Valve Operation and Air Flow: Notes
WARNING: This page is about a different variant/trim than selected.
In the figure below, divided by the diaphragm, the part above X is charged with atmospheric air pressure, and the part below X is charged with tank pressure. Also, the part above Y is charged with tank pressure, and the part below Y is charged with canister pressure.
If the atmospheric air pressure port is A, tank pressure port is B, and canister pressure port is C, the air flows according to pressure difference from each port as shown in CONDITION OF PRESSURE REFERENCE .
CONDITION OF PRESSURE REFERENCE
| Condition of pressure | Flow |
|---|---|
| A < B (solenoid OFF) | B --> C |
| B < C (solenoid OFF) | C --> B |
| Solenoid ON | B <-- --> C |