Nest Learning Thermostat Pro Installation & Configuration Guide Last updated: November 2017 Version: 1.
Table of Contents General Information 2 Nest Learning Thermostat Installation Features 2 HVAC System Compatibility 3 Technical Specifications 3 How to use Pro Setup 4 Installation Overview 5 Supported Wiring 7 Nest Thermostat Connectors 7 Wiring Diagrams: Conventional Heating/Cooling Systems 8 Wiring Diagrams: Heat Pump Systems 12 Wiring Diagrams: Multi-Speed Fans 17 Wiring Diagrams: Humidifiers and Dehumidifiers 18 Configuring Nest Thermostat with Pro Setup 19 How to use Pro S
General Information Nest Learning Thermostat Installation Features No jumper wires needed The Nest Thermostat does not use jumper wires, it will automatically jump terminals for you. Do not connect jumper wires to the Nest Thermostat. Before removing any wires from the old thermostat, including jumper wires, take a picture of the existing wiring configuration in case you or the homeowner need to reinstall it.
HVAC System Compatibility System 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) Y1 Y2 G O/B Rc Technical 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) Networking requirements: Connectors: ● ● ● ● ● ● ● ● ● ● ● W1 W2/AUX C ● ● Rh ● ● ● W
How to use Pro Setup When going through setup on the Nest Thermostat, the first question in the Equipment section asks if you’re a Homeowner or Pro. Selecting Pro will take you through Pro Setup, which has additional options to help professional installers setup more complex systems. In Pro Setup, you can configure advanced settings such as alternate and primary heating sources, lockout temperatures, fan activation and more.
Installation Overview 1. Confirm system compatibility Before opening the Nest Thermostat package, check all of the wires connected to the current thermostat against the list of available connectors on the Nest Thermostat box, or use the Compatibility Checker at http://nest.com/works to show you exactly where to connect each wire. 2.
. Walk through the Setup Interview with your customer Most of the Pro Setup questions are easy for a professional to answer, but your customer should answer some of the questions like prefered temperatures and Wi-Fi passwords. 8. Allow the Nest Thermostat to update If there’s a necessary software update, the Nest Thermostat will start downloading it as soon as it connects to the internet.
Supported Wiring Nest Thermostat Connectors Conventional connectors: Heat pump connectors: Y1 Stage 1 compressor relay Y1 Stage 1 compressor relay Y2 Stage 2 compressor relay, 2nd-speed fan relay Y2 Stage 2 compressor relay G Fan relay G Fan relay O/B Not used O/B Changeover valve relay Rc 24VAC power from cooling transformer* Rc Not used W1 Stage 1 heat relay W1 Stage 1 heat relay W2/AUX Stage 2 heat relay W2/AUX Auxiliary heat relay C Star 24VAC common wire * Rh Stage 3
Wiring Diagrams: Conventional Heating/Cooling Systems Conventional 1 Stage Heating Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ Conventional 2 Stage Heating Label: Func
Conventional 3 Stage Heating Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ Conventional 1 Stage Heating, 1 Stage Cooling Label: Function: Y1 Compressor Relay (Stage
Conventional 2 Stage Heating, 1 Stage Cooling Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ Conventional 2 Stage Heating, 2 Stage Cooling Label: Function: Y1 Compress
Conventional 3 Stage Heating, 2 Stage Cooling Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ Conventional 1 Stage Heating, 2 Stage Cooling Label: Function: Y1 Compr
Wiring Diagrams: Heat Pump Systems 1 Stage Heat Pump Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ 1 Stage Heat Pump with Aux Heat Label: Function: Y1 Compressor Re
1 Stage Heat Pump with Aux heat and Emergency Heat Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ 2 Stage Heat Pump Label: Function: Y1 Compressor Relay (Stage 1)
2 Stage Heat Pump with Aux Heat Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ Dual Fuel - 1 Stage Heat Pump, 1 Stage Heat Label: Function: Y1 Compressor Relay (
Dual Fuel - 2 Stage Heat Pump, 1 Stage Heat Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2) / A uxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ Dual Fuel - 1 Stage Heat Pump, 2 Stage Heat Label: Function: Y1 Compr
Dual Fuel - 2 Stage Heat pump, 2 Stage Heat Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2 ) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ 16
Wiring Diagrams: Multi-Speed Fans 2 Speed Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2 ) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, HUM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ 3 Speed Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor R
Wiring Diagrams: Humidifiers/Dehumidifiers Label: Function: Y1 Compressor Relay (Stage 1) Y2 Compressor Relay (Stage 2), 2nd-speed fan relay G Fan Relay* O/B Heat Pump Changeover Valve Rc 24VAC power from cooling transformer W1 Heat Relay (Stage 1) W2/AUX Heat Relay (Stage 2 ) / Auxiliary Heat Relay C 24VAC Common Wire † * Star: W3, E, H UM/DHUM, 3rd-speed fan relay Rh 24VAC power from heating transformer ‡ 18
Configuring Nest with Pro Setup How to use Pro Setup When you set up the Nest Thermostat for the first time, you'll be asked if you're a professional installer. If you answer "PRO," you'll receive Pro Setup options. Pro Setup can also be accessed at any time after the Nest Thermostat is installed through the SETTINGS menu. To enter Pro Setup on the Nest Thermostat after the initial setup go to SETTINGS > EQUIPMENT > CONTINUE > CONTINUE > PRO SETUP.
