Its self-acting design means it requires no external power supply

Helps maintain proper heat rejection and overall HVAC system efficiency

Integrated compressor short cycle protection extends compressor lifespan

and 220J models

Lennox 17U20 Pressure Switch 321894-709 Its self-acting design means itThe Lennox 17U20 Pressure Switch is a high precision sensing component engineered for critical monitoring in residential and commercial HVACR systems. This OEM Lennox 104371 10 replacement part is designed to actuate at 1. 00 inch W. C., providing essential safety interlocking for furnace draft inducer motors and air handling units. Built with a sensitive diaphragm and a robust SPST N. O. contact configuration, it ensures the electrical circuit closes