Lennox 20W37 Limit Switch
The Lennox 20W37 Limit Switch is a critical safety component designed for precise thermal regulation within residential gas furnaces and air handlers. Engineered as a 120-160F AUTO limit switch, this Lennox replacement part functions by monitoring the plenum temperature and breaking the electrical circuit if the discharge air exceeds the 160°F safety threshold. Once the unit cools to the 120°F reset point, the Lennox 20W37 automatically resets, allowing for continued operation. For technicians performing HVAC furnace repair, this switch is a direct OEM equivalent for multiple G24 and G26 series units, ensuring exact physical fitment and electrical calibration. Relying on high-grade bimetal sensing elements, this high limit safety switch prevents heat exchanger damage and ensures system longevity. Proper installation requires verifying the temperature range stamped on the bracket to maintain furnace high limit control standards and prevent nuisance tripping or hazardous overheating conditions.
- Automatic Reset Functionality: Transitions at 160°F and restores the circuit at 120°F without manual intervention.
- OEM Precision: Guaranteed compatibility with Lennox G24, G26, and early-model WhisperHeat systems.
- Safety Compliance: Prevents heat exchanger fatigue by maintaining strict discharge air temperature limits.
- Durable Construction: Built with robust ceramics and high-conductivity terminals to withstand high-duty cycles.
Common Technical Questions
What causes a Lennox 20W37 to trip frequently?
Nuisance tripping is often caused by restricted airflow, such as a clogged filter, undersized ductwork, or a failing blower motor, rather than a faulty 20W37 limit switch itself.
Is the 20W37 compatible with other furnace brands?
While primarily a Lennox OEM part, it can be used in other applications requiring a 120-160F auto-reset profile, provided the mounting footprint and terminal orientation match.
How do I test the Lennox 20W37 for continuity?
Using a multimeter set to ohms, check for a closed circuit (0 ohms) at room temperature. If the switch shows an open circuit (OL) when cold, the internal bimetal disc is likely defective.
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: $17.44
-65%$17.44
$6.10Lennox 20W37 Limit Switch
The Lennox 20W37 Limit Switch is a critical safety component designed for precise thermal regulation within residential gas furnaces and air handlers. Engineered as a 120-160F AUTO limit switch, this Lennox replacement part functions by monitoring the plenum temperature and breaking the electrical circuit if the discharge air exceeds the 160°F safety threshold. Once the unit cools to the 120°F reset point, the Lennox 20W37 automatically resets, allowing for continued operation. For technicians performing HVAC furnace repair, this switch is a direct OEM equivalent for multiple G24 and G26 series units, ensuring exact physical fitment and electrical calibration. Relying on high-grade bimetal sensing elements, this high limit safety switch prevents heat exchanger damage and ensures system longevity. Proper installation requires verifying the temperature range stamped on the bracket to maintain furnace high limit control standards and prevent nuisance tripping or hazardous overheating conditions.
- Automatic Reset Functionality: Transitions at 160°F and restores the circuit at 120°F without manual intervention.
- OEM Precision: Guaranteed compatibility with Lennox G24, G26, and early-model WhisperHeat systems.
- Safety Compliance: Prevents heat exchanger fatigue by maintaining strict discharge air temperature limits.
- Durable Construction: Built with robust ceramics and high-conductivity terminals to withstand high-duty cycles.
Common Technical Questions
What causes a Lennox 20W37 to trip frequently?
Nuisance tripping is often caused by restricted airflow, such as a clogged filter, undersized ductwork, or a failing blower motor, rather than a faulty 20W37 limit switch itself.
Is the 20W37 compatible with other furnace brands?
While primarily a Lennox OEM part, it can be used in other applications requiring a 120-160F auto-reset profile, provided the mounting footprint and terminal orientation match.
How do I test the Lennox 20W37 for continuity?
Using a multimeter set to ohms, check for a closed circuit (0 ohms) at room temperature. If the switch shows an open circuit (OL) when cold, the internal bimetal disc is likely defective.
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.
Product Information
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Description
The Lennox 20W37 Limit Switch is a critical safety component designed for precise thermal regulation within residential gas furnaces and air handlers. Engineered as a 120-160F AUTO limit switch, this Lennox replacement part functions by monitoring the plenum temperature and breaking the electrical circuit if the discharge air exceeds the 160°F safety threshold. Once the unit cools to the 120°F reset point, the Lennox 20W37 automatically resets, allowing for continued operation. For technicians performing HVAC furnace repair, this switch is a direct OEM equivalent for multiple G24 and G26 series units, ensuring exact physical fitment and electrical calibration. Relying on high-grade bimetal sensing elements, this high limit safety switch prevents heat exchanger damage and ensures system longevity. Proper installation requires verifying the temperature range stamped on the bracket to maintain furnace high limit control standards and prevent nuisance tripping or hazardous overheating conditions.
- Automatic Reset Functionality: Transitions at 160°F and restores the circuit at 120°F without manual intervention.
- OEM Precision: Guaranteed compatibility with Lennox G24, G26, and early-model WhisperHeat systems.
- Safety Compliance: Prevents heat exchanger fatigue by maintaining strict discharge air temperature limits.
- Durable Construction: Built with robust ceramics and high-conductivity terminals to withstand high-duty cycles.
Common Technical Questions
What causes a Lennox 20W37 to trip frequently?
Nuisance tripping is often caused by restricted airflow, such as a clogged filter, undersized ductwork, or a failing blower motor, rather than a faulty 20W37 limit switch itself.
Is the 20W37 compatible with other furnace brands?
While primarily a Lennox OEM part, it can be used in other applications requiring a 120-160F auto-reset profile, provided the mounting footprint and terminal orientation match.
How do I test the Lennox 20W37 for continuity?
Using a multimeter set to ohms, check for a closed circuit (0 ohms) at room temperature. If the switch shows an open circuit (OL) when cold, the internal bimetal disc is likely defective.
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.
