1. Introduction
The Honeywell Home CT51N1008 Standard Heat/Cool Manual Thermostat provides a straightforward method for controlling your home's heating and cooling systems. This mercury-free thermostat is designed for ease of use, allowing precise temperature adjustments. It is compatible with central oil heating, electric furnaces, and central electric cooling options.
Figure 1: Front view of the Honeywell Home CT51N Thermostat, showing the temperature scale and control switches.
2. Key Features
- Mercury-free design.
- Precise temperature control for both heating and cooling systems.
- Standard heat/cool manual operation.
- Requires a 4-wire hookup.
- Compatible with central oil heating, electric furnaces, and central electric cooling.
- Designed for use in single transformer systems only.
- Works with heat pumps without auxiliary heat.
3. Setup and Installation
Important: Before beginning installation, ensure power to the heating and cooling system is turned off at the main fuse or circuit breaker panel to prevent electrical shock or equipment damage.
3.1 Mounting Location
Install the thermostat on an inside wall, approximately 5 feet (1.5 meters) above the floor. Avoid locations near windows, doors, or heat sources (lamps, sunlight, fireplaces, etc.) that could affect temperature readings.
3.2 Wiring Instructions
- Turn off power to the heating/cooling system.
- Remove the old thermostat cover and note the wire connections. Label each wire with the terminal designation (e.g., R, W, Y, G) before disconnecting.
- Mount the new thermostat base plate to the wall using the provided screws.
- Connect the wires to the corresponding terminals on the CT51N thermostat. This thermostat typically requires a 4-wire hookup. Refer to your system's specific wiring diagram if unsure.
- Ensure all connections are secure.
- Attach the thermostat cover to the base plate.
- Restore power to the heating/cooling system.
This thermostat is designed for single transformer systems only. Do not use with multi-transformer systems.
Figure 2: Dimensions of the Honeywell Home CT51N Thermostat, measuring approximately 2.88 inches wide, 1.38 inches deep, and 4.75 inches high.
4. Operating Instructions
The Honeywell Home CT51N thermostat features simple manual controls for temperature and fan operation.
4.1 System Switch (Heat/Off/Cool)
- Heat: Select this setting for heating operation. The system will turn on when the room temperature falls below your set temperature.
- Off: This setting turns off both heating and cooling systems.
- Cool: Select this setting for cooling operation. The system will turn on when the room temperature rises above your set temperature.
4.2 Fan Switch (Auto/On)
- Auto: In this setting, the fan runs only when the heating or cooling system is actively operating. This is the most common and energy-efficient setting.
- On: In this setting, the fan runs continuously, regardless of whether the heating or cooling system is actively operating. This can help with air circulation.
4.3 Temperature Setting
Adjust the temperature slider to your desired temperature. The thermostat will maintain the room temperature at this setting based on the selected system mode (Heat or Cool).
Figure 3: The Honeywell Home CT51N Thermostat seamlessly integrated into a contemporary room setting.
5. Maintenance
The Honeywell Home CT51N thermostat requires minimal maintenance.
- Cleaning: Periodically wipe the exterior of the thermostat with a soft, damp cloth to remove dust and dirt. Do not use abrasive cleaners or solvents.
- No Batteries: This thermostat does not require batteries for operation.
6. Troubleshooting
If you experience issues with your thermostat, refer to the following common troubleshooting steps:
| Problem | Possible Cause | Solution |
|---|---|---|
| System does not turn on (heating or cooling) | No power to the system; System switch in 'Off' position; Incorrect wiring | Check circuit breaker/fuse; Ensure system switch is set to 'Heat' or 'Cool'; Verify wiring connections are secure and correct. |
| Temperature reading seems inaccurate | Thermostat located near heat source or draft; Internal sensor obstruction | Relocate thermostat if possible; Ensure no objects are blocking airflow to the thermostat. |
| Fan does not run in 'On' mode | Fan motor issue; Wiring problem | Check fan wiring; Consult an HVAC professional if the fan motor is suspected. |
| System runs continuously or not at all | Faulty thermostat; Wiring issue | Verify wiring; If problem persists, the thermostat may need replacement. |
If these steps do not resolve the issue, contact a qualified HVAC technician for assistance.
7. Specifications
| Specification | Detail |
|---|---|
| Brand | Honeywell Home |
| Model Name | CT51N |
| Controller Type | Hand Control |
| Special Feature | Low Voltage |
| Color | White |
| Specific Uses For Product | Heat Pump |
| Temperature Control Type | Heating and Cooling |
| Connectivity Technology | N/A (Manual) |
| Included Components | Thermostat and instruction manual |
| Power Source | System Power (No Batteries Required) |
| Item Weight | 3.2 ounces |
| Product Dimensions | 2.88 x 1.38 x 4.75 inches |
| Material | Plastic |
| Display Type | Manual |
| Mounting Type | Wall Mount |
| UPC | 085267271196 |
| Item Model Number | CT51N1007 |
8. Warranty and Support
8.1 Warranty Information
This Honeywell Home CT51N thermostat comes with a 1-year limited warranty. Please retain your proof of purchase for warranty claims.
8.2 Customer Support
For technical assistance, troubleshooting beyond this manual, or warranty inquiries, please refer to the contact information provided with your product packaging or visit the official Honeywell Home support website.
