Lennox 78W99 Limit Switch 319847-401 this component is critical for

this component is critical for maintenance cycles involving the 15

High Flow Capacity: The 1/2" NPT threading ensures consistent gas flow for medium-to-high BTU appliances

Manual Reset Safety: High-limit lockout requires a technician's inspection before system restart

Mechanical imbalances in generic wheels often lead to premature bearing failure and excessive harmonic vibration

Lennox 78W99 Limit Switch 319847-401 this component is critical forThe Lennox 78W99 Limit Switch is a critical safety component engineered to regulate heat exchanger temperatures within Lennox G40, G41, G50, G51, and G61 gas furnaces. This L235 30F thermal limit control features a fixed temperature setting, designed to open the electrical circuit at 235F and automatically reset once temperatures drop by a 30F differential. Precision calibrated for high limit protection, this SPST (Single Pole Single Throw) switch