The RAF 8R-31 is a Normally Closed (N.C) pressure sustaining valve.
The RAF 8R-31 is an electric On/Off valve, controlled by a 3-W plastic solenoid valve. When the solenoid is energized the valve opens and performs as a pressure sustaining valve, maintaining the set pressure constant regardless of flow-rate or pressure fluctuations.
The 3-W plastic pilot can be preset to a desirable minimum upstream pressure.
The 3-W plastic pilot and plastic solenoid together with Raphael's patented diaphragm enables smooth and precise control.