2002 Buick Rendezvous Owner's Manual - Page 226

Mode Buttons VENT: This button turns the air conditioning compressor on and off and changes the mode to upper. The words A/C OFF are shown in the display. Recirculation is not permitted when the compressor is off. The system will try to control the temperature automatically, but without the compressor. (Recirculation): Press this button (the recirculation symbol in the display will be lit) to recirculate the air inside of your vehicle and to limit the amount of outside air and/or odors entering the vehicle. Press this button again (the recirculation symbol will go off) to send outside air into your vehicle. Using this setting while trying to defrost or defog the windows will help clear the vents of moisture. When the defog, defrost or lower setting is selected, the system will automatically go to outside air mode. Operating the Heating/Ventilation/Air Conditioning (HVAC) system in the recirculation mode may cause fogging of the vehicle's windows when the weather is cold and damp. To clear the fog, switch the HVAC system to either the defog or defrost mode and increase the fan speed. To avoid refogging of the windows, operate the HVAC system in the outside air mode. Air Conditioning On very hot days, your vehicle will cool down more quickly and economically if you open the windows long enough to let hot, inside air escape. For all settings, adjust the temperature knob and fan speed as desired. To get maximum cooling or a quick cool-down on very hot days, press the recirculation button (the recirculation symbol in the display will be lit) and turn the temperature knob to the desired interior temperature. Then, select the mode to direct the air to the desired location. This setting should not be used for long periods of time because the air may become too cold and dry. Push the recirculation button again (the recirculation symbol will go off) to turn off recirculation. When the air conditioner compressor is on, you may sometimes notice slight changes in your vehicle's engine performance and power. This is normal. The system is designed to help fuel economy while it maintains the desired cooling level. The air conditioner removes moisture from the air, so you may sometimes notice water dripping from under your vehicle's engine compartment when it is idling or after it has been turned off. This is normal. 3-7