the housing must be pre-drilled according to the included technical instructions

It operates efficiently within an ambient temperature range of 32°F to 104°F

Constructed with corrosion-resistant materials for extended service life in harsh chemical environments

Always verify the voltage output of your furnace control board before installation

This specific Lennox limit switch is often identified as 56M1301

Fenwal 35-725903-997 Remote Sensor R-410A the housing must be pre-drilledThe Fenwal 35 725903 997 Remote Sensor is a critical diagnostic and flame monitoring component designed for integration with Fenwal series ignition controls, specifically the Mark 10DX 117 and 35 72 series boards. Engineered for high temperature ionization sensing, this probe monitors flame conductivity to ensure safe and reliable furnace operation. Contractors typically deploy this surface mount flame sensor in commercial and residential HVACR