1. Introduction
This manual provides essential information for the proper installation, operation, and maintenance of the Lennox OEM Replacement Furnace Control Board, model 103085-02. This control board is designed to replace original equipment manufacturer (OEM) parts in compatible Lennox furnace systems. Please read this manual thoroughly before attempting any installation or service.
2. Safety Information
WARNING: Electrical Shock Hazard. Disconnect power before servicing.
- Installation and servicing of heating, ventilation, and air conditioning (HVAC) equipment can be hazardous due to electrical components and sharp edges. Only qualified service personnel should install, repair, or service HVAC equipment.
- Always disconnect the main electrical power to the furnace before installing or servicing the control board to prevent electrical shock.
- Ensure all wiring connections are secure and comply with local and national electrical codes.
- Wear appropriate personal protective equipment (PPE), such as safety glasses and gloves, during installation.
- Verify that the replacement board is compatible with your specific furnace model before installation.
3. Product Overview
The Lennox OEM Replacement Furnace Control Board 103085-02 is a critical component responsible for managing the operational sequences of your furnace. It controls various functions including ignition, fan operation, and safety limits, ensuring efficient and safe heating. This board is a direct replacement for the original part, designed to restore full functionality to your HVAC system.
Figure 1: Lennox OEM Replacement Furnace Control Board 103085-02. This image displays the circuit board with various electronic components, relays, and terminal blocks for wiring connections. Key features include multiple relays for controlling different furnace functions, a fuse for circuit protection, and clearly labeled terminal blocks for power, thermostat, and component connections.
4. Setup and Installation
Installation of this furnace control board should only be performed by a qualified HVAC technician. Incorrect installation can lead to property damage, serious injury, or death. The following steps are general guidelines; always refer to your specific furnace model's service manual for detailed instructions.
- Power Disconnection: Turn off all electrical power to the furnace at the main service panel. Verify power is off using a voltage meter.
- Access Control Board: Locate and open the furnace access panel to expose the existing control board.
- Document Wiring: Before disconnecting any wires, take clear photographs of all wiring connections to the existing board. Label each wire and its corresponding terminal for accurate re-connection.
- Disconnect Wires: Carefully disconnect all wires from the old control board.
- Remove Old Board: Unmount the old control board from its housing. Note its orientation.
- Install New Board: Mount the new Lennox 103085-02 control board in the same position as the old one.
- Reconnect Wiring: Using your photographs and labels, carefully reconnect all wires to their correct terminals on the new board. Ensure all connections are secure. Refer to Figure 1 for a visual reference of the board's layout.
- Replace Fuse: If applicable, ensure the correct fuse (e.g., 3 amp or 5 amp, as specified by your furnace manufacturer) is installed in the fuse holder on the new board.
- Secure Panels: Close and secure the furnace access panel.
- Restore Power: Restore electrical power to the furnace at the main service panel.
- Test Operation: Initiate a heating cycle to verify proper furnace operation. Observe for any error codes or unusual behavior.
5. Operating Principles
The control board itself does not have user-operable controls. Its function is to interpret signals from the thermostat and safety devices, then execute the necessary actions to operate the furnace. This includes:
- Ignition Sequence: Initiating the igniter and opening the gas valve when a call for heat is received.
- Flame Sensing: Monitoring the flame presence to ensure safe combustion.
- Blower Fan Control: Activating the indoor blower fan at appropriate times during heating and cooling cycles.
- Safety Limit Monitoring: Shutting down the furnace if safety limits (e.g., high temperature, pressure switch) are exceeded.
- Diagnostic Codes: Providing diagnostic fault codes via an LED indicator to assist in troubleshooting.
Normal operation of the furnace is controlled by your thermostat settings. Ensure your thermostat is set to the desired mode (Heat, Cool, Auto) and temperature.
6. Maintenance
The Lennox 103085-02 control board is designed for reliable, long-term operation and typically requires minimal direct maintenance. However, regular maintenance of the overall furnace system is crucial for the longevity of all components, including the control board.
- Annual Furnace Inspection: Have your furnace inspected annually by a qualified HVAC technician. They can check for proper operation, clean components, and identify potential issues before they lead to control board failure.
- Keep Area Clean: Ensure the area around the furnace is clean and free of dust and debris, which can accumulate on electronic components and affect performance.
- Inspect Wiring: During annual inspections, ensure all wiring connections to the control board are tight and free from corrosion or damage.
- Check Fuse: Periodically inspect the fuse on the control board for signs of damage or being blown. Always replace with a fuse of the correct amperage rating.
7. Troubleshooting
Many furnace control boards include an LED indicator that flashes diagnostic codes to help identify issues. Consult your furnace's specific service manual for a list of these codes and their meanings. Common symptoms that may indicate a control board issue include:
- Furnace not starting or failing to ignite.
- Blower fan running continuously or not turning on.
- Intermittent furnace operation.
- No power to the thermostat or other furnace components.
- Repeated blowing of the control board fuse.
If you experience any of these issues, it is recommended to contact a qualified HVAC technician for diagnosis and repair. Attempting complex repairs without proper training can be dangerous.
8. Specifications
| Brand | Lennox |
| Model Number | 103085-02 (OEM Replacement) |
| Item Model Number (Manufacturer) | CECOMINOD048127 |
| Item Weight | 10 ounces |
| Product Dimensions | 6 x 6 x 6 inches |
| Manufacturer | Lennox |
| Part Number | CECOMINOD048127 |
| ASIN | B00FQHQKLU |
9. Warranty Information
Specific warranty details for the Lennox OEM Replacement Furnace Control Board 103085-02 are typically provided by the seller or manufacturer at the time of purchase. Please retain your proof of purchase for any warranty claims. For detailed warranty terms and conditions, contact the authorized Lennox dealer or the point of purchase.
10. Customer Support
For technical assistance, installation questions, or troubleshooting beyond the scope of this manual, please contact a qualified HVAC professional or an authorized Lennox service provider. You may also refer to the official Lennox website for additional resources or to locate a service technician in your area.
