GMC TopKick 2007 Owner's Manual page 156

To change the current mode, select one of the
following:
(Off): This setting turns the system off.
9
H
(Vent): This mode directs air to the instrument
panel vents.
)
(Bi-Level): This mode directs half of the air to
the instrument panel vents, then directs the
remaining air to the floor vents. Cooler air is
directed to the upper vents and warmer air to the
floor vents.
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(Floor): This mode directs most of the air to
the floor vents. Use this mode to send air to
the rear of the vehicle. Keep the area under the
front seats free of objects that could obstruct
airflow to the rear of the vehicle.
The mode knob can also be used to select the
defrost mode. For more information, see
"Defogging and Defrosting" later in this section.
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(Fan): Turn the left knob clockwise or
counterclockwise to increase or decrease the fan
speed. To increase airflow, turn the knob clockwise.
To decrease airflow, turn it counterclockwise. To
turn the fan off, turn the mode knob on the far right
counterclockwise to the off position.
156
Temperature Knob: Turn the middle knob located
clockwise or counterclockwise to increase or
decrease the temperature inside of your vehicle.
Turn the knob toward the red area for warmer air.
Turn the knob toward the blue area for cooler air.
If your vehicle has air conditioning, the controls will
look like this:
Vehicles With Air Conditioning
On hot days, open the windows to let hot inside
air escape; then close them. This helps to reduce
the time it takes for your vehicle to cool down.
It also helps the system to operate more efficiently.
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(Maximum Air Conditioning): Turn the
right knob to this setting for maximum cooling.
This setting puts the system in recirculation mode
and helps to maximize your air conditioner's
performance and your vehicle's fuel economy. This
setting also cools the air the fastest.