At the beginning of engine start, the fuel control supplies a pressure signal to the pressurizing and valve, causing the dump valve to close the manifold drain and open a passage for fuel flow to the engine. On engine shut down, fuel flow is cut off, pressure signal drops, and dump valve opens. The flow divider allows fuel to flow to the primary and secondary manifold, depending on fuel pressure.
A valve used in a turbine engine fuel system equipped with duplex nozzles. When the demand for fuel is low, it flows through the primary manifold. The pressurization valve opens at a high fuel flow to deliver fuel to the secondary manifold. At engine shutdown, the dump valve portion opens to drain fuel from the manifolds.