How to Configure Complex Systems Dual Fuel Systems If there’s an O/B wire and one or more W wires connected to the Nest thermostat (which indicates that the system uses a heat pump with an additional heating source), Pro Setup will first ask if the heating system is dual fuel or single fuel. For single fuel, any wires inserted into the W1, W2/AUX, or Star (if W3 is chosen) connectors will be treated as auxiliary heat that will be used simultaneously with the heat pump when needed.
Humidifier Pro Setup will show an Activate setting to specify whether heat needs to be activated for humidification to turn on. Bypass humidifiers should use the Hum. + heat option while steam, independent, or ondemand humidifiers should use the Hum. only option. Dehum with A/C Also known as AC integrated dehumidifiers, these systems require cooling to be activated to turn on dehumidification.
Forced Air HVAC Systems - Fan Activation Depending on your fuel source selection, you’ll need to determine when the fan activates for your customer’s heating system. Some systems will activate the fan automatically when the thermostat calls for heat. Some systems will rely on the thermostat to activate the fan. The default setting for fan control on the W1 wire is Don’t activate because most forced air gas heating systems will activate the fan automatically when the furnace (W1) is activated.
Troubleshooting Handling Unusual Thermostat Wiring When a B or X wire is a common wire Most thermostat manufacturers use C t o designate the connector for the common wire. However there are some Trane, American Standard, and York thermostats use B for the common wire. The NEMA standard designated the B wire as one of the change-over wires for some heat pump manufacturers. This is a simple issue to address: 1.
If the Nest thermostat isn't getting enough power from W or Y and there is no Common (“C”) wire While we find that in the vast majority of homes the Nest Thermostat can charge its built in battery by power sharing from the regular heating and cooling wires. But in some rare cases a common wire is needed to deliver consistent power to the Nest Thermostat while allowing normal operation of the heating and cooling system. If there is a common (C) wire installed the Nest Thermostat will not power share.
In a heat-only system, you need to bridge from common C to W. In a HVAC system with a Y wire, you must bridge from common C to Y. (Nest can only charge from W when Y is not connected.) Heat only systems Heating and cooling systems The heat call is detected by the controller board when the W wire is shorted to the R wire, which causes the 24V AC voltage to be detected.
Reference Materials “How To” Quick Reference Guide Action: Configuring Nest Thermostat for the installation location and HVAC system Steps: Just after installation, the Nest Thermostat will guide you through a set up interview, where you will configure it for the heating and cooling system it’s controlling and for the home or business where it’s installed. To help with HVAC configuration, the Nest Thermostat mechanically and electrically detects the wires inserted into its press connectors.
Switch between Heating, C ooling, and Range modes To switch to and from heating and cooling modes, follow these steps: Heat Pump: Setting compressor and auxiliary lockout temperatures Both auxiliary and compressor lockout temperatures can be changed in the Heat Pump section of the Equipment Settings menu. By default, the Nest Thermostat will lock out the auxiliary heater when the outdoor temperature is above 50°F but will not lockout the compressor at any temperature. 1. 2. 3. 4.
Setting fan speeds for systems with multi-speed fans Follow these steps: 1. 2. 3. 4. 5. Downloading the Nest App, creating an account and pairing the Nest Thermostat Press the ring to bring up the menu Select the Fan icon Choose System fan speed Select the fan speed you’d like to use when your system is heating or cooling your home. You can choose Low, Medium, High or Auto, depending on your system’s wiring.
Wiring error quick reference guide If the Nest Thermostat senses a problem with the wiring, you’ll receive an “E” error. These errors must be fixed before setup can continue. “N” errors are not as critical and setup will continue but certain features may not work. “W” errors indicate there is an issue with the Wi-Fi connection. “E” errors related to wires not being detected can be the result of a wire not being fully inserted into the connector or terminal.
E87 - Heat pump can have at most one auxiliary heat wire The Nest Thermostat was previously setup as a single fuel system with auxiliary heat, but it’s detecting W1 and * (W3) wires that aren’t supported in that configuration. E88 - Heat pump can have at most one auxiliary heat wire The Nest Thermostat was previously set up as a single fuel system with auxiliary heat, but it’s detecting AUX/W2 and * (W3) wires that aren’t supported in that configuration.
to equipment N72 - Power wire Rh detected. Not connected to equipment The Nest Thermostat isn’t electrically detecting the Rh wire, but one is connected to the Nest base. N73 - No power to W1 wire detected The Nest Thermostat isn’t electrically detecting the W1 wire, but one is connected to the Nest base. N74 - No power to Y1 wire detected The Nest Thermostat isn’t electrically detecting the Y1 wire, but one is connected to the Nest base.
Troubleshooting Quick Reference Guide Symptom: What’s going on: Nest doesn’t turn on after installation The internal battery is low and needs to charge. Red LED blinking on front Nest doesn’t turn on after installation If you leave it where it is, it will slowly charge and eventually turn on. This can take an hour or two. If you have a micro-USB cable and wall charger you can charge it more quickly over USB. The power was never turned back on.
Wi-Fi troubleshooting help can be found here: https://nest.com/support/article/Troubles hooting-Wi-Fi-and-connection-issues Forgot Lock Code Customer has forgotten the lock code to their Nest Thermostat The Nest Thermostat can be remotely unlocked by logging onto the Nest Account paired with their device from the Nest Web app or from the Nest Mobile app.
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.
Built-in Humidifier System, 2 Wire • • • • This system has a humidifier built into its HVAC system and 2 separate hum wires. 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. Built-in Humidifier System, 1 Wire • This system has a humidifier built into its HVAC system and only 1 hum wire. • Connect the hum wire from the built-in system directly to the * terminal.
Where to Find Additional Help • Help online: https://nest.
