Xylem 401429 Model 74 Steam Unit Heater Air Vent 1/2" x 3/4" NPT

The Xylem 401429 is a Hoffman Specialty Model 74 steam unit heater air vent designed for efficient air removal in steam heating systems. This float-type thermostatic vent features a single non-adjustable port for reliable, maintenance-free operation in residential and commercial steam applications.

Key Features:

• Float-type thermostatic vent design for automatic air removal
• Single non-adjustable port configuration
• 1/2" NPT female x 3/4" NPT male straight shank connections
• Maximum operating pressure: 35 PSIG (2.4 bar)
• Temperature range: 140-240°F
• Steel body construction for durability
• Compact dimensions: 2-1/2" width x 5-3/8" height

Installation Requirements:

Install 6-10 inches (150-250mm) above the horizontal return line and at least 18 inches (450mm) above the boiler water line for optimal performance. The Model 74 is specifically engineered for steam unit heater applications where reliable air venting is critical to system efficiency.

Hoffman Specialty is a trusted Xylem brand offering comprehensive steam and hydronic system components for residential, commercial, and industrial applications.