2008 MERCEDES-BENZ R320 air condition

219 Controls in detail
Climate control
Air conditioning
The air conditioning is operational while
the engine is running and cools the interior
air to the temperature set by the operator.
In addition, the air conditioning dehumidi-
fies the interior air at outside temperatures
above 41°F (5° C) and helps prevent
window fogging.
Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified.Press button9 (page 210).
The indicator lamp on the button goes
out.
Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.
Press button9 (page 210) again.
The indicator lamp on the button
comes on.
The air conditioning uses the refrigerant
R134a. This refrigerant is free of CFCs
which are harmful to the ozone layer.
Residual heat and ventilation
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.
Activating
Switch off the ignition (page 39).
Press button9 (page 210).
The indicator lamp on the button
comes on.
iCondensation may drip out from underneath
the vehicle. This is normal and not an indication
of a malfunction.
Warning!G
If you turn off the cooling function, the inte-
rior air is not dried. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
!If the air conditioning cannot be turned on
again, this indicates that the air conditioning is
losing refrigerant. The compressor has turned
off.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Light Truck Center.
iHow long the system will provide heating
depends on

the coolant temperature

the battery voltage
Regardless of the temperature and air volume
set on the climate control panel, an interior tem-
perature is aimed at by 72°F (22°C) and the
blower runs on low speed to protect the vehicle
battery.

220 Controls in detail
Climate control
Deactivating
Press button9 (page 210) again.
The indicator lamp on the button goes
out.
Rear climate control*
The control panel is located on the rear of
the front center console.
Rear climate control panel
Activating rear climate control
Press buttonU.
The indicator lamp on the button
comes on. The air volume and air distri-
bution are adjusted automatically.
iThe residual heat is automatically turned off:

when the ignition is switched on

after about 30 minutes

if the coolant temperature is too low

if the battery voltage drops
iThe rear climate control panel is only avail-
able if your vehicle is equipped with seat heating
for the second-row seats* or Rear Audio
feature* (see separate COMAND System operat-
ing instructions).
1Rear climate control on
(automatic mode)
2Air distribution (directs air through
the center air vents)
3Rear air conditioning off
4Air distribution (directs air through
the footwells and side air vents)
5Right rear center air vent, adjustable
6Left rear center air vent, adjustable
iThe climate control must be switched on
(
page 221).
iThe temperature is adjusted according to
the settings for the front passenger side made
on the front climate control panel (
page 213).

225 Controls in detail
3-zone automatic climate control*
The automatic climate control is a 3-zone
intelligent automatic climate control
system. Your vehicle interior is divided
into 3 zones.With the help of a sun sensor, the
automatic climate control determines the
relation of the sun to the vehicle and auto-
matically adjusts the inside temperature
for each individual zone.The automatic climate control is oper-
ational whenever the engine is running. It
cools the vehicle’s interior according to the
angle and intensity of the sun’s rays, the
outside temperature and the selected tem-
perature. You can operate the automatic
climate control in either the automatic or
manual mode.
Nearly all dust particles, pollutants and
odors are filtered out before outside air
enters the passenger compartment
through the air distribution system.
Warning!G
When operating the automatic climate
control, the air that enters the passenger
compartment through the air vents can be
very hot or very cold (depending on the set
temperature). This may cause burns or frost-
bite to unprotected skin in the immediate
area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
controls (
page 224) to direct the air to air
vents in the vehicle interior that are not in
the immediate area of unprotected skin.Warning!G
Severe conditions (e.g. strong air pollution)
may require replacement of the filter before
its scheduled replacement interval.
A clogged filter will reduce the air volume to
the interior and the windows could fog up,
impairing visibility and endangering you and
others. Have a clogged filter replaced as
soon as possible at an authorized
Mercedes-Benz Light Truck Center.

226 Controls in detail
3-zone automatic climate control*
The air conditioning will not engage (no
cooling) if the A/C mode is deactivated
(
page 234).Deactivating the automatic climate
control system
Deactivating
Press button´ (page 224) until
the displaye (
page 224) is cleared.
The indicator lamp on the button
comes on.Reactivating
Press buttonU (page 224).
Warning!G
Follow the recommended settings for heat-
ing and cooling given on the following
pages. Otherwise the windows could fog up,
impairing visibility and endangering you and
others.
iIf the vehicle interior is hot, ventilate the in-
terior before driving off, see “Summer opening
feature” (
page 244). The automatic climate
control will then adjust the interior temperature
to the set value much faster.
Keep the air intake grille in front of the wind-
shield free of snow and debris.
Warning!G
When the automatic climate control system
is switched off, the outside air supply and
circulation are also switched off. Only
choose this setting for a short time.
Otherwise the windows could fog up,
impairing visibility and endangering you and
others.
iYou can also press button´
(
page 224) on the automatic climate control
panel.
If you press button| (
page 224) to reacti-
vate the automatic climate control system, the
defrosting mode is activated.

