Set up Humidity Helper on your Nest Learning Thermostat (4th gen)

If you have a humidifier or dehumidifier system, you can use Smart Humidity and Cool to Dry to adjust the humidity level and set a Quiet Time schedule. You can customize your humidifiers and dehumidifiers simultaneously since Nest Learning Thermostat (4th gen) has terminals to support both.

For more information on using your air conditioner or heat pump to help reduce excessive humidity in your home, refer to Learn about Cool to Dry.

Humidification and Dehumidification

Note: This feature is only available if you have a humidifier or dehumidifier setup on your Nest Learning Thermostat 4th gen.

By default, your humidifier and dehumidifier are enabled. You can customize your humidification preferences through the Google Home app.

• With the Home app:
  1. Open the Home app .
  2. Tap Favorites or Devices .
  3. Tap your thermostat Settings Thermostat Humidity.
  4. Tap the Enable humidifier or Enable dehumidifier switch.
  5. Adjust your preferred humidity level.

Smart Humidity

The Smart Humidity feature uses outdoor weather to automatically adjust your humidifier setpoint, this helps to reduce condensation on windows or walls during cold weather.

• To turn on or turn off Smart Humidity:
  1. Open the Home app .
  2. Tap Favorites or Devices .
  3. Tap your thermostat Settings Temperature preferences Humidity Helper.
  4. Tap the Smart Humidity switch.

Note: By default, Smart Humidity is enabled. Smart Humidity doesn’t apply to Dehumidification.

Quiet Time

Humidifier and dehumidifier systems can be noisy. You can set a Quiet Time schedule during times when you don't want the system to interrupt your sleep.

Note: Quiet Time only affects humidification or dehumidification. It doesn't impact fans used during heating and cooling.

• With the Home app:
  1. Open the Home app .
  2. Tap Favorites or Devices .
  3. Tap your thermostat Settings Thermostat Humidity.
  4. Tap the Quiet Time switch.
  5. Adjust the times Quiet Time should turn on and off.
  6. Tap Save.

System configuration

Manage other settings for your humidifiers and dehumidifiers such as A/C or heat integration, relay orientation, and fan activation.

Heat integration

Humidifiers that are heat integrated can add moisture to the air while also warming it up.

1. Open the Home app .
2. Tap Favorites or Devices .
3. Tap your thermostat Settings Thermostat Humidity.
4. Tap System configuration.
5. In the A/C integration section, choose whether your system is Standalone or AC integrated.

Relay orientation when dehumidifier is active

Most dehumidifiers are active when relay is closed, but if you need to change this setting:

1. Open the Home app .
2. Tap Favorites or Devices .
3. Tap your thermostat Settings Thermostat Humidity.
4. Tap System configuration.
5. In the Relay orientation when dehumidifier active section, select whether your dehumidifier is active when the relay is Open or Closed.

Fan activation

Some humidifier or dehumidifier systems require a fan to push air in or out.

1. Open the Home app .
2. Tap Favorites or Devices .
3. Tap your thermostat Settings Thermostat Humidity.
4. Tap System configuration.
5. In the Fan activation section under Humidifier or Dehumidifier, choose to Activate or Don’t activate the fan when the system is on.