2008 GMC Acadia Owner's Manual - Page 170

For quicker cool down on hot days, do the following: 1. Open the windows to let hot air escape. 2. Select the vent mode. 3. Select the air conditioner. 4. Select the coolest temperature. 5. Select the highest fan speed. 6. Close the windows after the hot air has escaped. 7. Once the vehicle's interior temperature is below the outside temperature, select recirculation mode for better cooling. This helps to reduce the time it takes for the vehicle to cool down. It also helps the system to operate more efficiently. Using recirculation for long periods of time may cause the air inside of the vehicle to become too dry. To prevent this from happening, after the inside of the vehicle has cooled, turn the recirculation mode off. The air conditioning system removes moisture from the air, so you might notice a small amount of water dripping underneath the front center and right rear of the vehicle while idling or after turning off the engine. This is normal. Defogging and Defrosting Fog on the inside of the windows is a result of high humidity (moisture) condensing on the cool window glass. This can be minimized if the climate control system is used properly. There are two modes to clear fog or frost from the windshield. Turn the right knob clockwise to select the defog or defrost mode. -(Defog): The defog mode is used to clear the windows of fog or moisture and warm the passengers. This mode directs air to the windshield, floor outlets, and side window vents. When you select this mode, the system turns off recirculation and runs the air conditioning compressor unless the outside temperature is less than 40°F (4°C). The recirculation mode cannot be selected while in the defog mode. Do not drive the vehicle until all the windows are clear. 0(Defrost): The defrost mode is used to remove fog or frost from the windshield more quickly. This mode directs most of the air to the windshield and side window vents and some to the floor vents. In this mode, the system will automatically force outside air into your vehicle. The recirculation mode cannot be selected while in the defrost mode. The air conditioning compressor will run automatically in this setting, unless the outside temperature is less than 40°F (4°C). Do not drive the vehicle until all the windows are clear. 3-28