ELECTRICAL SYSTEMS - CHASSIS — 9
206
2008 IMPERIAL
MAX A/C -
Recirculated air is
drawn from the passenger area and
discharged through the dash louvers.
A/C -
Fresh air is drawn from outside
into the system and discharged
through the dash louvers.
VENT -
Fresh air is drawn in and
discharged throughout the dash.
OFF -
The blower motor does not
operate. The fresh air inlet door
will close, minimizing outside air
in
fi
ltration into the motorhome.
BI-LEVEL -
Fresh air is drawn in
and discharged through the dash and
the
fl
oor.
FLOOR -
Fresh air is drawn in and
discharged through the
fl
oor louvers.
MIX -
Fresh air is drawn in and
discharged through the
fl
oor and
defrost louvers. The A/C system
operates to dehumidify the
discharged air.
DEFROST -
Fresh air is
drawn in and discharged
through the defrost louvers.
The A/C system operates to
dehumidify the discharged air.
A/C Operation:
The A/C dash system will operate in all modes
except
BI LEVEL
,
FLOOR
and
OFF
. When
the Mode Control Knob is positioned in the
A/C
mode, fresh air is drawn through the front
air intake of the unit through the A/C coil. The
Mode Control Knob in the
MAX A/C
position
closes off a damper door to outside air and
recirculates air from inside the motorhome.
Select this position when maximum cold air is
desired or to keep outside air from entering the
motorhome.
Heat and Defrost Operation:
Set the Mode Control Switch to the
desired position.
Set the Temperature Control Switch to
the red zone.
Operating Tips & Hints
Air intake and discharge temperatures are
greatly affected by ambient temperatures and
relative humidity. A large amount of cooling
capacity is used to dehumidify as well as
cool air. After three to
fi
ve minutes of A/C
operations, discharged air temperature should be
approximately 20º to 30º F. cooler than the fresh
or recirculated air entering the A/C system.
Winter Use:
De-ice the windshield using the
DEFROST
mode.
Air will heat up faster with a slower
blower speed until normal operating
temperature ranges are reached.
Summer Use:
Close all windows and vents to hot,
humid outside air.
The recirculation blower provides quick
cool down.
Use a lower blower speed to produce
cooler air.
Heater:
The heater warms the air in the dash area.
Much like the refrigeration side of the system, a
liquid will be used in the process. This liquid is
the engine coolant. The coolant is passed from
the radiator to an electronic water valve. When
open, the water valve will allow the coolant to
fl
ow through the heater core. The heater core is
much like a miniature radiator. Air is drawn into
the system by a blower motor through the outside
recirculation door opening. Air is blown through
the A/C evaporator core and then through the
heater core. When the temperature control is
in the
WARM
position coolant
fl
ows through
the heater core. When the temperature is in the
COOL
position coolant
fl
ow bypasses the heater
core. In either position, the air
fl
ow is felt at the
discharge vents.
Electric Water Valve:
The water valve controls the water
fl
ow to
the heater core. A control module compares
the output voltage from the thermostat to the
feedback for the stepper motor of the water
valve. The control module then drives the motor
to within one-half volt of the control thermostat
voltage.
A/C
MAX
A/C
OFF
090273 - 277