229 Controls in detail
3-zone automatic climate control*
Adjusting air volume
Five blower speeds are available.
Press button
to decrease or
buttonQ to increase air volume
(
page 224) to the desired level.
The indicator lamp on buttonU
goes out.
The automatic mode is switched off.
The selected blower speed appears in
the displaye (
page 224).
Front defroster
You can use this setting to defrost the
windshield, such as when it is iced up. You
can also use it to defog the windshield and
door windows.
Activating
Press button| (page 224).
The indicator lamp on the button
comes on.The automatic climate control switches to
the following functions automatically:

most efficient blower speed and
heating power, depending on outside
temperature

air flows onto the windshield and the
front door windows (side air vents must
be open)

the air conditioning compressor
switches on at outside temperatures
above approximately 41°F (5°C) for
air-drying
Adjustments
You can adjust the air volume and the
temperature when the front defroster is
switched on. The air flow will remain on the
windshield and front door windows.
iKeep this setting selected only until the
windshield or the door windows are clear again.

230 Controls in detail
3-zone automatic climate control*
Press button
to decrease or
buttonQ to increase the air volume
(
page 224) to the desired level.
The air volume decreases/increases to
the next lower/higher blower speed
and heating switches to the tempera-
ture that was set before the front de-
froster was switched on.
The indicator lamp on button|
goes out. The indicator lamp on
button9 comes on.
or
Turn temperature
control1and/or9 (
page 224)
slightly in any direction.
Heating switches to the temperature
that was set before the front defroster
was switched on.
The indicator lamp on button|
goes out. The indicator lamp on
button9 comes on.Deactivating
Press button| (page 224).
The indicator lamp on the button goes
out. Defrosting is turned off.
The previous settings are once again in
effect.Windshield fogged on the outside
Switch the windshield wipers on
(
page 59).
Press buttonU (page 224).
The indicator lamp on button U
goes out. Air volume and air
distribution are controlled separately
for each zone.
If the automatic air distribution and air
volume are switched off:
Press buttons8 and Y
(
page 224).
iThe air conditioning compressor remains on
even if the indicator lamp in button| goes
out. This helps to prevent the windshield from
fogging.
iTo switch off, you can also press
button´ orU (
page 224).
iKeep this setting selected only until the
windshield is clear again.

231 Controls in detail
3-zone automatic climate control*
Maximum cooling MAXCOOL
If the air distribution control as well as the
airflow volume control are set toU and
there is a high need for cooling, the
MAXCOOL function is activated.
“
MAXCOOL” appears in the display.
This provides the fastest possible cooling
of the vehicle interior (when windows and
tilt/sliding sunroof* or tilt/sliding panel*
are closed).
Air recirculation mode
Switch to air recirculation mode to prevent
unpleasant odors from entering the vehicle
from the outside (e.g. before driving
through a tunnel). This setting cuts off the
intake of outside air and recirculates the
air in the passenger compartment.Activating
Press button: (page 224).
The indicator lamp on the button
comes on.
Warning!G
Fogged windows impair visibility, endanger-
ing you and others. If the windows begin to
fog on the inside, switching off the air
recirculation mode immediately should clear
interior window fogging. If interior window
fogging persists, make sure the air
conditioning (
page 233) is activated, or
press button|.
iThe air recirculation mode is activated
automatically at high outside temperatures.
The indicator lamp on button:is not lit
when the air recirculation mode is switched on
automatically.
A quantity of outside air is added after
approximately 30 minutes.
If you have turned off the air conditioning
(
page 233) or the outside temperature is
below 41°F (5°C), the air recirculation mode will
not switch on automatically.
iTo cool the interior as fast as possible,
the automatic climate control automatically
switches to air recirculation. The indicator lamp
on button: is not lit when the system
switches to air recirculation automatically.

232 Controls in detail
3-zone automatic climate control*
Deactivating
Press button: (page 224).
The indicator lamp on the button goes
out.
At outside temperatures above
79°F (26°C) the system will not automati-
cally switch back to outside air. A quantity
of outside air is added after approximately
30 minutes.Air recirculation mode with
convenience closing and opening
feature
Vehicles with tilt/sliding sunroof*
Convenience closing:
Press button: for approximately
2 seconds.
The windows and/or tilt/sliding
sunroof will close. You can release
button: once the closing proce-
dure has begun. The windows and
tilt/sliding sunroof continue closing
until they are fully closed. The indicator
lamp on the button comes on. The air
recirculation mode is activated.
iThe air recirculation mode is deactivated
automatically

after 5 minutes if the outside temperature is
below approximately 41°F (5°C)

after 5 minutes if the air conditioning and
air-drying is turned off

after 30 minutes if the outside temperature
is above approximately 41°F (5°C)
Warning!G
Never operate the windows and tilt/sliding
sunroof* or tilt/sliding panel* if there is the
possibility of anyone being harmed by the
opening or closing procedure.
In case the procedure causes potential
danger:
Vehicles with or without tilt/sliding
sunroof*: The closing of the windows can be
immediately halted by pressing or pulling
the respective window switch. The closing of
the tilt/sliding sunroof* can be immediately
halted by moving the switch for the
tilt/sliding sunroof* in any direction.
The closing of the windows and the
tilt/sliding sunroof* can be reversed by
again pressing and holding the: button.
Vehicles with panorama roof*: The closing
of the windows and tilt/sliding panel* can
be immediately halted by releasing
the:button.
iA window, the tilt/sliding sunroof*, or the
tilt/sliding panel* will only return to its previous
position if it has not been moved to another
position using the respective window switch or
tilt/sliding sunroof* (or tilt/sliding panel*)
switch after it was closed with button:.