Nest Thermostat Installation

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Compatibility:

  ● Works with 95% of 24V systems: gas, electric, oil, forced air, heat pump & radiant

  ● Heating: 1, 2 and 3 stages (W1, W2, W3)

  ● Cooling: 1 and 2 stages (Y1, Y2)

  ● Power (C, Rh, Rc)

  ● Fan (including multi-speed) (G or G1,G2,G3)

  ● Humidifier or dehumidifier (HUM, DEHUM)

  ● Heat pump: with auxiliary/alternate and emergency heat (O/B, AUX, ALT, E)

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Networking requirements: 

 ● Wi-Fi is required for software updates and remote control with the Nest App 

 ● Wi-Fi 802.11 b/g/n, 2.4 GHz

 ● Secure: AES-128, SSL/TLS, WEP, WPA/WPA2

 

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Thermostat Connectors/Terminals:

 

"Conventional" connectors: 

Y1  - Stage 1 Compressor Relay

Y2 - Stage 2 Compressor Relay, 2nd Speed Fan Relay

G - Fan Relay

O/B - Not Used

Rc - 24v Power From Cooling System Transformer

W1 - Stage 1 Heat Relay

W2/Aux -2nd Stage Heat Relay

C - 24 Volt Common From Cooling System Transformer

Star "*" - Stage 3 heat (W3), humidification (HUM), or dehumidification (DEHUM), 3rd-speed fan relay

Rh - 24 Volt Power From Heating System Transformer

  

 

"Heat pump" connectors:

Y1 -  Stage 1 compressor relay

Y2 -   Stage 2 compressor relay

G - Fan relay

O/B - Changeover valve relay

Rc - Not used

W1 -  Stage 1 heat relay

W2/AUX -  Auxiliary heat relay

C - 24VAC common wire

Star "*" -  Emergency heat (E), humidification (HUM), or dehumidification (DEHUM)

Rh - 24VAC power from heating transformer*   

 

 

* No jumper wires required. You don’t need to hang on to any old jumper wires going from Rh (sometimes just called R) to Rc. Nest will automatically jump these two connectors.

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Wiring Diagrams: Conventional Heating/Cooling Systems