The Watts 0590719 is a high-performance 1/8 inch NPT air vent designed for veteran contractors who require reliable air elimination in pressurized hydronic heating systems. Engineered as a direct replacement for the DUOVENT-1/8, this unit features a rugged brass body and cover capable of handling system pressures up to 150 PSI and temperatures reaching 240°F. Its unique dual-function design incorporates an automatic vent with a black cap for continuous degassing and a manual vent with a red cap for high-velocity air removal during initial system fill. The internal assembly utilizes a high-temperature resistant polyethylene float and a silicone rubber seal, ensuring a positive shut-off even in systems with high concentrations of glycol. This automatic dual air vent is also effective as an anti-vacuum device, permitting air entry during system drainage to prevent collapsing. For long-term field maintenance, the entire assembly can be easily disassembled for cleaning the valve seat and float chamber. Key Benefits Dual-Vent Functionality: Combines automatic air discharge with a manual override for rapid system purging and commissioning. Glycol System Compatibility: The silicone rubber seal and polyethylene float are specifically designed to resist degradation in glycol-rich environments. Debris Resistance: Designed so the float line remains consistently below the valve seal, preventing system impurities from fouling the seat. Field Serviceable: The brass cover provides access for inspection and cleaning, ensuring the automatic air vent maintains optimal flow rates over time. Anti-Vacuum Protection: Functions as a vacuum breaker to facilitate smooth system drainage without air-lock issues. Common Questions Can the Watts 0590719 be used in chilled water applications? Yes, the DuoVent is rated for both hot and cold water distribution systems, with an operating range from 33°F to 240°F. How does the manual vent feature assist during installation? The manual red cap allows for high-capacity air elimination, which significantly reduces the time required to "burp" a residential or commercial boiler loop during the initial fill. Is this vent suitable for steam systems? No, this brass air vent is specifically engineered for hydronic (water and glycol) systems. Using it in steam applications may result in component failure. Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
