User manual

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mode switch (2) is moved to MAN. The temperature selector rheos-
tat knob is now deactivated, and the MAN TEMP CONT Switch (5) is
armed. Holding this switch to the HEAT or centered position applies
electrical power directly to the selected side of the hot air bypass valve
motor, and the valve will open or close accordingly.
Two cabin blowers are located in recirculation fan boxes on the left
and right sides of the cabin forward the of the wing door. The blowers
are controlled by a three-position switch labeled CABIN FAN (6). The
switch positions are labeled HI, OFF and LO.
During unpressurized flight, a ram-air ventilation system is available
through a duct extending from the ECS heat exchanger ram-air inlet.
A valve in the distribution box is controlled by a two-postion CABIN
AIR lever labled PRESS and OUTSIDE. This lever must be in the PRESS
position for pressurized flight. During unpressurized flight, the lever is
moved to the OUTSIDE position to open the valve door in the distribu-
tion box and permit air from the ram-air inlet to enter the distribution
system.