This 3-inch L140-30F limit switch is a precise substitute for York, Luxaire, Coleman, and Evcon part number 025-29041-005. As a core furnace safety component, it opens the circuit at 140°F to shut down the heating system during overheating, then auto-closes at 110°F to restore normal operation once temperatures cool to a safe range. Engineered to match the original equipment's electrical ratings, 3-inch mounting dimensions, and temperature sensitivity, the switch fits designated York, Luxaire, Coleman, and Evcon furnace units perfectly. It integrates into the HVAC system without adapters, wiring modifications, or professional calibration. Equipped with a responsive bi-metal sensing mechanism, the switch triggers an immediate safety cutoff when internal furnace temperatures hit the 140°F threshold, preventing component burnout and fire hazards. The 30°F temperature differential ensures reliable auto-reset at 110°F for consistent heating performance. Constructed with premium temperature-resistant materials and a rugged housing, this limit switch withstands the harsh high-heat environment inside gas and electric furnaces. Its corrosion-resistant electrical contacts and sturdy frame handle frequent heating cycles, minimizing replacement frequency and maintenance costs. Designed for hassle-free drop-in installation, the switch requires no specialized HVAC skills to fit. Just disconnect the furnace power, label and remove the old switch's wires (take a photo for reference), secure the new S1-02529041005 in place, and reconnect the wires correctly—your furnace's safety function will be restored in minutes.