2006 Chevrolet Silverado 1500 Pickup Owner's Manual - Page 194

Climate Controls Climate Control System 9 (Off): If the fan is off, outside air will still enter the vehicle, and will be directed based on the position of the mode knob. The temperature can also be adjusted using the temperature knob. Temperature Knob The middle knob on the control panel lets you select the temperature of the air flowing into the passenger area. Turn the knob clockwise toward the red area for warmer air. Turn the knob counterclockwise toward the blue area for cooler air. Mode Knob The right knob on the control panel allows you to choose the direction of air delivery. Fan Knob The fan knob on the left side of the control panel adjusts the fan speed. To increase airflow, turn the knob clockwise. To decrease airflow, turn it counterclockwise. To turn the fan off, turn the knob to the off position. H (Vent): This setting directs the air through the instrument panel outlets. 3-20