Step by Step Wiring Guide for the Honeywell Home Pro Series User Manual
                     Step by Step Wiring Guide for the 
Honeywell Home Pro Series User 
Manual
Step-by-Step Wiring Guide for the Honeywell Home Pro Series Thermostat
Upgrading or replacing your thermostat with a Honeywell Home Pro Series Thermostat can enhance your 
home’s comfort, energy efficiency, and ease of control. However, proper installation is critical for the 
thermostat to function effectively. This step-by-step wiring guide will walk you through the process of 
wiring your Honeywell Pro Series Thermostat to ensure a successful installation.
Whether you’re replacing an old thermostat or installing a new one, following this guide will help you avoid 
mistakes and ensure everything is set up correctly. Honeywell Pro Series thermostat manual pdf
Before You Begin
Before starting the wiring process, make sure you have the following:
1. Honeywell Pro Series Thermostat (model depending on your setup)
2. Screwdrivers (Phillips and flathead)
3. Drill (if new holes are needed for mounting)
4. Level (to ensure the thermostat is installed straight)
5. Wire Strippers (to prepare wires if necessary)
6. Your System’s Wiring Information (e.g., how your existing thermostat is wired)
Safety First: Always ensure that the power to your HVAC system is turned off before starting the 
installation. You can do this by switching off the breaker controlling your heating and cooling system.
Step 1: Remove Your Old Thermostat
If you’re replacing an existing thermostat, you’ll need to start by removing it. Follow these steps:
1. Turn Off the Power: Ensure that both your HVAC system and your old thermostat are powered off.
2. Remove the Faceplate: Use a flathead screwdriver to gently pry off the old thermostat’s faceplate.
3. Inspect the Wires: Once the faceplate is off, you will see the wires connected to the back of the 
thermostat. Take note of where each wire is connected. You can use a phone to take a picture or label 
the wires with masking tape to keep track of which wire goes where.
Step 2: Understand Your HVAC System
The wiring process will vary depending on the type of HVAC system you have. Here are the most common 
setups:
 Conventional Heating and Cooling Systems (Heat Pump or Furnace + AC): These systems 
typically have five to six wires.
 Single-Stage Heating and Cooling Systems: These systems have a simpler setup with fewer 
wires.
 Two-Stage or Multi-Stage Systems: These systems require more complex wiring but can still be 
installed with the Honeywell Pro Series thermostat.
The key terminals you’ll encounter when wiring are:
 C (Common wire): This wire provides continuous power to the thermostat.
 R (Power wire): Supplies 24V power to the thermostat.
 Y (Cooling): Controls the cooling system.
 W (Heating): Controls the heating system.
 G (Fan): Controls the fan for your HVAC system.
 O/B (Heat Pump Reversal): Used for heat pump systems to reverse the flow of refrigerant.
If you're unsure about your system type, it’s always a good idea to consult with an HVAC professional.
Step 3: Prepare the Wires
Now that you understand your system and have removed the old thermostat, you can prepare the wires for 
installation:
1. Strip the Wires: If the wires are not already stripped, use a wire stripper to remove about 1/2 inch of 
insulation from the end of each wire. Be sure not to damage the wires underneath the insulation.
2. Check the Wire Condition: Ensure that the wires are in good condition. If they appear frayed or 
damaged, it’s important to replace them before proceeding.
Step 4: Mount the Honeywell Pro Series Thermostat
1. Attach the Mounting Plate: The Honeywell Pro Series Thermostat will come with a mounting plate 
that you’ll need to attach to the wall. Use a level to ensure that the plate is perfectly straight, then use 
a pencil to mark where the screws will go. Drill holes if necessary, then secure the mounting plate 
with screws.
2. Connect the Wires to the Thermostat Base: Next, connect the wires from your HVAC system to 
the corresponding terminals on the back of the Honeywell thermostat base. Here's a breakdown of 
the wire connections:
o R (Red): This wire is usually red and connects to the R terminal. It provides power to the 
thermostat.
o C (Blue or Black): The C terminal is for the common wire, which provides a return path for 
the 24V power.
o Y (Yellow): The Y terminal connects to the cooling system.
o W (White): The W terminal is for heating.
o G (Green): The G terminal connects to the fan control.
o O/B (Orange or White): If you have a heat pump system, connect the O/B wire to the O/B 
terminal.
Ensure that each wire is securely attached to its corresponding terminal by using the screw terminals or 
push-in connectors on the back of the thermostat base.
3. Check for a Secure Connection: Double-check the connections to make sure the wires are firmly in 
place. Loose wires can result in malfunctions or a thermostat failure.
Step 5: Attach the Thermostat to the Mounting Plate
Once the wiring is complete, align the thermostat unit with the mounting plate. Slide the thermostat into 
place until it clicks. Some models will have a simple "snap" feature, while others might require you to 
tighten screws to secure it.
Step 6: Power On the Thermostat
1. Turn On the Power: Go back to the circuit breaker and turn on the power to your HVAC system.
2. Activate the Thermostat: Your Honeywell Pro Series Thermostat should power up and display a 
welcome screen. If the screen doesn’t turn on, double-check the wiring connections and ensure the 
power is correctly restored.
Step 7: Test the System
Once your thermostat is powered on, test the system to ensure everything is working properly:
1. Set Temperature: Use the “Up” and “Down” arrows or touchpad to set the desired temperature.
2. Test Heating: Set the system to Heat mode and increase the temperature setting. The heating system 
should activate.
3. Test Cooling: Set the system to Cool mode and decrease the temperature setting. The cooling 
system should activate.
4. Test Fan: Set the thermostat to Fan On mode to verify that the fan runs independently of the heating 
and cooling system.
Step 8: Program Your Thermostat
Now that the wiring and basic functionality are confirmed, it's time to program your thermostat for 
automatic temperature adjustments:
1. Set the Date and Time: If prompted, set the current time and date.
2. Set Temperature Schedules: Use the “Schedule” button to set heating and cooling schedules. You 
can program up to four events: Wake, Leave, Return, and Sleep. This will ensure your HVAC system 
runs only when needed, saving energy.
Step 9: Final Check
1. Confirm All Settings: Review your thermostat settings to make sure they’re correct.
2. Secure the Thermostat Faceplate: If your thermostat has a removable faceplate, attach it once 
everything is configured.
3. Test All Features: Test all features once again to ensure that the system responds appropriately to 
mode changes, temperature adjustments, and fan settings.
Conclusion
Successfully wiring and installing the Honeywell Home Pro Series Thermostat can seem daunting at first, 
but following this step-by-step guide ensures a smooth process. Proper wiring is essential to the thermostat's 
operation, and by taking care during installation, you’ll have a reliable and efficient system that enhances 
your home’s comfort.
If you experience any issues with the wiring or setup, don’t hesitate to consult the user manual or contact 
Honeywell customer support. An incorrectly wired thermostat can cause operational issues, so always make 
sure the connections are correct before turning the power back on.
Once everything is in place, enjoy the comfort, convenience, and energy efficiency that your new Honeywell 
thermostat provides!