Cadillac 2000 DeVille Owner's Manual page 182

DEFROST: Press this button to quickly remove
fog or frost from the windshield. This setting sends most
of the airflow to the windshield with only a small
amount to the floor outlets.
FAN SPEEDS: Press the AUTO. At this setting,
the fan speed is automatically controlled. If it is cold
outside, the blower may not run in the maximum high
fan speed right away. The system checks the
temperature of the engine coolant to assure it is warm
enough to provide heat. When the engine coolant is
warm, the controller allows the fan to gradually increase
to a higher speed. This prevents cold air from blowing
into the passenger compartment.
OFF: Press the knob to turn the system off. Fresh
air will continue to flow through the vehicle, and the
system will try to maintain the previously set
temperature. The outside temperature will show on
the display when the system is OFF.
AC: Press this button to turn the air conditioning on and
off. The system will cool and dehumidify the air inside
the vehicle. In the AUTO mode the air conditioning
compressor only operates when the system determines it
is needed. The display will show A/C OFF when the air
conditioning is off.
RECIRCULATION: Press this button to limit the
amount of fresh air entering your vehicle. This is helpful
when you are trying to cool the air quickly or limit odors
entering your vehicle. In the AUTO mode, the system
will use recirculation as necessary to cool the air.
Pressing the recirculation button will change the
operation to a manual mode and the air will recirculate
-
non stop. Press this button again to turn off the
recirculation feature.
If you notice the windows fogging, press the
recirculation button to exit the recirculation mode.
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