Lennox 73W18 Limit Switch 328140-751 Loop-Powered Efficiency: Operates using the

Loop-Powered Efficiency: Operates using the power from the controller loop

you must use a Totally Enclosed (TEAO) motor to prevent moisture from damaging the internal windings

The included high-voltage ignition cable and 42-inch flame sensor wire address common system lockout issues caused by carbon fouling or insulation breakdown in older harnesses

backflow isn't just an inefficiency—it's a risk to the compressor

this OEM component delivers stable electronic feedback to the system controller

Lennox 73W18 Limit Switch 328140-751 Loop-Powered Efficiency: Operates using theThe Lennox 73W18 Limit Switch (Model 102857 05) is an essential OEM replacement part designed for high precision thermal protection in residential and commercial heating cycles. This auto limit control switch features a STILT design and is specifically calibrated to actuate at 150F (cut out) and automatically reset at 120F (cut in), maintaining a strict 30 degree differential to protect the heat exchanger from overheating conditions. Built with a