Lennox 32M86 Flame Sensor

The Lennox 32M86 Flame Sensor is a critical safety component designed for flame rectification in gas-fired heating systems. This OEM Lennox replacement part features a 3.01-inch single-prong electrode engineered to handle high-temperature environments without signal degradation. When the burner ignites, the 32M86 sensor sends a low DC microamp signal back to the integrated furnace control board. If the HVAC flame sensor fails to detect a consistent flame, the system will immediately initiate a safety shutdown of the gas valve to prevent the accumulation of unburned fuel. Professionals often identify a failing sensor when a Lennox furnace short cycles or hits a lockout code after ignition. This HVAC replacement probe is verified for compatibility with various Lennox, Armstrong, and Ducane units, replacing obsolete part number 32M8601. Its L-shape configuration ensures precise placement within the burner flame path for reliable safety circuit continuity.

• OEM Compatibility: Exact Lennox 32M86 dimensions ensure a direct fit for 3.01-inch single-prong requirements, eliminating the need for field modifications.
• Advanced Flame Detection: High-purity metal rod construction provides superior flame sensing accuracy for modern high-efficiency furnaces.
• System Reliability: Minimizes nuisance lockouts and short cycling issues caused by carbon buildup or cracked ceramic insulators on aged sensors.
• Safety Compliance: Restores the manufacturer-specified safety sequence to prevent gas leaks and ensure secure furnace operation.

• How do I check a Lennox 32M86 for failure? Use a multimeter set to DC microamps (µA) in series with the sensor wire; a healthy 32M86 usually reads between 2.0 and 5.0 µA depending on the control board.
• Can I clean this sensor instead of replacing it? While 220-grit sandpaper can remove temporary oxidation, microscopic cracks in the ceramic insulator or deep pitting on the rod require a full flame sensor replacement to maintain system integrity.
• Why does my furnace light and then shut off after 5 seconds? This is the classic symptom of a dirty flame sensor or a faulty 32M86; the board isn't receiving the rectification signal, triggering a safety cutout.

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.