Honeywell TH3110D1008 Manual: A Comprehensive Guide
This guide provides detailed instructions for the Honeywell TH3110D1008 thermostat, covering installation, operation, troubleshooting, and accessing further resources.
It’s designed for both 1 Heat/1 Cool and 2 Heat/1 Cool systems, ensuring optimal temperature control and energy efficiency within your home environment.
Overview of the Honeywell TH3110D1008 Thermostat
The Honeywell TH3110D1008 is a non-programmable, digital thermostat designed for reliable and straightforward temperature management in residential settings. Part of the PRO 3000 Series, this thermostat offers simple controls for adjusting heating and cooling, making it ideal for users who prefer a manual approach to climate control.
It’s compatible with standard 24-volt heating and cooling systems, supporting both single-stage (1 Heat/1 Cool) and heat pump (2 Heat/1 Cool) configurations. The thermostat features a clear, easy-to-read display showing current temperature and setpoint. Users can easily switch between Heat, Cool, and Off modes, and adjust fan settings for either automatic operation or continuous airflow.
The TH3110D1008 prioritizes ease of use and dependable performance, offering a cost-effective solution for maintaining a comfortable indoor environment. It’s a direct replacement for many existing thermostats, simplifying the upgrade process.
Key Features and Specifications
The Honeywell TH3110D1008 boasts several key features, including a large, clear digital display for easy readability and simple push-button controls for intuitive operation. It supports both Fahrenheit and Celsius temperature scales, offering user preference flexibility. Compatibility extends to 24VAC systems, encompassing both conventional heating/cooling and heat pump setups (1H/1C or 2H/1C).
Specifications include: Voltage – 24VAC; Temperature Range – 50°F to 90°F (10°C to 32°C); Display Type – LCD; Power Source – 24VAC common wire (C wire) recommended, but can operate without it in some systems. The thermostat’s non-programmable design ensures consistent temperature settings without complex scheduling.
Its compact size and straightforward installation process make it a convenient upgrade for existing homes. The unit is designed for durability and reliable performance, providing years of consistent temperature control.
Package Contents and Initial Inspection
Upon opening the Honeywell TH3110D1008 package, carefully verify all components are present. You should find the thermostat unit itself, a mounting baseplate, mounting screws and anchors for wall attachment, and this user manual. Important: A wire label sheet is included to aid in accurate wiring during installation – do not discard this!
Inspect each item for any signs of damage incurred during shipping. Check the thermostat display for cracks or defects, and ensure the baseplate is free from bends or breaks. If any components appear damaged, do not proceed with installation. Contact Honeywell customer support immediately for assistance and potential replacement parts.
Before installation, familiarize yourself with the thermostat’s terminals and the included wiring diagram. Proper initial inspection ensures a smooth and successful setup process.

Safety Precautions and Warnings
Electrical Shock Hazard: Always disconnect power to your heating and cooling system at the breaker box before beginning any wiring or installation procedures. Failure to do so could result in serious injury or death. Caution: Equipment damage can occur if wiring is incorrect.
This device is intended for indoor use only. Do not expose the thermostat to direct sunlight, extreme temperatures, or moisture. Keep the unit away from flammable materials. Warning: Improper installation can void the warranty and potentially damage your HVAC system.
If you are uncomfortable with electrical wiring, consult a qualified HVAC technician for assistance. Ensure all wiring connections are secure and comply with local electrical codes. Always follow the provided wiring diagram carefully.

