2001 GMC Safari Owner's Manual - Page 159

BI-LEVEL: This setting brings in outside air and blows it out through the heater floor vents and the instrument panel vents. If you move the temperature knob between hot and cold, cooler air will come out of the upper vents while warmer air comes out of the floor vent. The air conditioning compressor may operate in this setting to cool the air. VENT: The air comes out at the vents on your instrument panel. The air conditioning compressor will not run in this position. Adjust the temperature knob for warmer or cooler air. HEATER: Most of the air comes out near the floor. The rest comes out from the defroster vents under the windshield and at the front side windows. BLEND: With this setting, the heated outside air comes out of both the heater vents and defroster vents. Adjust the temperature knob for warmer or cooler air. The air conditioning compressor may operate in this setting to dehumidify the air. DEFROST: This setting operates the defroster. Most of the air comes out near the windshield, with some going to the floor vents and front side windows. The air conditioning compressor may operate in this setting to dehumidify the air. Heating System If your vehicle does not have air conditioning, your heater controls will look like this. Fan Knob This control has four positions. To increase airflow, turn the knob toward HI. To decrease airflow, move it toward LO. Temperature Knob This knob is next to the fan knob. It controls the temperature of the air flowing into your vehicle. Turn the knob clockwise for warmer air. Turn the knob counterclockwise for cooler air. 3-3