteries from a trusted brand to get the most power possible out of your thermostat.
How Do I Know If My Nest Thermostat Needs to be Charged?
Charging a Nest Thermostat, or any electronic device, when it doesn’t need to be can lower the average battery life. Before charging your rechargeable battery or replacing the AAA batteries, make sure your thermostat actually needs it.
If you have the original Nest Thermostat, you’ll receive a notification from the Google Home app and on your thermostat when the batteries start running low. You may also see a yellow symbol on your thermostat.
If you have a Nest Thermostat with a rechargeable battery, you can check the battery level on your thermostat:
- Open the Quick View menu.
- Select “Settings.”
- Tap “Technical Info.”
- Select “Power.”
- Find “Battery” and check the number listed.
If your battery level is 3.6V or lower, it needs to be charged until it reaches at least 3.8V.
If you don’t charge your Nest Thermostat, the screen will turn off and the system will disconnect from the Wi-Fi. It will still function until the battery is completely drained.
How to Charge the Nest Thermostat
If you have the original Nest Thermostat, you can charge it by changing the batteries. If you have any model of the Nest Learning Thermostat or the Nest Thermostat E, you’ll need to charge the rechargeable battery.
How to Charge a Rechargeable Nest Thermostat
To charge a Nest Thermostat with a rechargeable battery, you’ll need to remove it from the base. Then, you can follow these steps to start charging it:
- Look on the back of the Nest Thermostat and find the USB port.
- Depending on your model, plug either a micro-USB or mini-USB cable into the port and connect it to a power source.
Your Nest Thermostat should begin blinking a light on the front. Once you see this light, you can leave your thermostat to charge.
If your battery still has some charge left, it should take around a half hour to fully charge. If you’re charging it from a dead battery, it can take up to two hours.
You will know that your Nest Thermostat is fully charged when the blinking light at the top disappears.
How to Change Your Nest Thermostat Batteries
While most Nest Thermostats use a rechargeable battery, the original Nest Thermostat runs on three AAA alkaline batteries. When you’re ready, here’s how you can change your thermostat’s batteries:
- Remove the thermostat from the base.
- Remove the old batteries from the back.
- Replace the batteries with new ones.
- Replace the thermostat on the base. Make sure it clicks into place.
Troubleshooting a Nest Thermostat Battery
If you find that you’re charging your Nest Thermostat more often than you should, or if you’re constantly getting a message saying, “Your thermostat needs to shut down in order to recharge its battery,” there may be something wrong.
Why is My Nest Thermostat Battery Draining So Quickly?
Some reasons why your Nest Thermostat battery is draining more quickly than it should include:
- The Nest Thermostat battery is defective
- Electricity isn’t flowing to the Nest Thermostat
- A fuse has blown
If electricity isn’t flowing, try replacing your c-wire. If a fuse has blown in your circuit breaker, try flipping the switch.
A defective battery is a different situation. You can’t replace the rechargeable battery yourself, so you’ll need to contact Nest customer support for further assistance.
How Long Will a Nest Thermostat Last?
The average lifespan of a Nest Thermostat is approximately 10 years. To make your Nest Thermostat as long as possible:
- Always work within the operating temperatures
- Do routine maintenance when necessary
- Avoid placing your thermostat near magnetic fields