Installation Guide

Proper installation ensures optimal performance. This section details system compatibility checks, baseplate mounting, wiring connections, and initial power-up procedures for your thermostat.
Identifying System Compatibility (1 Heat/1 Cool, 2 Heat/1 Cool)
Before beginning installation, determine your heating and cooling system type. The Honeywell TH3110D1008 is compatible with both 1 Heat/1 Cool conventional systems and 2 Heat/1 Cool heat pump systems.
To identify your system, check your existing wiring and HVAC equipment. If you have a single heating source and a single cooling source, you likely have a 1 Heat/1 Cool system.
For heat pump systems, look for a reversing valve and two heating stages – auxiliary heat and the heat pump itself. Crucially, the model number on the thermostat itself (found by removing it from the wallplate) will indicate compatibility: TH3110D is for 1 Heat/1 Cool, while TH3210D is specifically for 2 Heat/1 Cool heat pump systems.
Incorrect wiring can damage your equipment, so accurate identification is paramount.
Mounting the Thermostat Baseplate
Begin by turning off power to your HVAC system at the breaker box. This is a crucial safety step before handling any wiring.
Remove your old thermostat, carefully noting the wire connections. Label each wire with the corresponding terminal designation for easy reference during installation.
Position the Honeywell TH3110D1008 baseplate on the wall, ensuring it’s level. Use the provided mounting screws to securely attach the baseplate to the wall. Utilize wall anchors if necessary, particularly if mounting to drywall.
Ensure the baseplate is firmly fixed and doesn’t wobble. A secure mounting is essential for proper thermostat operation and prevents potential wiring issues. Double-check the level before proceeding to the wiring stage.
Wiring Diagram and Terminal Connections
Refer to the wiring diagram included with your thermostat and carefully match the wires to the corresponding terminals on the baseplate. Common terminals include R (power), C (common), W (heat), Y (cool), and G (fan).
Securely insert each wire into the appropriate terminal, ensuring a firm connection. Loose connections can cause system malfunctions. Double-check all wiring against the diagram before proceeding.
For heat pump systems (TH3210D), additional wiring may be required for reversing valve control. Consult the diagram for specific heat pump configurations.
If you are unsure about any wiring connections, it is highly recommended to consult a qualified HVAC technician. Incorrect wiring can damage your system or create a safety hazard.
Powering On and Initial Setup
After securely connecting the wiring, restore power to your HVAC system at the breaker. The thermostat display should illuminate, indicating it’s receiving power. If the display remains blank, re-check the wiring connections and ensure the breaker is fully engaged.
The thermostat will guide you through an initial setup process. This typically involves selecting the system type (1 Heat/1 Cool or 2 Heat/1 Cool) and setting the date and time.
Follow the on-screen prompts to configure these settings accurately. Proper setup ensures the thermostat operates correctly and provides accurate temperature control. Verify the system type selection matches your HVAC configuration.
Once the initial setup is complete, the thermostat will display the current room temperature and allow you to begin setting your desired temperature preferences.

Operating Instructions

This section details how to effectively use your Honeywell TH3110D1008 thermostat, covering display navigation, temperature adjustments, mode selection, and fan control options.
Understanding the Display and Buttons
The Honeywell TH3110D1008 features a clear, easy-to-read digital display that shows the current room temperature and the set temperature; The display also indicates the current system mode – Heat, Cool, or Off – and fan setting (Auto or On).
The thermostat utilizes simple, intuitive buttons for operation. Typically, you’ll find “Temperature Up” and “Temperature Down” buttons to adjust the desired temperature. A “Mode” button allows you to cycle through the Heat, Cool, and Off settings. The “Fan” button controls the fan operation, switching between “Auto” (fan runs only during heating or cooling) and “On” (fan runs continuously).
Familiarizing yourself with these controls is key to comfortable and efficient climate control. The display will also show indicators for low batteries or system errors, prompting you to take appropriate action. Refer to the full manual for detailed explanations of all display icons and button functions.
Setting the Temperature
Adjusting the temperature on your Honeywell TH3110D1008 is straightforward. Use the “Temperature Up” and “Temperature Down” buttons on the thermostat faceplate to select your desired room temperature. Each press of the button typically adjusts the temperature by one degree Fahrenheit (or Celsius, depending on your setting).
The thermostat will display the set temperature, and the heating or cooling system will activate to reach and maintain that temperature. Note that there may be a slight delay before the system responds. The display clearly shows both the current room temperature and the temperature you’ve set.
For optimal comfort and energy savings, consider setting a temperature that balances your needs with energy efficiency. Avoid extreme temperature settings, and utilize the thermostat’s features to create a comfortable and cost-effective environment.
Switching Between Heat, Cool, and Off Modes
The Honeywell TH3110D1008 offers three primary operating modes: Heat, Cool, and Off. To cycle through these modes, use the “Mode” button located on the thermostat. Each press will advance the thermostat to the next available mode in the sequence – Heat, Cool, then Off, and back to Heat.
In Heat mode, the thermostat activates the heating system when the room temperature falls below the setpoint. In Cool mode, it activates the cooling system when the room temperature rises above the setpoint. Selecting “Off” disables both heating and cooling, allowing for manual control or ventilation.
The currently selected mode is clearly displayed on the thermostat’s screen. Ensure the correct mode is selected for your desired comfort level and seasonal needs, optimizing both comfort and energy consumption.
Fan Control Settings (Auto and On)
The Honeywell TH3110D1008 provides two fan control settings: Auto and On. These settings determine how the blower fan operates in conjunction with heating or cooling. The “Fan” button allows you to toggle between these modes.
In “Auto” mode, the fan operates only when the heating or cooling system is actively running. This is the most energy-efficient setting, as the fan isn’t continuously circulating air. Selecting “On” mode forces the fan to run continuously, regardless of whether heating or cooling is needed.
Continuous fan operation can improve air circulation and even out temperature distribution throughout your home. The selected fan setting is indicated on the thermostat display. Choose the setting that best suits your comfort preferences and indoor air quality needs.

