Lennox 20W36 Limit Switch
The Lennox 20W36 Limit Switch is a critical safety component designed for precise thermal regulation within Lennox residential furnace heating systems. Engineered as a 110-150F AUTO limit switch, this L150-40F thermal control monitors the heat exchanger temperature to prevent overheating conditions. When the high limit sensor detects temperatures exceeding the 150-degree threshold, it interrupts the burner circuit, resetting automatically once the ambient temperature drops by 40 degrees Fahrenheit. This 0.5-inch diameter flange-mount switch serves as a direct OEM replacement part for numerous Lennox G40, G41, and G51 series units. For HVAC contractors, the 20W36 provides a reliable solution for solving furnace limit switch tripping issues caused by restricted airflow or failing blowers. Proper installation ensures the furnace operates within designed thermal parameters, maintaining system integrity and long-term performance without the risk of heat exchanger damage.
Key Benefits for Contractors:
- Broad Compatibility: Fits a wide range of Lennox Elite and Merit series gas furnaces.
- Automatic Reset: Features a 40-degree differential for automatic thermal reset, reducing manual service calls.
- Precision Calibration: Factory-set at 150°F open and 110°F close tolerances for accurate cycling.
- Durable Construction: Built to withstand high-cycling environments in residential HVAC systems.
Common Installation Questions:
What causes a Lennox furnace to trip the high limit switch?
Most frequent causes include a dirty air filter, blocked return air ducts, or a malfunctioning blower motor causing low airflow across the heat exchanger.
How do I verify if the 20W36 limit switch is faulty?
Verify continuity across the terminals while the switch is cool; an open circuit during a cold state indicates a failed internal bimetal disc.
Is the 20W36 compatible with other brands?
This is an OEM Lennox part; while it may share specifications with other 150-degree switches, always verify the mounting flange and terminal orientation for specific furnace models.
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: $23.65
-65%$23.65
$8.28Lennox 20W36 Limit Switch
The Lennox 20W36 Limit Switch is a critical safety component designed for precise thermal regulation within Lennox residential furnace heating systems. Engineered as a 110-150F AUTO limit switch, this L150-40F thermal control monitors the heat exchanger temperature to prevent overheating conditions. When the high limit sensor detects temperatures exceeding the 150-degree threshold, it interrupts the burner circuit, resetting automatically once the ambient temperature drops by 40 degrees Fahrenheit. This 0.5-inch diameter flange-mount switch serves as a direct OEM replacement part for numerous Lennox G40, G41, and G51 series units. For HVAC contractors, the 20W36 provides a reliable solution for solving furnace limit switch tripping issues caused by restricted airflow or failing blowers. Proper installation ensures the furnace operates within designed thermal parameters, maintaining system integrity and long-term performance without the risk of heat exchanger damage.
Key Benefits for Contractors:
- Broad Compatibility: Fits a wide range of Lennox Elite and Merit series gas furnaces.
- Automatic Reset: Features a 40-degree differential for automatic thermal reset, reducing manual service calls.
- Precision Calibration: Factory-set at 150°F open and 110°F close tolerances for accurate cycling.
- Durable Construction: Built to withstand high-cycling environments in residential HVAC systems.
Common Installation Questions:
What causes a Lennox furnace to trip the high limit switch?
Most frequent causes include a dirty air filter, blocked return air ducts, or a malfunctioning blower motor causing low airflow across the heat exchanger.
How do I verify if the 20W36 limit switch is faulty?
Verify continuity across the terminals while the switch is cool; an open circuit during a cold state indicates a failed internal bimetal disc.
Is the 20W36 compatible with other brands?
This is an OEM Lennox part; while it may share specifications with other 150-degree switches, always verify the mounting flange and terminal orientation for specific furnace models.
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 20W36 Limit Switch is a critical safety component designed for precise thermal regulation within Lennox residential furnace heating systems. Engineered as a 110-150F AUTO limit switch, this L150-40F thermal control monitors the heat exchanger temperature to prevent overheating conditions. When the high limit sensor detects temperatures exceeding the 150-degree threshold, it interrupts the burner circuit, resetting automatically once the ambient temperature drops by 40 degrees Fahrenheit. This 0.5-inch diameter flange-mount switch serves as a direct OEM replacement part for numerous Lennox G40, G41, and G51 series units. For HVAC contractors, the 20W36 provides a reliable solution for solving furnace limit switch tripping issues caused by restricted airflow or failing blowers. Proper installation ensures the furnace operates within designed thermal parameters, maintaining system integrity and long-term performance without the risk of heat exchanger damage.
Key Benefits for Contractors:
- Broad Compatibility: Fits a wide range of Lennox Elite and Merit series gas furnaces.
- Automatic Reset: Features a 40-degree differential for automatic thermal reset, reducing manual service calls.
- Precision Calibration: Factory-set at 150°F open and 110°F close tolerances for accurate cycling.
- Durable Construction: Built to withstand high-cycling environments in residential HVAC systems.
Common Installation Questions:
What causes a Lennox furnace to trip the high limit switch?
Most frequent causes include a dirty air filter, blocked return air ducts, or a malfunctioning blower motor causing low airflow across the heat exchanger.
How do I verify if the 20W36 limit switch is faulty?
Verify continuity across the terminals while the switch is cool; an open circuit during a cold state indicates a failed internal bimetal disc.
Is the 20W36 compatible with other brands?
This is an OEM Lennox part; while it may share specifications with other 150-degree switches, always verify the mounting flange and terminal orientation for specific furnace models.
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.
