Nest Thermostat Not Holding Charge? (Instant Fix Guide)

If your Nest thermostat not holding charge and you have no idea why this is happening, then you’ve come to the right place.

In this guide, we will unwrap everything from simple to technical steps to help you fix your Nest thermostat charging problem on your own in a matter of minutes.

When the Nest thermostat is not holding a charge, you must power cycle the device, inspect the thermostat’s wiring, and verify that the HVAC system is working.

Let’s first learn about the possible causes of this issue!

Why Is My Nest Thermostat Not Holding a Charge?

If your Nest thermostat is not holding a charge, there is undoubtedly a problem with the power supply to your thermostat, which can happen due to different factors.

One primary factor is the charging cable itself, so if your USB or C-Wire is faulty, it won’t provide sufficient A/C voltage. 

• Sometimes, the issue is a software bug that prevents the Nest thermostat battery from properly charging.

So, it’s better not to rush to conclusions just yet and inspect all of the possible causes:

Here’s everything that may prevent the Nest thermostat from holding charge:

Now that you know the possible causes, let’s proceed with the troubleshooting steps!

How to Fix When the Nest Thermostat Not Holding Charge?

Tip: Follow the guide chronologically!

1. Reset the HVAC Circuit Breaker

The first thing you need to do is reset the circuit breaker that powers your thermostat, as this is the main power source of your device.

This will run a power circulation on the entire system, clear out the temporary issues, and provide a consistent power voltage to your thermostat.

Follow these steps to reset the circuit breaker:

1. Turn off your Nest thermostat via the power button.
2. Head over to the HVAC circuit breakers in your home.
3. Find the circuit breaker that powers the thermostat.
4. Flip over the breaker switch and wait for 5 minutes.
5. Meanwhile, disconnect and firmly reconnect each wire.
6. Then, flip the breaker back and turn on the thermostat.

Hopefully, your Nest thermostat device will now be able to charge correctly. If the issue persists, move on to the next troubleshooting step…

2. Re-attach the Display to the Base

Thermostats frequently experience charging problems due to a loose connection between the display screen and the wall base.

If the display screen isn’t correctly aligned with the mounting base, it won’t properly communicate and will not receive a sufficient power supply for charging.

Solution? 

• Simply detach and firmly reattach the thermostat display on the base!

Alternatively, follow the steps below to re-mount the thermostat correctly:

1. First, disconnect the Nest thermostat power supply.
2. Hold the display screen and remove it from the base.
3. Look for any stuck or clogged objects on the sides. 
4. Verify to remove any dirt accumulation or obstruction.
5. Hold and put the display screen back on the base.

As your thermostat device is turned on, a red light blinks, indicating that the Nest thermostat is charging.

If the charging issue continues and your thermostat no longer displays a red blinking light, try the other steps below…

Note: The thermostat may not immediately start to charge, so wait for at least 3 minutes!

3. Manually Charge Your Thermostat

So if your Nest thermostat has power, not holding charge, then you need to charge it manually by connecting it to the USB cable to fix this issue temporarily.

In case of a recent power outage or surges in your home, the voltage may still be insufficient, underpowering the Nest thermostat.

To manually charge your Nest thermostat, follow these steps:

1. First, remove the thermostat display from its mounting.
2. Connect the USB cable to the thermostat USB-C port.
3. Connect the other end of the cable to the charger adapter.
4. Leave the thermostat for 2 hours for a complete charge.

Once your thermostat charging is complete, put the display screen back onto the base, and then check if the charging problem is resolved.

In case the charge holding issue persists, then possibly the problem is with your HVAC wiring or your thermostat base wiring, so keep reading!

Note: This step only applies to Nest Learning and Nest E Thermostats!

4. Inspect the Thermostat Wiring

It’s crucial to ensure all your Nest thermostat wires are securely connected to the base.

If any wires are worn out/disconnected, they could prevent the device from getting a sufficient power supply to charge the built-in battery properly.

Here is how to check the Nest thermostat wiring:

1. Turn off the Nest thermostat and stop the power.
2. Dismount the thermostat display from the base.
3. Snap a picture of the wiring setup for a backup.
4. Carefully unscrew all the wires from the terminals.
5. Inspect the wires and ensure the ends are straight.
6. Then, locate the C-Wire in the thermostat base.
7. Make sure that the 10 mm of the wire is exposed.
8. Once you’re done, reconnect all the wires back.

Make sure to follow the names of the wires and connectors. Then, reinstall the thermostat display on its base.

When ready, turn on the Nest thermostat and flip on the circuit breaker.

Note: If possible, we recommend you perform the same inspection on your HVAC wiring!

5. Replace the Thermostat Batteries

If you have a 1st Gen Nest thermostat device, then replacing the batteries may come in handy because, over time, batteries lose their working capacity.

Hence, if you have a 2nd or 3rd Gen thermostat, you can’t replace the batteries because they have built-in (rechargeable) batteries. 

Follow these steps to replace the Nest thermostat batteries:

1. Disconnect the Nest thermostat power supply.
2. Hold and remove the display from the mount.
3. Remove the thermostat compartment cover.
4. Gently remove the already installed batteries.
5. Put two AAA batteries inside the thermostat.
6. Close the battery cover and put the display in.

That’s it! Now that your Nest thermostat has a fresh battery installed, the charging should work!

Note: It’s recommended to use only high-quality battery replacement!

6. Update the Nest Thermostat System

Another highly effective solution would be to check for any Nest thermostat updates and install them as soon as possible.

Many users share that outdated firmware sometimes causes system issues and brings up a “Low Battery” error, even when the thermostat’s power works correctly.

Hence, you must update your Nest thermostat, so follow these steps:

1. First, press to reveal the Quick View menu.
2. Then, rotate to locate the “SOFTWARE” tab.
3. Click to enter the tab and select “UPDATE.”
4. The device will say “downloading update.”
5. Remain patient until the thermostat updates.

This method requires a reliable internet connection to your thermostat, and it may take up to two minutes for an update to be found.

However, the download time depends solely on the internet connection speed, so you must remain patient until your Nest thermostat is updated completely!

Tip: Nest thermostats update automatically, but we recommend checking for missed updates!

7. Factory Reset the Nest Thermostat

One more effective method you must attempt at home is to perform a factory reset on your Nest thermostat.

Although the reset will clear out all settings and configurations, you will have the opportunity to set up everything from scratch, which will clear any setting misconfiguration.

How to Factory Reset the Nest Thermostat?

1. First, press to open the Quick View menu.
2. Go to the “Settings” menu on the thermostat.
3. Move the ring to “Reset” and push to select.
4. Move the ring to “All Settings” and select it.
5. You will be prompted to reset the thermostat.
6. Select “Yes” and “Reset” to start the process.

After that, simply set up your Nest thermostat to get control over your HVAC.

However, if your thermostat is still not charging or holding a charge, you may be dealing with a dead internal battery, which specialized technicians can replace.

Tip: Before you contact the technician, contact Nest Support with details of the problem!

Quick Recap:

Hence, when your Nest thermostat not holding charge, reset the circuit breaker to refresh the power or manually charge the device via a USB cable.

If the problem persists, inspect the HVAC and thermostat’s wiring, update the device’s system, or factory reset your unit.

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