01 Quick answers
Before you install: check your wires
This thermostat works with most 24V heating and cooling systems but not with line voltage (120V or 240V) systems like many electric baseboard heaters. Thick wires connected with wire nuts are a warning sign of a line voltage system.
- Turn off power to the HVAC system at the breaker.
- Remove the old thermostat faceplate and photograph the wiring and terminal letters.
- Run the compatibility checker in the Google Home app with those letters.
- If your system has no common (C or Rc) wire and the app says you need one, Google sells the Nest Power Connector, which installs at the furnace.
- Follow the app's wiring diagram, which is generated for the wires you entered.
If you see a wire labeled with a thick gauge or connected to 120V, stop and call an HVAC professional.
Resetting the thermostat
On the thermostat, open the settings menu and choose Reset. You can restart it, reset schedules, or do a full factory reset. A factory reset removes it from your Google account, so you'll need to set it up in the Google Home app again.
02 Finding the model number
The model is on the back of the thermostat and on the box. After setup, the Google Home app lists the device model and its wiring in the thermostat settings.
03 Specifications
| Voltage | Low voltage 24V systems |
| Connectivity | Wi-Fi, Google Home app |
| Power | AAA batteries plus system power, or Nest Power Connector |
| Display | Mirrored lens with touch sensor on the side |
Specifications can vary by region and production year. The rating label on the product is the final word.
04 What's in the Google Nest manual
The official owner's manual is organized into these main sections. Use them to find the right page once you open the PDF.
- 01What's in the box
- 02Compatibility check
- 03Removing the old thermostat
- 04Wiring
- 05Mounting
- 06Setup in the Google Home app
- 07Safety and regulatory
- 08Warranty
05 Owner questions
Does the Nest Thermostat work with a heat pump?
Yes, it supports many heat pump systems including those with an O/B reversing valve wire. Enter your wiring in the Google Home app to confirm your exact setup.
Why does my Nest Thermostat keep going offline?
Often it's low power. Without a common wire the thermostat relies on batteries and power stealing, which some systems don't support well. The Nest Power Connector usually fixes this.