User manual

Page 49
Aircraft Operation Manual
Piper Cheyenne I, IA, II, IIXL
For ight simulation use only
produce the selected temperature.
To achieve manual control, the mode switch (2) is moved to MAN. The tempera-
ture selector rheostat knob is now deactivated, and the MAN TEMP CONT Switch
(5) is armed. Holding this switch to the HEAT or centered position applies electri-
cal 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 ight, a ram-air ventilation system is available through a
duct extending from the ECS heat exchanger ram-air inlet. A valve in the dis-
tribution box is controlled by a two-postion CABIN AIR lever labled PRESS and
OUTSIDE. This lever must be in the PRESS position for pressurized ight. During
unpressurized ight, the lever is moved to the OUTSIDE position to open the val-
ve door in the distribution box and permit air from the ram-air inlet to enter the
distribution system.