Honeywell TH1110D2009 Manual PDF: A Comprehensive Guide
Welcome to your comprehensive guide to the Honeywell TH1110D2009 T1 Pro thermostat! This manual
provides detailed installation instructions and operational information.
Learn about wiring, setup options, troubleshooting, and maintenance.
Discover how to maximize your thermostat’s functionality with this comprehensive PDF.
This guide will help you understand every feature.
Overview of the Honeywell TH1110D2009 T1 Pro Thermostat
The Honeywell TH1110D2009 T1 Pro is a non-programmable thermostat designed for simplicity and ease
of use. It’s suitable for 24 VAC systems and supports single-stage heat and cool systems, including
both conventional and heat pump configurations. This thermostat offers manual changeover between
heating and cooling modes.
Its design prioritizes straightforward operation with soft-key controls and a clear, 2.37-square-inch
display. The T1 Pro utilizes the UWP mounting system for easy installation. It includes features
like adjustable temperature settings, fan operation controls, and installer setup options (ISU) for
customization.
The thermostat operates within a temperature range of 32 to 102 degrees Fahrenheit and maintains
accuracy with a +/- 1 degree Fahrenheit differential. Powered by two AA batteries, it ensures
reliable performance. The Honeywell T1 Pro provides a user-friendly interface for controlling your
home’s temperature.
Its non-programmable nature makes it ideal for users who prefer manual adjustments over preset
schedules. This thermostat is a practical choice for those seeking a simple, reliable, and effective
temperature control solution. The Honeywell T1 Pro combines functionality with ease of use.
Key Features and Specifications
The Honeywell TH1110D2009 T1 Pro thermostat boasts several key features that make it a reliable
and user-friendly choice for home temperature control. As a non-programmable thermostat, it offers
simple, manual operation, ideal for users who prefer direct control over their heating and cooling
systems. It supports both conventional (forced air and hydronic) and heat pump systems.
Key Specifications:
- Thermostat Type: Non-Programmable
- Voltage Rating: 20 to 30 Volt AC, 50/60 Hertz
- Switch Type: Relay
- Temperature Range: 32 to 102 degrees Fahrenheit
- Display Size: 2.37 square inches
- Dimensions: 4.062 x 4.062 x 1.156 inches
It features a manual changeover switch for easy transition between heating and cooling modes. The
thermostat includes a built-in compressor protection feature. The T1 Pro uses a thermistor sensing
element for accurate temperature readings and maintains a differential temperature of +/- 1 degree
Fahrenheit. The device is designed to operate within a humidity range of 5 to 90 percent.
Its white color and clean design allow it to blend seamlessly with any home decor. The T1 Pro also
features installer setup options. It is powered by standard AA batteries.
Installation Instructions: A Step-by-Step Guide
Installing the Honeywell TH1110D2009 T1 Pro thermostat is a straightforward process when
followed carefully. This step-by-step guide will walk you through the installation, ensuring a
secure and functional setup.
- Preparation: Turn off power to the heating and cooling system at the breaker or switch.
Remove the old thermostat from the wall. - Wiring: Identify and label the existing wires. Disconnect the wires from the old thermostat.
Do not disconnect any wires unless they are labeled. - Mounting: Use the UWP mounting system included with the T1 Pro. Secure the mounting plate
to the wall using the provided screws and anchors. An optional cover plate can be used to hide
any marks left by the previous thermostat. - Connecting Wires: Connect the labeled wires to the corresponding terminals on the T1 Pro’s
terminal block. Refer to the wiring diagrams in the manual for specific system configurations.
Ensure wires are securely attached to the terminals. - Final Steps: Attach the thermostat body to the mounted UWP plate. Insert the AA batteries
into the thermostat. Turn the power back on to the heating and cooling system.
Consult the Honeywell TH1110D2009 manual for detailed diagrams and troubleshooting tips.
Proper installation is crucial for optimal performance.
Wiring Conventional Systems: Forced Air and Hydronics
Wiring the Honeywell TH1110D2009 T1 Pro thermostat for conventional systems like forced air and
hydronics requires careful attention to terminal connections. Incorrect wiring can lead to
malfunctions or damage to your HVAC equipment. This guide provides essential instructions for
wiring these systems.
