Designed for zero differential pressure systems

suitable for most residential and light commercial pool heating loads

Precision Control: Restores factory-spec air-to-pressure response for accurate terminal unit water regulation

Common Questions How can I tell if my Parker 75520 coil has failed

Spence E-1 Valve Refrigerant Designed for zero differential pressureFor steam, air, and vapor systems, the Spence E 1 1" Main Valve serves as the reliable industry standard for rugged pilot operated pressure regulation. This 1 inch cast iron valve is designed for high performance service in HVACR and industrial steam plants, offering a normally closed, single seat configuration that ensures ANSI FCI 70 2 Class IV shutoff. The packless construction utilizes balanced metal diaphragms and a protected main spring to