1.16 HYDRAULIC SYSTEM Continued.
Placing the control switches in the positions corresponding to the above modes opens solenoid valves SV2
and SV4, and closes solenoid valve SV9 and valve PD1 by applying +24 Vdc to the coils. All remaining sole-
noids remain in their normal de-energized positions. The engine driven pump, through a combination of
gravity and suction, draws fluid from the hydraulic reservoir in the ECU and supplies pressure to the hy-
draulic control manifold. Fluid flows through the manifold and is then routed to the vent (NBC) fan, M3. The
fluid is returned to the manifold where it is divided by flow control FP3. Part of the fluid is supplied to the
recirculation fan, M2, and the balance is diverted around the motor in order to maintain proper speed con-
trol. The fluid flows through the compressor drive motor, M1A, and then through the condenser fan motor,
M1C. The total fluid flow is routed through solenoid valve SV7, then passes through the oil cooling heat
exchanger. The air flow action created by the condenser fan draws air over the heat exchanger, cooling the
hydraulic fluid. From there the fluid is routed to the reservoir mounted filter and returned to the reservoir.
Figure 1-13. Static Mode, Internal Power, Cool Mode,