Beechcraft Baron G58 Pilot Operating Handbook page 476

The Air Conditioning System performs the following functions:
1. Cools cabin air temperature.
2. Establishes the humidity level of the cabin at a comfort-
able level.
3. Helps prevent fogging of windows.
4. Reduces dust and pollen particles from the cabin air.
OPERATION
Control of the refrigeration temperature cycle is done with an
electronic controlled thermostatic cycling sensor. The sensor
monitors evaporator temperature and cycles the engine driven
compressor to regulate the evaporator coil temperature and to
prevent the coil from "freezing up".
During operation during warm cabin temperatures the Auto-
matic Climate Control System operates in the air conditioning
mode, supplying cooled, dehumidified air to the ceiling console
vents. When the system switches to "heating" operation during
cool cabin temperatures, heated, outside air will be delivered
to the front and rear floor vents and the windshield based on
temperature conditions and the mode of operation settings.
Additionally, recirculated cabin air will be delivered to the ceil-
ing console vents, at a low blower setting, during the "heating"
mode operation. The blower speed of the air being delivered to
the ceiling console vents during "heating" mode operation is
not user selectable.
In the rare occurrence of a refrigeration "overpressure" condi-
tion, a high/low pressure trinary safety switch, located on the
receiver/dryer, will disengage the compressor to allow pres-
sures to return to a safe level. This same switch senses a low
pressure condition in the system and disengages the compres-
sor to prevent damage. The trinary safety switch automatically
resets once refrigerant pressures have returned to a safe level.
The Automatic Climate Control System can be left on in any
mode at the time of airplane shut-down and will resume the
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FAA Approved
Issued: March, 2017
P/N 58-590000-0091