Lennox 78H74 Limit Switch 322838-753 Because the actuator can be

Because the actuator can be installed or replaced without draining the system or using tools

Can I program custom parameters on this board

those components must be salvaged from the existing assembly or sourced separately for a complete vent motor repair

but you should verify compatibility with specific corrosive chemicals before installation

Engineered for compatibility with "E" series main valves

Lennox 78H74 Limit Switch 322838-753 Because the actuator can beThe Lennox 78H74 is a critical OEM L185F limit switch designed for precision thermal protection in residential and commercial Lennox heating systems. As a primary safety control, this high limit switch monitors internal heat exchanger temperatures and is engineered to open the electrical circuit if the ambient temperature reaches the L185F set point. This rapid response prevents internal overheating and ensures the system operates within safe HVAC