Lennox 36K29 Limit Switch
The Lennox 36K29 Limit Switch is a critical safety component designed for precise thermal monitoring in residential and light commercial gas furnaces. This furnace high limit switch features an auto-reset function, calibrated to trip when plenum temperatures reach the 210-240F range. When an overheat condition is detected, the switch opens the electrical circuit to the gas valve, immediately terminating the heating cycle to protect the heat exchanger from static pressure issues or airflow restrictions. Engineered for high-cycle reliability, the 36K29 is the direct OEM replacement for the Lennox 40154B020 and is often cross-referenced as part number 1N21L-2606. For technicians troubleshooting E250 error codes or furnace short cycling, this LPT switch provides a drop-in solution to restore system safety protocols. Its rugged construction ensures consistent temperature regulation in demanding industrial environments, maintaining the limit control standards required for Lennox heating equipment.
Key Benefits for Technicians- Direct OEM Compatibility: Verified as identical to 40154B020, ensuring zero-clearance issues during field installation.
- Automatic Reset Logic: Eliminates the need for manual intervention by resetting once the system cools to safe operating parameters.
- Precise Thermal Calibration: Factory-set for a 210-240 degree Fahrenheit window to prevent nuisance tripping while ensuring maximum safety.
- Universal Lennox Application: Fits a wide array of Lennox gas furnaces and heating units where high-limit protection is mandatory.
- Why is my furnace tripping the 36K29 switch? Frequent tripping is usually caused by restricted airflow. Check for a clogged air filter, closed supply registers, or a failing blower motor before replacing the switch.
- How do I verify if the 36K29 is faulty? Use a digital multimeter to check for continuity. Since this is a normally closed (NC) switch, it should show continuity at room temperature.
- Can I use a switch with a different temperature rating? No. Using a limit switch with an incorrect temperature range can lead to heat exchanger failure or fire hazards; always match the L240-30F specification.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Original: $139.51
-65%$139.51
$48.83Lennox 36K29 Limit Switch
The Lennox 36K29 Limit Switch is a critical safety component designed for precise thermal monitoring in residential and light commercial gas furnaces. This furnace high limit switch features an auto-reset function, calibrated to trip when plenum temperatures reach the 210-240F range. When an overheat condition is detected, the switch opens the electrical circuit to the gas valve, immediately terminating the heating cycle to protect the heat exchanger from static pressure issues or airflow restrictions. Engineered for high-cycle reliability, the 36K29 is the direct OEM replacement for the Lennox 40154B020 and is often cross-referenced as part number 1N21L-2606. For technicians troubleshooting E250 error codes or furnace short cycling, this LPT switch provides a drop-in solution to restore system safety protocols. Its rugged construction ensures consistent temperature regulation in demanding industrial environments, maintaining the limit control standards required for Lennox heating equipment.
Key Benefits for Technicians- Direct OEM Compatibility: Verified as identical to 40154B020, ensuring zero-clearance issues during field installation.
- Automatic Reset Logic: Eliminates the need for manual intervention by resetting once the system cools to safe operating parameters.
- Precise Thermal Calibration: Factory-set for a 210-240 degree Fahrenheit window to prevent nuisance tripping while ensuring maximum safety.
- Universal Lennox Application: Fits a wide array of Lennox gas furnaces and heating units where high-limit protection is mandatory.
- Why is my furnace tripping the 36K29 switch? Frequent tripping is usually caused by restricted airflow. Check for a clogged air filter, closed supply registers, or a failing blower motor before replacing the switch.
- How do I verify if the 36K29 is faulty? Use a digital multimeter to check for continuity. Since this is a normally closed (NC) switch, it should show continuity at room temperature.
- Can I use a switch with a different temperature rating? No. Using a limit switch with an incorrect temperature range can lead to heat exchanger failure or fire hazards; always match the L240-30F specification.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
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Description
The Lennox 36K29 Limit Switch is a critical safety component designed for precise thermal monitoring in residential and light commercial gas furnaces. This furnace high limit switch features an auto-reset function, calibrated to trip when plenum temperatures reach the 210-240F range. When an overheat condition is detected, the switch opens the electrical circuit to the gas valve, immediately terminating the heating cycle to protect the heat exchanger from static pressure issues or airflow restrictions. Engineered for high-cycle reliability, the 36K29 is the direct OEM replacement for the Lennox 40154B020 and is often cross-referenced as part number 1N21L-2606. For technicians troubleshooting E250 error codes or furnace short cycling, this LPT switch provides a drop-in solution to restore system safety protocols. Its rugged construction ensures consistent temperature regulation in demanding industrial environments, maintaining the limit control standards required for Lennox heating equipment.
Key Benefits for Technicians- Direct OEM Compatibility: Verified as identical to 40154B020, ensuring zero-clearance issues during field installation.
- Automatic Reset Logic: Eliminates the need for manual intervention by resetting once the system cools to safe operating parameters.
- Precise Thermal Calibration: Factory-set for a 210-240 degree Fahrenheit window to prevent nuisance tripping while ensuring maximum safety.
- Universal Lennox Application: Fits a wide array of Lennox gas furnaces and heating units where high-limit protection is mandatory.
- Why is my furnace tripping the 36K29 switch? Frequent tripping is usually caused by restricted airflow. Check for a clogged air filter, closed supply registers, or a failing blower motor before replacing the switch.
- How do I verify if the 36K29 is faulty? Use a digital multimeter to check for continuity. Since this is a normally closed (NC) switch, it should show continuity at room temperature.
- Can I use a switch with a different temperature rating? No. Using a limit switch with an incorrect temperature range can lead to heat exchanger failure or fire hazards; always match the L240-30F specification.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