Troubleshooting Common Issues
This section addresses frequent problems with the TH3110D1008, including power failures, inaccurate readings, and unresponsive systems, offering quick solutions for users.
Thermostat Not Powering On

If your Honeywell TH3110D1008 thermostat fails to power on, begin by verifying the system’s power supply at the circuit breaker or fuse box; ensure it hasn’t tripped or blown.
Next, carefully inspect the thermostat wiring, confirming all connections at the terminal block are secure and correctly matched to your system’s configuration. A loose wire can interrupt power.
If using batteries (some models require them as backup), replace them with fresh ones, even if the old ones appear to have some charge remaining. Low battery levels can prevent operation.
Double-check the C-wire connection, as a missing or improperly connected common wire is a common cause of power issues. If no C-wire exists, a C-wire adapter might be necessary.
Finally, if the problem persists, consult a qualified HVAC technician to diagnose potential issues with your heating or cooling system’s power supply or the thermostat itself.
Inaccurate Temperature Readings
If the Honeywell TH3110D1008 displays an incorrect temperature, first ensure the thermostat isn’t directly exposed to sunlight, drafts, or heat-generating appliances, as these can skew readings.
Verify the thermostat is level; an unlevel installation can affect accuracy. Use a small level to confirm proper positioning on the wall.
Check for obstructions near the thermostat that might block airflow and impact temperature sensing. Ensure vents aren’t blocked and furniture isn’t too close.
Consider calibration, though the TH3110D1008 doesn’t offer user calibration. If consistently off, professional HVAC service is recommended to assess sensor functionality.
Compare the thermostat’s reading with a reliable thermometer placed nearby. A significant discrepancy suggests a potential thermostat malfunction requiring professional attention.
System Not Responding to Thermostat Commands
If your heating or cooling system isn’t responding to commands from the Honeywell TH3110D1008, first check the circuit breaker for the HVAC system to ensure it hasn’t tripped.
Verify the thermostat is set to the correct mode (Heat, Cool, or Off) and that the set temperature is appropriately higher or lower than the current room temperature.
Inspect the wiring connections at the thermostat baseplate. Ensure all wires are securely connected to the correct terminals, referencing the wiring diagram.
Confirm the system’s power switch is turned on. Some systems have a separate power switch located near the furnace or air handler.
If issues persist, consult a qualified HVAC technician to diagnose potential problems with the system’s control board or other components.
Battery Replacement and Maintenance
The Honeywell TH3110D1008 thermostat requires battery replacement to maintain functionality during power outages or when the system’s power is interrupted. Use two AA alkaline batteries for optimal performance.
Low battery indicators will appear on the display when replacement is needed. Replace batteries promptly to avoid loss of settings or system control.
For routine maintenance, gently clean the thermostat’s display with a soft, dry cloth. Avoid using liquids or abrasive cleaners, as these can damage the surface.
Periodically inspect the wiring connections at the baseplate to ensure they remain secure. Loose connections can cause intermittent operation.
Avoid exposing the thermostat to extreme temperatures or humidity, which can affect its accuracy and lifespan.

Additional Resources
Access the complete PDF manual online for detailed safety guidelines, warranty specifics, and FCC compliance information regarding your Honeywell TH3110D1008 thermostat.
Downloading the Full PDF Manual
For a comprehensive understanding of your Honeywell TH3110D1008 thermostat, downloading the full PDF manual is highly recommended. This document contains detailed information beyond the scope of a quick start guide, including in-depth troubleshooting steps, advanced configuration options, and crucial safety precautions.
The PDF manual also includes valuable information regarding warranty details, FCC regulations, and potential hazards associated with improper installation or operation. You can readily access this resource online through the Honeywell Home website or various third-party document repositories. Searching for “Honeywell TH3110D1008 manual PDF” will yield several reliable download links.

Ensure the downloaded file is from a trusted source to avoid potential security risks. The complete manual provides a thorough reference for maximizing the performance and longevity of your thermostat, empowering you to resolve issues independently and maintain optimal comfort within your home.
Warranty Information and Contact Details
Honeywell provides a warranty for the TH3110D1008 thermostat, protecting against defects in materials and workmanship. Specific warranty terms, including duration and coverage, are detailed within the full PDF manual available for download. Carefully review these terms to understand your rights and responsibilities.
For warranty claims or technical support, contacting Honeywell directly is essential. Their customer service team can assist with troubleshooting, provide replacement parts if necessary, and guide you through the warranty process. You can find contact information – including phone numbers and email addresses – within the product manual and on the Honeywell Home website.
Retain your proof of purchase, as it’s typically required for warranty validation. Honeywell’s commitment to customer satisfaction ensures reliable support for your thermostat, maximizing its lifespan and performance.