Description
The Caleffi 519700A Differential Pressure By-pass Valve is a precision-engineered brass valve designed to protect hydronic heating and cooling systems by maintaining proportional pump head pressure as zone valves open and close. With 1-1/4" NPT inlet and outlet connections, this adjustable by-pass valve automatically diverts excess differential pressure to reduce water hammer noise, stabilize flow, and improve overall system efficiency in multi-zone boiler and HVAC applications.
Features & Benefits:
-
Model: Caleffi 519700A Differential Pressure By-pass Valve
-
Connection Size: 1-1/4" NPT inlet and outlet
-
Adjustable pressure range (approx. 2–10 psi) for precise control
-
Maximum working pressure: 150 psi
-
Operating temperature up to 230 °F
-
Flow capacity up to 45 GPM
-
Durable brass body with stainless steel and EPDM internal components
-
Reduces water hammer and maintains stable differential pressure in hydronic systems
-
Ideal for multi-zone boiler, radiant heat, and HVAC hydronic applications
