2001 Chevrolet Impala Owner's Manual - Page 172

Comfort Controls Manual Single Zone Climate Control If airflow seems very low when the fan knob is turned to the highest setting, regardless of the mode setting, your passenger compartment air filter (if equipped) may need to be replaced. See "Maintenance Schedule" in the Index. Temperature Knob The center knob on the control panel changes the temperature of the air coming through the system. Turn this knob toward red (clockwise) for warmer air. Turn it toward blue (counterclockwise) for cooler air. Mode Knob The right knob on the control panel has several settings to control the direction of the airflow: With this system, you can control the heating, cooling and ventilation in your vehicle. The system works best if you keep your windows closed while using it. Fan Knob The knob on the left side of the climate control panel regulates the fan speed. To turn the fan off, turn the knob to OFF. UPPER: This setting directs air through the instrument panel outlets. BI-LEVEL: This setting directs air two ways. Half of the air is directed through the instrument panel outlets. Most of the remaining air is directed through the floor vents and a small amount to the windshield defroster and side window outlets. 3-2