Lennox 99K63 Rollout Switch provided the manual override is

provided the manual override is properly engaged during installation

single-throw (SPST) switch is engineered to withstand the rigorous thermal cycling common in modern high-efficiency systems

High Pressure Resilience: Rated for a maximum liquid pressure of 150 psig to maintain system integrity under stress

000 BTU/hr max multiple load capacity

This Bakelite back adaptor is specifically designed for dual temperature vertical or horizontal instruments

Lennox 99K63 Rollout Switch provided the manual override isThe Lennox 99K63 Rollout Switch is a critical safety component designed for precise thermal monitoring in residential and commercial gas furnaces. Engineered as a manual reset rollout switch, this part is calibrated to actuate at 250 degrees F (+ 12F), immediately interrupting the burner circuit if it detects flame rollout or excessive heat concentrations outside the combustion chamber. This OEM Lennox replacement part, also identified by part number