52W29 Furnace Flame Sensor Replacement - For Lennox Armstrong & Ducane Furnaces

52W29 Furnace Flame Sensor Replacement - For Lennox Armstrong & Ducane Furnaces52W29 Furnace Flame Sensor Key Features Monitors burner flame to ensure safe furnace operation. Direct replacement for the original manufacturer's part. Overall length: 5. 25 inches. Sensing rod length: 2. 75 inches. Constructed with a high temperature resistant metal rod and ceramic insulator. Replaces Cross Reference Part Numbers 52W29 52W2901 31L71 31L7101 LB 74940A 28PV41 903600 FLS52W29 Compatibility & Fitment Fits specific gas furnace models

52W29 Furnace Flame Sensor

Key Features

• Monitors burner flame to ensure safe furnace operation.
• Direct replacement for the original manufacturer's part.
• Overall length: 5.25 inches.
• Sensing rod length: 2.75 inches.
• Constructed with a high-temperature resistant metal rod and ceramic insulator.

Replaces / Cross-Reference Part Numbers

• 52W29
• 52W2901
• 31L71
• 31L7101
• LB-74940A
• 28PV41
• 903600
• FLS52W29

Compatibility & Fitment

• Fits specific gas furnace models from Lennox, Armstrong, and Ducane.
• Compatible with furnace series including G40, G41, G50, G51, G60, G61, and G71.

When to Replace

• Furnace ignites but shuts down after a few seconds.
• Furnace fails to heat consistently or at all.
• The sensor rod is visibly corroded, cracked, or has heavy carbon buildup that cannot be cleaned.

Installation Tips

• Disconnect all electrical power to the furnace before servicing.
• Handle the component by its metal bracket to avoid damaging the ceramic insulator.
• Ensure the sensor rod is properly positioned in the flame path for correct operation.
• Verify a secure wire connection before restoring power.