Cirrus SR22 Pilot Operating Handbook page 251

Cirrus Design Section 7
SR22 Airplane Description
the passenger air distribution system and allows maximum airflow to
the windshield diffuser. Rotating the knob full clockwise shuts off
airflow to the windshield diffuser and allows maximum airflow to the
passenger air distribution system. The control can be positioned to
allow any proportion of windshield and passenger air. Conditioned air
for the forward seats is routed to outlets under the instrument panel at
knee level. Conditioned air for the aft seats is routed to outlets beneath
the forward seats near the door posts and exits at floor level.
Cabin Heat Control
The amount of heated air allowed into the air mixing plenum is
controlled by rotating the Cabin Heat Control. The control is
mechanically linked to a door in a heater box between the heater muff
and the mixing plenum. Rotating the control full counterclockwise
(HEAT OFF) bypasses heated air from the heater muff into the engine
compartment. Rotating the control clockwise opens the door in the
heater box allowing heated air to enter the mixing plenum.
Cabin Cooling Control
The amount of cooling air allowed into the air mixing plenum is
controlled by rotating the cabin cool control, located outboard of the
cabin air selector. The control is mechanically linked to a butterfly
valve at the fresh air entrance to the mixing plenum. Rotating the
control full counterclockwise shuts down cooling airflow to the mixing
plenum from the fresh air inlet in the right wing root. Rotating the
control clockwise opens the butterfly allowing fresh cooling air to enter
the mixing plenum. Rotating the knob to the full clockwise (COLD)
position provides maximum cooling airflow to the mixing plenum.
P/N 13772-001 7-77
Revision A10