Xylem 401488 Hoffman Specialty Model 79 Water Main Vent Valve 3/4" Male x 1/2" Female NPT

The Xylem 401488 Hoffman Specialty Model 79 is a heavy-duty water main vent valve designed for automatic air venting in hot water, cold water, and glycol hydronic heating systems. This brass-bodied vent valve features a built-in check valve and is engineered for commercial and industrial applications where reliable air elimination is critical to system performance.

Key Features:

• 3/4" NPT male inlet x 1/2" NPT female outlet straight shank connections
• 75 PSI maximum operating pressure with 200 PSI maximum hydrostatic pressure rating
• Maximum operating temperature of 250°F for high-temperature applications
• Brass body construction for durability and corrosion resistance
• Built-in check valve prevents backflow and system contamination
• Removable top for easy maintenance and servicing
• Tapped at top for 1/8" NPT safety drain connection for moisture discharge
• Compact dimensions: 6-5/8" height x 2-1/2" diameter
• Suitable for water or glycol systems with specific gravity greater than 0.7

The Hoffman Specialty Model 79 automatically vents air from hydronic systems during initial fill and normal operation, preventing air pockets that reduce system efficiency and cause noise. Ideal for use on water mains in boiler systems, hot water heating loops, chilled water systems, and process applications. Part of the trusted Hoffman Specialty line, a Xylem brand with over a century of expertise in steam and hydronic system components.