7-62
P/N 13772-005
Section 7
Cirrus Design
Systems Description
SR22T
cycled to ensure supply temperature is maintained below duct
temperature limits.
Conditioned air can be directed to passengers and/or the windshield
diffuser by manipulating the cabin vent selector mounted on the RH
instrument panel. The conditioned air enters the cabin through
adjustable air vents located in each kick plate and through non-
adjustable, floor level vents located in the rear cabin trim side panels.
Conditioned air can also be distributed to the windshield diffuser in the
glareshield.
Cooling
Standard cabin cooling is provided by ram air admitted through the
NACA inlet on the RH cowl to the fresh air valve, mounted to the
forward side of the firewall. When the fresh air valve is open, the air
flows into the cabin mixing chamber. When the fresh air valve is
closed, the cooled air exits into the engine compartment and is
exhausted overboard with the engine cooling airflow.
For airplane with optionally equipped Air Conditioning System, R134A
refrigerant enters the engine mounted compressor as a vapor and is
pressurized until the heat-laden vapor reaches a point much hotter
than the outside air. The compressor then pumps the vapor to the
condenser where it cools, changes to a liquid, and passes to the
receiver-drier. The receiver-drier’s function is to filter, remove moisture,
and ensure a steady flow of liquid refrigerant into the evaporator
through the expansion valve - a temperature controlled metering valve
which regulates the flow of liquid refrigerant to the evaporator. Inside
the evaporator, the liquid refrigerant changes state to a gas and in
doing so, absorbs heat. The evaporator then absorbs the heat from the
air passing over the coils and the moisture from the air condenses and
is drained overboard through the belly of the airplane. From the
evaporator, the refrigerant vapor returns to the compressor where the
cycle is repeated. During normal air conditioning operation, ram air
from the fresh air intake flows into the evaporator assembly, is cooled
as it passes through the evaporator coils, and is then ducted forward to
the distribution manifold. During maximum air conditioning operation -
or recirculation mode - the fresh air valve closes and valves in the
evaporator assembly open allowing cabin air to be recirculated and
further cooled as the air passes through the evaporator coils and
ducted forward to the distribution manifold.
Original Issue
