Lennox 73K20 Limit Switch
The Lennox 73K20 Limit Switch is a critical safety component designed for furnace high limit protection and temperature regulation in residential HVAC systems. As an OEM Lennox replacement part, this switch features a 3-inch insertion depth and operates on a 130-160F automatic reset logic. It is engineered to monitor heat exchanger temperatures, maintaining a normally closed circuit that opens upon reaching the 160°F high-limit threshold to prevent terminal overheating. The 73K20 limit control automatically re-engages once the plenum temperature drops to 130°F, ensuring continuous system operation without manual intervention. This HVAC limit switch is a direct substitute for various legacy Lennox furnace parts and is compatible with equipment from Allied, Armstrong, and Ducane. Professional installation is recommended to verify proper high limit switch settings and ensure the safety circuit integrates correctly with the existing ignition control board and gas valve assembly.
Key Benefits:- Precise Thermal Calibration: Factory-set 160°F open and 130°F close points provide accurate overheat protection for the heat exchanger.
- OEM Compatibility: Guaranteed fit for Lennox 73K20 and cross-referenced models, maintaining the original equipment’s safety certification.
- Automatic Reset Functionality: Eliminates the need for manual resets after nuisance trips, reducing emergency service calls for contractors.
- Durable Construction: Built with high-grade bimetal sensors and 3-inch probe lengths to withstand high-velocity airflow and repetitive thermal cycling.
- What causes a Lennox 73K20 to trip frequently? Frequent tripping often indicates restricted airflow caused by a dirty furnace filter, blocked ductwork, or a failing blower motor, rather than a defective switch.
- Can I use a 73K20 in place of a manual reset switch? No, this is an automatic limit switch. Replacing a manual safety with an automatic one can mask underlying combustion or venting issues, creating a safety hazard.
- Will this limit switch work with Ducane or Armstrong furnaces? Yes, the Lennox 73K20 is the designated replacement for several brands within the Lennox family, including Allied Air and Ducane.
130-160F AUTO Limit Switch
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: $27.28
-65%$27.28
$9.55Lennox 73K20 Limit Switch
The Lennox 73K20 Limit Switch is a critical safety component designed for furnace high limit protection and temperature regulation in residential HVAC systems. As an OEM Lennox replacement part, this switch features a 3-inch insertion depth and operates on a 130-160F automatic reset logic. It is engineered to monitor heat exchanger temperatures, maintaining a normally closed circuit that opens upon reaching the 160°F high-limit threshold to prevent terminal overheating. The 73K20 limit control automatically re-engages once the plenum temperature drops to 130°F, ensuring continuous system operation without manual intervention. This HVAC limit switch is a direct substitute for various legacy Lennox furnace parts and is compatible with equipment from Allied, Armstrong, and Ducane. Professional installation is recommended to verify proper high limit switch settings and ensure the safety circuit integrates correctly with the existing ignition control board and gas valve assembly.
Key Benefits:- Precise Thermal Calibration: Factory-set 160°F open and 130°F close points provide accurate overheat protection for the heat exchanger.
- OEM Compatibility: Guaranteed fit for Lennox 73K20 and cross-referenced models, maintaining the original equipment’s safety certification.
- Automatic Reset Functionality: Eliminates the need for manual resets after nuisance trips, reducing emergency service calls for contractors.
- Durable Construction: Built with high-grade bimetal sensors and 3-inch probe lengths to withstand high-velocity airflow and repetitive thermal cycling.
- What causes a Lennox 73K20 to trip frequently? Frequent tripping often indicates restricted airflow caused by a dirty furnace filter, blocked ductwork, or a failing blower motor, rather than a defective switch.
- Can I use a 73K20 in place of a manual reset switch? No, this is an automatic limit switch. Replacing a manual safety with an automatic one can mask underlying combustion or venting issues, creating a safety hazard.
- Will this limit switch work with Ducane or Armstrong furnaces? Yes, the Lennox 73K20 is the designated replacement for several brands within the Lennox family, including Allied Air and Ducane.
130-160F AUTO Limit Switch
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 73K20 Limit Switch is a critical safety component designed for furnace high limit protection and temperature regulation in residential HVAC systems. As an OEM Lennox replacement part, this switch features a 3-inch insertion depth and operates on a 130-160F automatic reset logic. It is engineered to monitor heat exchanger temperatures, maintaining a normally closed circuit that opens upon reaching the 160°F high-limit threshold to prevent terminal overheating. The 73K20 limit control automatically re-engages once the plenum temperature drops to 130°F, ensuring continuous system operation without manual intervention. This HVAC limit switch is a direct substitute for various legacy Lennox furnace parts and is compatible with equipment from Allied, Armstrong, and Ducane. Professional installation is recommended to verify proper high limit switch settings and ensure the safety circuit integrates correctly with the existing ignition control board and gas valve assembly.
Key Benefits:- Precise Thermal Calibration: Factory-set 160°F open and 130°F close points provide accurate overheat protection for the heat exchanger.
- OEM Compatibility: Guaranteed fit for Lennox 73K20 and cross-referenced models, maintaining the original equipment’s safety certification.
- Automatic Reset Functionality: Eliminates the need for manual resets after nuisance trips, reducing emergency service calls for contractors.
- Durable Construction: Built with high-grade bimetal sensors and 3-inch probe lengths to withstand high-velocity airflow and repetitive thermal cycling.
- What causes a Lennox 73K20 to trip frequently? Frequent tripping often indicates restricted airflow caused by a dirty furnace filter, blocked ductwork, or a failing blower motor, rather than a defective switch.
- Can I use a 73K20 in place of a manual reset switch? No, this is an automatic limit switch. Replacing a manual safety with an automatic one can mask underlying combustion or venting issues, creating a safety hazard.
- Will this limit switch work with Ducane or Armstrong furnaces? Yes, the Lennox 73K20 is the designated replacement for several brands within the Lennox family, including Allied Air and Ducane.
130-160F AUTO Limit Switch
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.
