Honeywell VR425AF1003-1000 gas valve DN25

Honeywell VR425AF1003-1000 Class A gas control blocks are used to control and regulate the supply of gaseous fuel in high-power gas burners, atmospheric gas boilers, melting furnaces, incinerators and other gas consuming devices.

The Resideo VR425AF 1003-1000 gas valves are available for systems with spark ignition of the burner (DBI) and for systems with a pilot burner (IP).

As standard, the combined gas valves of the Resideo VR425 AF 1003-1000 are equipped with two main valves V1 and V2:

1. The V1 safety valve always opens/closes quickly;

2. The second valve (V2) can be operated either quickly (with flow control) or slowly (with flow control and adjustable opening).

A pressure control valve is located between valves V1 and V2.

There are 4 flange connections on both sides of the main body for the installation of any of the following devices:

• Inlet pressure switches of the C60VR series

• C60VR series intermediate pressure switch

• Valve Inspection System (VPS) + pressure switch

These accessories can be installed in different places of the main gas valve body of the Honeywell VR425AF1003-1000.

Technical specifications

• Body material: Aluminum alloy, injection molding

• Strainer: fine mesh mesh (diameter 0.34 mm), AISI 303 steel, can be cleaned by unscrewing the inlet flange screws. Meets the requirements for mesh filters according to EN 161.

• Closing spring: AISI 302 steel

• Valve plunger: with Fe 360 coating

• Seals and gaskets: hydrocarbon-resistant types of butadiene-acrylonitrile (NBR) and viton rubber.

• Minimum adjustment capacity: 1 m3/h.

• Maximum operating pressure: 200 mbar

• Valve classification: Class A + A according to EN 126/EN 161

• Regulator classification: Class C according to EN 126/EN 88

• Supply voltage: mains 230 V~, 50/60 Hz

• Other voltages – on request.

• Ambient temperature: -15 … 60 °C

• The flange kit contains:

1 flange with sealing plug

1 O-ring and 4 screws

1 pressure measuring fitting installed

• Housing: IP 40

Design and principle of operation

The gas valves of the Resideo VR425AF1003-1000 are controlled by devices with two positions that open and close the valves. Each device includes a coil and a sleeve, where there is a plunger connected to a rubber valve and covered with an anti-friction material.

These valves act as a system where spring pressure keeps them in the open position. The main component is a pressure servo controller with a pressure relief valve built into the diaphragm of the regulator controlling the control valve.

The supply of power to both devices leads to the flow of gas through the diaphragm into the system and the regulator. This creates a “servo gas” that lifts the membrane. When the control valve is open, the pressure generated by the Honeywell VR425AF 1003-1000 gas solenoid valve is regulated by the diaphragm via feedback.

When the pressure of the diaphragm exceeds the set value, the control valve partially reduces the operating pressure, which allows it to close proportionally. This keeps the exhaust pressure at the same level, regardless of changes in the intake pressure. When disconnected, a small volume of working gas from the regulator is discharged into the main chamber.

If pressure regulation is necessary, an adjustment screw is used. In case no regulation is required, the full pressure of the “servogas” determines the position of the control valve based on the pressure.

Mounting position

The gas valve can be installed at an angle of plus or minus 90 degrees to the vertical. The distance between the gas valve and the wall/floor must be at least 30 cm.

Standards

With regard to electrical safety, Honeywell VR425AF 1003-1000 gas valves can be used in devices that comply with the European standards of the EN 60335 series, which establish requirements for

The VR425 AF 1003-1000 gas solenoid valves also meet all standards for electromagnetic compatibility for non-industrial and industrial installations.