Install your Nest thermostat

The Nest app’s step-by-step instructions make it easy to install and wire your thermostat, so use it as your main guide. Refer to this article if you need extra help.

1. It’s important to have the latest version of the app to complete the setup. Download it from the Apple App Store or Google Play. If you don’t have an account, the app asks you to create one.
2. Tap Settings on the app home screen.
3. Scroll down and select Add product to start the setup instructions.
4. To tell the app which thermostat you want to install, scan the QR code on the back of the display or choose “continue without scanning” and select your thermostat model.
5. The app shows you how to install your thermostat. It asks you some questions about your thermostat wires. Answer them as accurately as possible.
   Tip: You get a custom wiring diagram for your system after you install the thermostat base.

2. Switch off power to your system

(You may have already completed this step.)

It’s important to protect your thermostat and your system. Turn off the power to your system and thermostat before you expose any wiring.

Your heating, ventilation, and air conditioning (HVAC) system can have multiple breakers, so make sure to turn them all off before you move on. To check if the power to your system is off, change the temperature on your thermostat by at least 5 degrees.

• If it’s winter, turn up the temperature to turn on the heating.
• If it’s summer and you have system cooling, turn down the temperature to activate your central air conditioning.
• Wait at least 5 minutes to check if your system turns on (you need to wait because many systems have a built-in delay).

You can listen for your system to turn on or put your hand near a vent to feel if there’s warm or cool air coming through. Learn how to turn the power off to your system.

3. Remove your thermostat's cover and take a picture

(You may have already completed this step.)

Once you’re sure the power is off, remove your thermostat’s cover.

Some thermostat covers pop off, while others need to be unscrewed. If you haven’t already, take a picture of your current wiring.

4. Get a wiring diagram from the app

(You may have already completed
this step.)

To get a custom wiring diagram for installation, follow the Nest app’s thermostat installation instructions.

Important: This illustration is only an example. Each system’s wiring is different. You must get your own custom wiring diagram with our Compatibility Checker.

Incompatible wiring

High voltage wires

If your thermostat is labeled 120V or 240V or has thick wires with wire nuts, your system is high voltage and isn’t compatible with the Nest thermostat. Do not connect the Nest thermostat to high-voltage wires. Learn more about high voltage wires.

Stranded wires

Nest thermostats are not compatible with stranded wires. Do not connect the Nest Thermostat to stranded wires.

Jumper wires are short wires between 2 connectors. The Nest thermostat doesn’t need them.

Keep your current thermostat, the photo of your wiring, and any jumper wires your current thermostat uses in a safe place.

That way if you ever decide to move and you want to take your Nest thermostat with you, you have everything you need to reinstall your current thermostat.

If you find 2 sets of labels on each connector on your old thermostat’s backplate, refer to Thermostat wires with 2 labels.

Peel off the labels from the quick start card that came with your Nest thermostat and attach them to the matching wires on your thermostat. You can also use the white labels for additional wires if needed.

Troubleshooting wire labels

If you have labels like W, Y, or R, use the wiring diagram that you created earlier to choose which labels to attach to these wires.

If you have different wire labels not covered here, refer to What thermostat wire labels mean.

If you removed your old thermostat without labeling your wires first, check the picture you took in step 2. If you don’t have a picture, you can check your system to try to determine your wires, or contact a Nest Pro.

Important: Turn off the power to your system to avoid blowing a fuse in your equipment. If you blow a fuse, your Nest thermostat won’t turn on, or may display a power error after installation.

After you remove the base, wrap the wires around a pen or pencil to ensure they don’t fall back into the hole in the wall. Then, patch and paint over any holes in your wall. You can also use the included trim plate to help hide scratches or screw holes on your wall.

Use the bubble level to make sure the Nest thermostat is level.

If you use the optional trim plate, place it on the wall before you install the Nest base.

Tip: You can paint the Nest trim plate to match the color of your wall. If you’d like to paint your trim plate, make sure to paint it before it's installed. Make sure not to get any paint on your wiring, the Nest base, or your thermostat's display.

Pull the wires through the center of the base, then attach it to the wall with the screws.

Important: Use a screwdriver, not a power drill to drive in screws for the Nest base. Drills can easily over-tighten the screws and crack the base and damage its electronics.

Use the bubble level to make sure the Nest thermostat is level.

The Nest screws are self tapping, so there’s no need to drill into soft materials. If you need to drill into harder things like wood, use a 3/32 or 2.5mm drill bit.

Connect the wires to your Nest thermostat’s base by following the wiring diagram that you got from the Nest app.

Press down on the connector button and insert the wire as far as it can go in. Then release the button.

The connector button should stay down. This confirms that the wire is properly seated.

Terminals with wires should stay pressed down.

If the button doesn’t stay down, take the wire out, straighten it, and put it back in as far as it can go. You may need to strip the end of your wire to make sure enough copper is exposed.

Important:

• Do not put more than one wire in each connector on the Nest base.
• Do not connect any “spare” wires to your Nest thermostat that were not connected to your old thermostat. Only use the wires on your Nest wiring diagram.

After all the wires are securely connected, push them down toward the wall to make sure they’re flush with the base. If your wires stick out too far, they can keep your thermostat display from connecting properly.

If your wires stick out from the wall, press them down.

Before	After

Line up the pin connector on the back of the display and push it onto the base until it clicks into place.

Tip: If you don’t hear the display click, use your thumb to push the wires further into the wall. This makes sure that the wires won't stop the display from connecting to the base.

After you turn the power back on, your Nest thermostat should power on automatically. If it doesn’t turn on, you might notice a blinking red light to indicate that the battery is charging.

Wait for the battery to charge or refer to Troubleshoot when your thermostat won’t turn on.

After it’s done starting up, the Nest thermostat guides you through setup.

Tip: Let your thermostat know about your home, and your heating and cooling system so it can help keep you comfortable and save energy.

You can also connect your thermostat to Wi-Fi so you can control it with the Nest app, and download important thermostat software updates. Learn more on how to set up your Nest thermostat.