Honeywell Heat Pump Thermostat Wiring Diagram

Hello readers, welcome to our article on the Honeywell Heat Pump Thermostat Wiring Diagram. In this comprehensive guide, we will provide you with detailed information about the wiring diagram for Honeywell heat pump thermostats. Let’s dive in!

1. Understanding the Basics

Before we delve into the wiring diagram, let’s first understand the basics of a heat pump thermostat. A heat pump thermostat is a device used to control the temperature and operation of a heat pump system. It allows you to set the desired temperature and switch between heating and cooling modes.

Heat pump thermostats typically consist of several terminals and wires, each serving a specific purpose in the overall system. Understanding these terminals and wires is crucial for correctly wiring your Honeywell heat pump thermostat.

2. Terminal Designations

Each terminal on the Honeywell heat pump thermostat has a specific designation. These designations may vary depending on the model and manufacturer. However, the most common designations include:

Terminal Description
R Power Supply
C Common
Y Cooling
W Heating
G Fan
O/B Reversing Valve
Aux/E Auxiliary Heat/Emergency Heat
L System Monitor

Make sure to refer to the specific wiring diagram provided by Honeywell for your thermostat model to ensure accurate wiring.

3. Wiring the Heat Pump Thermostat

Now that we have a basic understanding of the terminal designations, let’s proceed to the wiring process. Here is a step-by-step guide on how to wire your Honeywell heat pump thermostat:

  1. Turn off the power to your HVAC system.
  2. Remove the cover of your old thermostat to expose the wiring.
  3. Take a picture or make a note of the existing wiring connections for future reference.
  4. Disconnect the wires from the old thermostat.
  5. Mount the new Honeywell heat pump thermostat on the wall, following the manufacturer’s instructions.
  6. Connect the wires to their corresponding terminals on the new thermostat, based on the wiring diagram.
  7. Securely fasten the wires and ensure they are properly insulated.
  8. Attach the thermostat cover.
  9. Turn on the power to your HVAC system.
  10. Configure the thermostat settings according to your preferences.

It is essential to double-check your connections and ensure they match the wiring diagram to avoid any potential issues or malfunctions.

4. Advantages of the Honeywell Heat Pump Thermostat

The Honeywell heat pump thermostat offers several advantages:

  • Precision Temperature Control: The thermostat allows precise temperature control, ensuring optimal comfort.
  • Energy Efficiency: Honeywell thermostats are designed to maximize energy efficiency, reducing energy consumption and utility bills.
  • Easy Installation: The wiring process is straightforward, making it easy for homeowners to install the thermostat themselves.
  • User-Friendly Interface: Honeywell thermostats feature user-friendly interfaces, making it simple to program and adjust settings.
  • Compatibility: The Honeywell heat pump thermostat is compatible with a wide range of heat pump systems, providing versatility for various HVAC setups.

5. Alternative Wiring Diagrams

In addition to the standard wiring diagram, Honeywell also provides alternative wiring diagrams for specific scenarios. These scenarios include:

  • Heat Pump with Auxiliary/Emergency Heat: This wiring diagram is suitable if your heat pump system has auxiliary or emergency heat.
  • Heat Pump with Dual Fuel: This wiring diagram is applicable if your heat pump system is combined with a fossil fuel furnace for dual fuel operation.
  • Heat Pump with Dehumidification: If your heat pump system includes a dehumidification feature, this alternative wiring diagram is for you.

Make sure to consult the appropriate alternative wiring diagram if your system falls into any of these categories.


In conclusion, understanding the Honeywell heat pump thermostat wiring diagram is crucial for proper installation and operation of your heat pump system. By following the correct wiring procedures and considering the alternative wiring diagrams, you can ensure optimal performance and comfort in your home. Enjoy the benefits of precise temperature control and energy efficiency with the Honeywell heat pump thermostat!


Q: Can I install the Honeywell heat pump thermostat myself?

A: Yes, the Honeywell heat pump thermostat is designed for easy installation, allowing homeowners to install it themselves. However, if you are not familiar with HVAC systems or electrical work, it is recommended to seek professional assistance.

Q: Are Honeywell thermostats compatible with all heat pump systems?

A: Honeywell thermostats are compatible with a wide range of heat pump systems. However, it is essential to check the compatibility of your specific thermostat model with your heat pump system before installation.

Q: Can I use alternative wiring diagrams for my Honeywell heat pump thermostat?

A: The alternative wiring diagrams provided by Honeywell are intended for specific scenarios. If your system falls into one of those scenarios, you can use the corresponding alternative wiring diagram. Otherwise, it is recommended to follow the standard wiring diagram.