Caleffi 501502A Air VentCaleffi 501502A is an extra hi capacity air vent with a 3 4" NPT connection, designed for NA548 & NA549 Series hydronic systems. This high capacity vent efficiently releases trapped air, helping prevent air locks and maintain steady system pressure and performance. Perfect for larger heating zones and high flow circuits, the Caleffi 501502A helps prevent air pockets that can reduce efficiency. Its rugged construction and compatibility with NA548 &

this small tube is a ready-to-use solution for routine valve care

The NC contact configuration and included auxiliary switch enable seamless integration with control systems

Built for durability and dependable performance

3-wire zone valve

Compliance & Size: UL approved

Nominal Size: 3/8 Inch

Cable: 3 ft 18 AWG plenum with 1/2 in conduit

2-position valve actuation with fast-opening solenoid operation

engineered to meet rigorous standards while offering straightforward installation

Universal ignition control for integrated HIS furnace control systems

Ideal for general service

Balanced rotation and quiet operation minimize noise during runtime