2004 GMC Envoy Owner's Manual - Page 148

6(Floor): This mode directs most of the air to the floor outlets. Some air also comes out of the defroster and side window outlets. The recirculation button cannot be selected in floor mode. #A/C (Air Conditioning): h (Recirculation): Press this button to manually turn the air conditioning system on or off. When the system is on, the system will automatically begin to cool and dehumidify the air inside of your vehicle. If you select air conditioning off while in front defrost or defog mode, the air conditioning off symbol will flash to let you know this option is not allowed. You may notice a slight change in engine performance when the air-conditioning compressor shuts off and turns on again. This is normal. A/C OFF (Air Conditioning Off): When you turn the air conditioning off, the words A/C OFF will appear on the display. When the air conditioning is selected or in AUTO mode, the system will run the air conditioning automatically. Press this button to turn recirculation mode on or off. When this button is pressed, an indicator light in the button will also come on to let you know that it is activated. Recirculation mode is used to recirculate the air inside of your vehicle. Use this mode to help prevent outside odors and/or dust from entering your vehicle or to help cool the air inside of your vehicle more quickly. Recirculation mode can be used with vent and bi-level modes, but it cannot be used with floor, defog or defrost modes. If the weather is cold and damp, the system may cause the windows to fog while using recirculation mode. If the windows do start to fog, select defog or defrost mode. 3-28