Hummer 2008 H2 - Manual (Page 176)

The recirculation mode cannot be used with floor,
defrost, or defogging modes. If you try to select
recirculation in one of those modes, the indicator will
flash three times and turn off. The air conditioning
compressor will also come on when this mode is
activated. While in recirculation mode the windows
may fog when the weather is cold and damp.
To clear the fog, select either the defog or defrost
mode and increase the fan speed. Recirculation
mode can be turned off by pressing the button again,
or turning off the engine.
AUX: For vehicles with the rear heat and air
conditioning controls. Press the AUX button to turn
the rear climate control system on or off. See Rear
Air Conditioning and Heating System and Electronic
Climate Controls on page 3-29.
;
(Outside Air, If Equipped): Press this button
to turn on the outside air mode. When this mode
is selected, air from outside the vehicle circulates
throughout the vehicle. An indicator light on the button
comes on to show that it is activated. The outside
air mode can be used with all modes, but it cannot
be used with the recirculation mode.
Air Conditioning
#
(Air Conditioning): Press this button to turn the
air conditioning (A/C) compressor on and off. When air
conditioning is selected, an indicator light comes on
to show that the air conditioning has been activated.
Pressing this button when the outside temperature is
too cool for air conditioning will make the air conditioning
indicator flash three times and then turn off to let you
know the air conditioning mode is not available. If the
air conditioning is on and the outside temperature
drops below a temperature which is too cool for
air conditioning to be effective, the air conditioning
light turns off to show that the air conditioning mode
has been canceled.
On hot days, open the windows long enough to let
hot inside air escape. This helps to reduce the time
it takes for your vehicle to cool down. It also helps the
system to operate more efficiently.
The air conditioning system removes moisture from the
air, so a small amount of water might drip underneath
the vehicle while idling or after turning off the engine.
This is normal.
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