These parts are functionally identical

Common Contractor Questions: Does this harness support both 24VAC and 12/24VDC systems

Manual Reset Mechanism: Ensures the system cannot automatically restart after a safety event

Is the 30/3 MFD rating compatible with 30/5 MFD systems

this is a universal-style HVAC pressure switch that can be used on any system requiring a 27 psi cut-out and 60 psi cut-in

Functional Devices PSH100A Power Supply Els PW 17895 These parts are functionally identicalThe Functional Devices PSH100A is a robust 100VA enclosed power supply engineered for demanding building automation and HVAC control applications. Designed to step down 120 VAC to 24 VAC, this Class 2 transformer provides consistent power for controllers, actuators, and sensors requiring precise voltage stability. Housed in a NEMA 1 rated metal enclosure, the PSH100A features a built in circuit breaker that eliminates the need for external fuse