1999 Pontiac Montana Owner's Manual - Page 204

yellowblue Heating Turn the temperature knob clockwise (toward the red area) to warm the air. In the LOWER mode, outside air will be brought in and sent through the floor outlets. The heater works best if you keep your windows closed while using it. The BI-LEVEL setting is designed for use on sunny days when the air is only moderately warm or cool. On days like these, the sun may adequately warm your upper body, but your lower body may not be warm enough. For the best results, turn the temperature control knob to the middle position, and then adjust it for comfort. If you have the optional engine coolant heater and use it during cold weather, 0_F (-18_C) or lower, your heating system will provide heat more quickly because the engine coolant is already warmed. See "Engine Coolant Heater" in the Index. Defogging and Defrosting To rapidly defrost the windshield, turn the temperature control knob all the way clockwise (to the red area) and turn the mode knob to DEFROST. Adjust the fan to the highest speed. To keep the windshield clear and bring in heated air through the heater ducts, turn the mode knob to DEFOG. When the temperature outside is above freezing, the air conditioner compressor will run in these settings to help remove moisture from the air. Your vehicle is equipped with side window defogger vents located on the top of the instrument panel. For additional side window defogging, turn the mode knob to the BI-LEVEL setting and adjust the fan to the highest speed. Aim the side vents on the instrument panel toward the side windows. For increased airflow to the side vents, close the center vents. 3-4