1999 Chevrolet Silverado 1500 Pickup Owner's Manual - Page 163

yellowblue Heater and Air Conditioning Comfort Controls (If Equipped) Mode Knob The right knob on the control panel allows you to choose the direction of air delivery. PANEL: This setting directs the air through the instrument panel outlets and the center floor console (if equipped). BI-LEVEL: Air is delivered through the instrument panel outlets and center floor console outlets (if equipped) as well as the heater floor outlets. The air flow can be divided between PANEL and HEATER depending upon where the knob is placed between the settings. Pressing the A/C button while in this mode causes cooler air to come out of the instrument panel outlets and center floor console outlets (if equipped) and warmer air to come out of the heater floor outlets over a wider range of temperature knob positions. HEATER: This setting directs most of the warmed air through the heater floor outlets and center floor console outlets (if equipped), as well as some air through the windshield defroster outlets and side window defroster outlets. If air from the center floor console outlets is not desired, turn the vents off at the console. Fan Knob The knob on the left side of the heating and air conditioning 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 counterclockwise to OFF. Temperature Knob The middle knob on the control panel lets you select the relative temperature of the air flowing into the passenger area of your vehicle. Turn the knob clockwise toward the red area for warmer air. Turn the knob counterclockwise toward the blue area for cooler air. 3-3