For forced air systems, identify the wires connected to your old thermostat. Common terminals
include R (power), W (heat), Y (cool), and G (fan). Connect these wires to the corresponding
terminals on the T1 Pro. If you have a separate transformer for heating and cooling, you might
need to use a jumper wire between the R and Rc terminals.
When wiring for hydronic systems, typically used for hot water or steam heat, you will likely
have fewer wires. Common terminals include R (power) and W (heat). Connect these wires to the
corresponding terminals on the T1 Pro. Ensure the thermostat is configured for hydronic systems in
the installer setup options (ISU). This setting adjusts the thermostat’s behavior to match the slower
response time of hydronic systems.
Always refer to the Honeywell TH1110D2009 manual for specific wiring diagrams and
troubleshooting tips. Confirm all connections are secure before restoring power to the system.
Wiring Heat Pump Systems
Wiring the Honeywell TH1110D2009 T1 Pro thermostat for heat pump systems requires careful
attention to terminal designations and system configurations. Unlike conventional systems, heat
pumps utilize a reversing valve to switch between heating and cooling modes, which affects the
wiring connections.
First, identify whether your heat pump system is a standard or a dual-fuel setup. Standard heat
pumps typically use terminals such as R (power), Y (compressor), O/B (reversing valve), and G
(fan). The O/B terminal determines whether the reversing valve is energized in heating (O) or
cooling (B) mode; consult your heat pump’s documentation to determine the correct setting.
Connect the corresponding wires from your old thermostat to the appropriate terminals on the T1 Pro.
If you have an auxiliary or emergency heat system, connect the wire to the AUX terminal. In the
installer setup options (ISU), configure the thermostat for heat pump operation and specify the
reversing valve setting (O or B).
Dual-fuel systems, which combine a heat pump with a fossil fuel furnace, require additional
consideration. The thermostat must be configured to manage the transition between the heat pump and
the furnace. Refer to the Honeywell TH1110D2009 manual for specific wiring diagrams and
configuration steps.
Understanding the Thermostat Controls
The Honeywell TH1110D2009 T1 Pro thermostat features a user-friendly interface designed for simple
and intuitive operation. Understanding the function of each control is essential for effectively
managing your home’s heating and cooling system.
The central element is the large, clear LCD display, which shows the current room temperature and the
setpoint temperature. The setpoint temperature is the desired temperature you want the thermostat to
maintain. To adjust the setpoint, use the up and down arrow buttons located on the right side of
the thermostat.
The mode button allows you to switch between different operating modes: Heat, Cool, and Off. 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.
The Off mode disables both heating and cooling.
The fan button controls the fan operation. You can set the fan to Auto or On. In Auto mode, the fan
runs only when the heating or cooling system is active. In On mode, the fan runs continuously,
providing constant air circulation.
The T1 Pro also includes soft-key controls, which are context-sensitive buttons that perform
different functions depending on the current screen. These buttons provide access to additional
settings and options, such as installer setup options (ISU) and filter change reminders.
Fan Operation Settings
The Honeywell TH1110D2009 T1 Pro thermostat offers straightforward fan control settings that allow
you to customize the airflow in your home. Understanding these settings is crucial for optimizing
comfort and energy efficiency.
The primary fan control is accessed via the “Fan” button on the thermostat’s interface. Pressing
this button toggles between two main fan operation modes: “Auto” and “On”.
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 only consumes power when it’s needed to distribute
heated or cooled air. When the thermostat calls for heat or cool, the fan will automatically turn
on to circulate the air throughout your home. Once the desired temperature is reached, both the
heating/cooling system and the fan will shut off.
In “On” mode, the fan runs continuously, regardless of whether the heating or cooling system is
active. This provides constant air circulation, which can help to even out temperature differences
between rooms and improve air quality by continuously filtering the air. However, it’s important to
note that running the fan continuously will consume more energy than using the “Auto” mode.
Choosing the appropriate fan setting depends on your individual needs and preferences. If energy
conservation is a priority, the “Auto” mode is the best choice. If you prioritize consistent
temperature and air circulation, the “On” mode may be more suitable.
