Lennox 52W29 Flame Sensor

The Lennox 52W29 Flame Sensor is a critical safety component designed for precise flame rectification in residential gas furnaces. As a high-performance OEM furnace flame sensor, it specifically monitors the burner's flame status, converting heat into a microamp signal that the integrated furnace control board processes during the ignition sequence. This Lennox furnace replacement part is the primary 52W29 flame sensor replacement for legacy models, including 31L7101, 31L71, and LB-74940A. Utilizing high-temperature ceramic insulation and a 4-7/8 inch straight sensing rod, this component ensures stable operation in harsh combustion environments. It is compatible with a wide range of Lennox series, such as G40, G43, G50, G51, and G60 units. When a furnace experiences short-cycling or fails to stay lit after the ignition strike, a fouled or oxidized Lennox 52W29 is often the root cause. This part features a 1/4 inch male spade terminal for secure electrical termination and rapid field installation.

• Direct OEM Compatibility: Engineered as the factory-spec 52W29 replacement for 31L7101, ensuring exact physical fit and electrical logic matching.
• High-Temperature Durability: Constructed with premium ceramic and metal alloys designed to withstand consistent exposure to burner flames without premature structural fatigue.
• Enhanced System Safety: Provides immediate gas valve shutdown if flame signal loss is detected, preventing hazardous unburned gas accumulation.
• Broad Application Range: Replaces multiple legacy part numbers including LB-74940A and 52W2901 across Lennox, Armstrong, and Ducane furnace lines.
• Optimized Signal Accuracy: Delivers a consistent and reliable microamp current to eliminate nuisance "no-flame" error codes.

• What are the symptoms of a failing Lennox 52W29 flame sensor? A common failure point is the furnace igniting for 2-5 seconds and then shutting down. This usually indicates the sensor is coated in carbon or silicate and cannot transmit a strong enough signal to the board.
• Can I clean the 52W29 sensor instead of replacing it? Light oxidation can sometimes be removed with a fine abrasive pad, but if the ceramic insulator is cracked or the metal rod is pitted, a full replacement is necessary to ensure reliable flame rectification.
• Does this part fit G40 and G60 series Lennox furnaces? Yes, the 52W29 is the standard service part for most G40, G43, G50, G51, and G60 series 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.