Chevrolet 2001 Express Van Owner's Manual page 148

A/C: This setting is used for normal cooling on hot
days. It cools outside air and directs it through the
instrument panel outlets.
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BI LEVEL A/C: This setting divides airflow
between the heater floor vents and instrument panel
vents. The air conditioning compressor will cycle
continuously in this setting as long as the outside air
temperature is warm enough to activate the compressor.
VENT: This setting directs air through the
instrument panel vents.
HEAT: This setting directs air through the heater
floor vents. It is useful for cold weather.
HEAT/DEFOG: This setting divides airflow
between the heater floor vents and the windshield. In the
blended position, the air conditioning compressor is
automatically activated to dehumidify the air.
DEFROST: This setting directs air through the
windshield defroster vents. It is useful when you have
fog or ice on the windshield.
3-4
Rear Heater (Without Air Conditioning)
(If Equipped)
If you have a rear heater (without rear air conditioning),
the control is located on the instrument panel.
To increase and decrease the flow of heated air to the
rear floor vents, turn the thumbwheel marked REAR
HEAT to the speed you want.
The thumbwheel has three speed positions. To increase
the flow of heated air, turn the thumbwheel toward
HIGH. To turn the fan off, turn the control to OFF.