Installer Setup Options (ISU)
The Honeywell TH1110D2009 T1 Pro thermostat includes Installer Setup Options (ISU) which allow
professionals or advanced users to customize the thermostat’s behavior to match specific system
configurations and user preferences. Accessing and adjusting these settings requires a basic
understanding of HVAC systems, so consulting the manual or a qualified technician is recommended.
ISU parameters are used to configure various aspects of the thermostat’s operation, such as the type
of heating and cooling system connected (e.g., conventional, heat pump), the number of heating and
cooling stages, temperature display format (Fahrenheit or Celsius), and temperature swing settings.
Properly configuring these settings ensures that the thermostat controls the HVAC system accurately
and efficiently.
For example, the ISU allows you to specify whether the thermostat is connected to a conventional
furnace or a heat pump. This is critical because heat pumps operate differently from conventional
systems, and the thermostat needs to be configured accordingly to control the reversing valve and
auxiliary heat correctly.
Temperature swing, also known as cycle rate or differential, determines how much the room
temperature is allowed to vary from the setpoint before the heating or cooling system is activated. A
smaller swing setting results in more frequent cycles and a more consistent temperature, while a larger
swing setting reduces the number of cycles and saves energy.
Before making any changes to the ISU settings, it’s crucial to consult the Honeywell TH1110D2009 T1 Pro
thermostat manual to understand the purpose of each parameter and the recommended settings for your
specific system. Incorrect settings can lead to inefficient operation, discomfort, or even damage to
your HVAC equipment.
Troubleshooting Common Issues
The Honeywell TH1110D2009 T1 Pro thermostat, while generally reliable, may occasionally encounter
issues. This section addresses some common problems and provides troubleshooting steps. Before
attempting any repairs, ensure power to the HVAC system is turned off at the breaker. Always consult
the manual for detailed instructions and safety precautions.
One frequent issue is a blank display. This could indicate dead batteries, so replace them with fresh AA
batteries. If the display remains blank, check the wiring connections to ensure they are secure and
correct. Another common problem is the thermostat not responding to temperature changes. Verify that
the thermostat is set to the correct mode (heat or cool) and that the setpoint temperature is
appropriately adjusted.
If the heating or cooling system runs constantly, even after reaching the setpoint, check the wiring for
shorts or loose connections. Also, ensure that the thermostat is not located in a drafty area or exposed
to direct sunlight, which can affect its temperature readings. If the system cycles on and off too
frequently, adjust the temperature swing setting in the Installer Setup Options (ISU).
For inaccurate temperature readings, verify that the thermostat is properly calibrated. Some models allow
for temperature calibration adjustments in the ISU. If the thermostat displays an error code, consult the
manual to identify the meaning of the code and the recommended action.
If you’ve exhausted these troubleshooting steps and the issue persists, it’s best to contact a qualified
HVAC technician for further assistance. Attempting complex repairs without proper knowledge can
potentially damage the thermostat or the HVAC system. Always prioritize safety and consult the manual
for guidance.
Maintenance and Battery Replacement
Proper maintenance ensures your Honeywell TH1110D2009 T1 Pro thermostat operates efficiently and
reliably. Regular cleaning prevents dust buildup that can affect temperature sensing. Gently wipe the
thermostat’s exterior with a soft, dry cloth. Avoid using liquids or abrasive cleaners, as they can
damage the unit.
Battery replacement is crucial for maintaining uninterrupted operation. The T1 Pro typically uses two AA
alkaline batteries. When the low battery indicator appears on the display, replace the batteries
immediately. Open the battery compartment, usually located on the front or side of the thermostat. Remove
the old batteries and insert new ones, ensuring correct polarity (+ and -).
It’s recommended to replace batteries annually, even if the low battery indicator hasn’t appeared. This
prevents potential battery leakage, which can damage the thermostat’s internal components. When replacing
batteries, use high-quality alkaline batteries for optimal performance and longevity.
Before replacing batteries, note any custom settings or configurations you’ve made in the Installer Setup
Options (ISU). While the thermostat usually retains these settings during battery replacement, it’s a
good practice to have a record in case they need to be re-entered.
Proper disposal of used batteries is essential for environmental responsibility. Check your local
regulations for battery recycling programs. By following these maintenance and battery replacement
guidelines, you can ensure your Honeywell T1 Pro thermostat continues to provide accurate temperature
control and reliable performance for years to come. Always refer to the manual.