nest Learning Installation & Configuration Manual page 35

Humidifier Configurations
Stand Alone Humidifier, 1 Wire
•
This system has a humidifier that is separate from the HVAC system.
•
Install the hum wire directly into the * terminal.
•
Correctly ground the other wire from the Humidifier.
•
No relay is recommended.
Stand Alone Humidifier, 2 Wire
•
This system has a humidifier that is separate from the HVAC system.
•
Install the 2 hum wires directly into the relay.
•
Run the single wire from the relay to the * terminal.
•
Nest recommends the White Rogers 90-290Q or similar 24VAC HVAC relay.
34