2001 Chevrolet Lumina Owner's Manual - Page 130

Air Conditioning On very hot days, open the windows long enough to let hot, inside air escape. This reduces the A/C compressor load, which should help fuel economy. For quick cool-down on very hot days, use MAX with the temperature control all the way in the blue area. If this setting is used for long periods of time, the air in your vehicle may become too dry. For normal cooling on hot days, use A/C with the temperature control in the blue area. The system will bring in outside air and cool it. On cool but sunny days, the sun may warm your upper body, but your lower body may not be warm enough. You can use BI-LEVEL with the temperature control in the middle. The system will bring in outside air and direct it to your upper body, while sending slightly warmed air to your lower body. You may notice this temperature difference more at some times than at others. Heating On cold days use FLOOR with the temperature control all the way in the red area. The system will bring in outside air, heat it and send it to the floor ducts. If your vehicle has an engine coolant heater, you can use it to help your system provide warm air faster when it's cold outside -- 0_F (-18_C) or lower. An engine coolant heater warms the coolant your engine and heating system use to provide heat. See "Engine Coolant Heater" in the Index. Defogging and Defrosting Your system has two settings for clearing the front and side windows. To defrost the windows quickly, use DEFROST with the temperature knob all the way in the red area. To warm passengers while keeping the windows clean, use DEFOG. 3-4