PSNO Valve Operation
A PSNO Valve is always installed downstream of the filter. During standard operation, filtration mode, the PSNO Valve is fully open and flow or pressure to the field is not restricted. The solenoid is not energized at this time (See Figure 1).
During the flushing mode, the solenoid is energized and the PSNO Valve partially closes in order to provide the desired pressure to the filter for proper flushing. This is referred to as the sustaining mode. During the sustaining mode, the valve maintains a “set” upstream pressure regardless of flow rate or pressure variations (See Figure 2).
At the end of the flush cycle, the solenoid is de-energized and the PSNO Valve will fully open again.
Figure 1: PSNO Valve Filtration Mode - valve is fully open and upstream pressure is 30 psi.
Figure 2: PSNO Valve Flushing Mode - valve partially closes and upstream pressure raises to 40 psi (or any other adjustab;e set point).
4" PSNO PVC Valve
