providing the exact air-to-gas ratio necessary for secondary heat exchanger longevity

For systems requiring advanced control

cross-brand compatibility is not recommended without verifying stem dimensions and bolt patterns

the 2528002S prevents heat loss through the vent and ensures that the burner flame remains stable and efficient

Resideo VCZAA1100 Valve Refrigerant providing the exact air-to-gas ratioThe Resideo VCZAA1100 Valve is a professional grade two way cartridge cage valve engineered for precise hydronic zone control in residential and light commercial HVAC systems. Featuring a 1 2" sweat connection and a 3. 5 Cv flow coefficient, this valve body is purpose built for high performance fluid handling. It safely manages hot or chilled water containing up to 60% glycol, making it a versatile choice for fan coil units, baseboard radiators, and