The fuse usually opens due to flames "rolling out" of the combustion chamber

Optimized Thermal Management: Shaded pole design provides natural internal overload protection for continuous duty cycles

Durable diaphragm construction engineered to withstand high-cycle residential and commercial heating demands

Designed for contractors requiring reliable York furnace limit switch solutions

Precision Voltage: Optimized for an open circuit mV range of 20 to 28 mV to minimize voltage drop issues across the lead

Lennox 15M20 Pressure Switch Els PW 17895 The fuse usually opens dueThe Lennox 15M20 Pressure Switch is a critical safety component designed for precise draft proving in residential and commercial furnaces and rooftop units. This OEM Lennox 15M20 switch is a single pole, single throw (SPST) normally open configuration that closes when it detects a pressure fall of . 10"wc. Built with a 1 4" barb connection for easy hose attachment, this air proving switch ensures the combustion air inducer is pulling sufficient vacuum