1-The 3-inch, motor-operated valve provides a smooth cutoff of fuel to the single point panel during rapid off loading of fuel.
2-If the surge suppressor fail to operates the off load valve will prevent damage to system components from surges in the refuel manifold.
3- when placing master switch to drain position this will energized contacts of the off load valve relay.and fuel is pumped from the refueling and SPR manifolds into the No. 3 main fuel tank.