Lennox 35K61 Limit Switch
The Lennox 35K61 Limit Switch is a critical high-temperature safety control designed for specific Lennox gas-fired furnaces and air handlers. This fixed temperature limit control features a 7-inch insertion length, making it compatible with deep heat exchanger configurations where accurate sensing of the primary heat zone is essential. With an auto-reset configuration, this switch is calibrated for an open temperature range of 195°F to 225°F, ensuring the system shuts down gas flow if the plenum temperature exceeds safe operating thresholds. For field technicians, the Lennox 35K61 serves as a direct OEM replacement (100101-13), maintaining the UL profile and safety sequence of the original equipment. It utilizes standard 1/4-inch spade terminals for quick integration into the existing 24V or 120V safety circuit. When diagnosing furnace limit switch tripping or blower motor cycling issues, verifying the 7-inch probe clearance is vital to prevent mechanical interference within the cabinet.
Key Benefits for HVAC Contractors- OEM Precision: Direct replacement for Lennox 100101-13, ensuring exact thermal response times and mounting alignment.
- Extended Probe Length: The 7-inch sensor insertion allows for accurate temperature monitoring in high-output heat exchangers.
- Automatic Reset: Eliminates nuisance lockouts by automatically closing the circuit once the plenum cools below the differential setpoint.
- Broad Compatibility: Engineered for use across various Lennox G-series and WhisperHeat furnaces.
- Durability: Built with high-grade ceramic and bimetal components to withstand constant thermal cycling without drift.
What causes a Lennox 35K61 to trip repeatedly?
Frequent tripping usually indicates restricted airflow, often caused by a restricted secondary heat exchanger, a dirty 16x25x1 filter, or an undersized return duct system. Verify the temperature rise across the heat exchanger against the data plate specifications.
Can I use a shorter probe if the 7-inch version is out of stock?
No. The Lennox 35K61 7-inch limit is specifically positioned to sense the hottest point in the airflow path. Using a shorter probe can lead to delayed response times and potential heat exchanger damage.
Is the 35K61 compatible with 80% and 90% AFUE furnaces?
Yes, this switch is utilized in both mid-efficiency and high-efficiency models, provided the 195-225 degree range and insertion depth match the original part number 100101-13.
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: $106.09
-65%$106.09
$37.13Lennox 35K61 Limit Switch
The Lennox 35K61 Limit Switch is a critical high-temperature safety control designed for specific Lennox gas-fired furnaces and air handlers. This fixed temperature limit control features a 7-inch insertion length, making it compatible with deep heat exchanger configurations where accurate sensing of the primary heat zone is essential. With an auto-reset configuration, this switch is calibrated for an open temperature range of 195°F to 225°F, ensuring the system shuts down gas flow if the plenum temperature exceeds safe operating thresholds. For field technicians, the Lennox 35K61 serves as a direct OEM replacement (100101-13), maintaining the UL profile and safety sequence of the original equipment. It utilizes standard 1/4-inch spade terminals for quick integration into the existing 24V or 120V safety circuit. When diagnosing furnace limit switch tripping or blower motor cycling issues, verifying the 7-inch probe clearance is vital to prevent mechanical interference within the cabinet.
Key Benefits for HVAC Contractors- OEM Precision: Direct replacement for Lennox 100101-13, ensuring exact thermal response times and mounting alignment.
- Extended Probe Length: The 7-inch sensor insertion allows for accurate temperature monitoring in high-output heat exchangers.
- Automatic Reset: Eliminates nuisance lockouts by automatically closing the circuit once the plenum cools below the differential setpoint.
- Broad Compatibility: Engineered for use across various Lennox G-series and WhisperHeat furnaces.
- Durability: Built with high-grade ceramic and bimetal components to withstand constant thermal cycling without drift.
What causes a Lennox 35K61 to trip repeatedly?
Frequent tripping usually indicates restricted airflow, often caused by a restricted secondary heat exchanger, a dirty 16x25x1 filter, or an undersized return duct system. Verify the temperature rise across the heat exchanger against the data plate specifications.
Can I use a shorter probe if the 7-inch version is out of stock?
No. The Lennox 35K61 7-inch limit is specifically positioned to sense the hottest point in the airflow path. Using a shorter probe can lead to delayed response times and potential heat exchanger damage.
Is the 35K61 compatible with 80% and 90% AFUE furnaces?
Yes, this switch is utilized in both mid-efficiency and high-efficiency models, provided the 195-225 degree range and insertion depth match the original part number 100101-13.
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 35K61 Limit Switch is a critical high-temperature safety control designed for specific Lennox gas-fired furnaces and air handlers. This fixed temperature limit control features a 7-inch insertion length, making it compatible with deep heat exchanger configurations where accurate sensing of the primary heat zone is essential. With an auto-reset configuration, this switch is calibrated for an open temperature range of 195°F to 225°F, ensuring the system shuts down gas flow if the plenum temperature exceeds safe operating thresholds. For field technicians, the Lennox 35K61 serves as a direct OEM replacement (100101-13), maintaining the UL profile and safety sequence of the original equipment. It utilizes standard 1/4-inch spade terminals for quick integration into the existing 24V or 120V safety circuit. When diagnosing furnace limit switch tripping or blower motor cycling issues, verifying the 7-inch probe clearance is vital to prevent mechanical interference within the cabinet.
Key Benefits for HVAC Contractors- OEM Precision: Direct replacement for Lennox 100101-13, ensuring exact thermal response times and mounting alignment.
- Extended Probe Length: The 7-inch sensor insertion allows for accurate temperature monitoring in high-output heat exchangers.
- Automatic Reset: Eliminates nuisance lockouts by automatically closing the circuit once the plenum cools below the differential setpoint.
- Broad Compatibility: Engineered for use across various Lennox G-series and WhisperHeat furnaces.
- Durability: Built with high-grade ceramic and bimetal components to withstand constant thermal cycling without drift.
What causes a Lennox 35K61 to trip repeatedly?
Frequent tripping usually indicates restricted airflow, often caused by a restricted secondary heat exchanger, a dirty 16x25x1 filter, or an undersized return duct system. Verify the temperature rise across the heat exchanger against the data plate specifications.
Can I use a shorter probe if the 7-inch version is out of stock?
No. The Lennox 35K61 7-inch limit is specifically positioned to sense the hottest point in the airflow path. Using a shorter probe can lead to delayed response times and potential heat exchanger damage.
Is the 35K61 compatible with 80% and 90% AFUE furnaces?
Yes, this switch is utilized in both mid-efficiency and high-efficiency models, provided the 195-225 degree range and insertion depth match the original part number 100101-13.
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.
