VGD20.403U Siemens Gas Valve

Overview

The Siemens VGD20.403U is a modular, double-body gas valve designed for use in commercial and industrial burner systems. This normally closed, two-way valve integrates two safety shut-off valves into a single compact housing, significantly reducing the size and weight of the gas train. It is engineered to work in conjunction with Siemens SKP series electro-hydraulic actuators to provide safety shut-off, gas pressure regulation, or air-gas ratio control. Its robust aluminum construction and integrated stainless steel mesh filter ensure long-term reliability and protection of downstream components.

Features

• Double-body design combines two safety shut-off valves in series within a single unit
• Inlet valve features a flat disc for safety shut-off, while the outlet valve has a contoured disc for precise regulation
• Integrated 1-inch NPT vent connection located between the two valves
• Built-in 0.9 mm stainless steel mesh inlet filter protects valve seats and downstream components from contamination
• Dual stem guides ensure precise disc alignment and reliable, tight shut-off
• Compatible with AGF series threaded mounting flanges, allowing for easy removal and union-free installation
• Multiple 1/4-inch NPT pressure taps on the inlet, outlet, and between valves for easy monitoring

Specifications

• Model: VGD20.403U
• Connection Size: 1-1/2 inch NPT (requires two AGF flanges for installation)
• Vent Connection: 1 inch NPT
• Pressure Tap Size: 1/4 inch NPT
• Maximum Operating Pressure: 20 psi (1500 mbar)
• Close-off Pressure: 30 psi
• Operating Temperature: 14 F to 140 F (-10 C to 60 C)
• Body Material: Aluminum
• Approvals: UL listed, FM approved, CSA certified, and ISO 9001/14000 compliant

Applications

• Safety shut-off for gas-fired combustion plants and forced draft burners
• Gas pressure regulation and air-gas ratio control in industrial gas trains
• Use in power generation, chemical processing, and large-scale HVAC boiler systems
• Suitable for handling natural gas, propane, butane, and air
• Ideal for high-demand commercial and industrial environments requiring compact gas train configurations