OEM Lennox Flame Sensor 102046-01 — 47W61

The genuine OEM Lennox 47W61 flame sensor (also numbered 102046-01) is the safety component that confirms a flame is present after the burners ignite. Using flame rectification, the 47W61 sends a small microamp signal to the control board to prove the burner is lit; if no flame is detected, the board safely shuts off the gas valve to prevent unburned gas from accumulating. This makes the flame sensor essential to both safe and reliable furnace operation.

Common failure symptoms: A dirty, corroded, or failing 47W61 typically causes the furnace to ignite and then shut down within a few seconds, short cycling on the burners, repeated ignition lockouts, or a no-heat condition even though the ignitor and gas valve are working. Oxidation buildup on the sensor rod is one of the most frequent causes of these faults.

Why OEM matters: The genuine Lennox 47W61 is manufactured to the precise rod length, mounting, and conductivity specifications your control board needs to read a stable flame signal. Aftermarket sensors can produce weak or erratic microamp readings that trigger nuisance lockouts. Installing the OEM flame sensor restores correct, safe flame detection and proper fit in your Lennox furnace.