Mixing Air Push-Pull Control - Cessna Grand Caravan 208B G1000 Manual

SECTION 7
AIRPLANE AND SYSTEMS DESCRIPTION

MIXING AIR PUSH-PULL CONTROL

A push-pull control, labeled MIXING AIR, GRD-PULL, FLT-PUSH, is
located on the cabin heat switch and control panel. With the push-pull
control in the GRD position (pulled out), warm compressor bleed valve
air is mixed with hot compressor outlet air in the mixer/muffler. This
mode is used during ground operation when warm compressor bleed
valve air is available (at power setting below 92% N
as additional bleed air heat to augment the hot compressor outlet bleed
air supply during periods of cold ambient temperature. With the push-
pull control in the FLT position (pushed in), cabin return air is mixed
with the hot compressor outlet air in the mixer/muffler. This recirculation
of cabin return air enables the heating system to maintain the desired
temperature for proper cabin heating. If desired, the FLT position of the
push-pull control can be used on the ground when ambient
temperatures are mild and maximum heating is not required. In this
mode, the excess warm compressor bleed valve air available at power
settings below 92% N
valve.
The mixing air push-pull control should always be in the
FLT position (pushed in) when the airplane is in flight.
Cabin return air must be allowed to flow through the
mixing valve and blend with hot compressor outlet air
during high engine power operation in order to maintain
proper temperature in the cabin heat distribution
system. If the FLT position is not used during flight, the
system may overheat and cause an automatic
shutdown.
U.S.
7-88
is exhausted overboard from the mixing air
g
CAUTION
CESSNA
MODEL 208B G1000
) and can be used
g
208BPHBUS-00