2-55
CONTROLS
CONTROL PANEL OPERATION
AIR CONDITIONER
(1) PWR
Powers vehicle Heater-A/C control system
on or off. The LED numeric display is
illuminated when the unit is turned on. The
display will show the current set point
temperature.
(2) TEMPERATURE UP /DOWN
Increments the set point temperature up or
down. The system will control the electronic
water valve and/or the A/C compressor
clutch to hold the cab temperature as closely
as possible to the set point temperature.
(3) FAN UP/ DOWN
Overrides the automatic fan speed control
(AUTO) feature. Increments fan speed up or
down in 11 steps. The digital display
indicates the fan speed setting as a
percentage or “HI” when maximum fan
speed is reached or “LO” when the minimum
fan speed is reached. The speed setting will
be shown for 5 seconds before returning to
the set point temperature display. The fan
speed is maintained until it is changed or if
the AUTO key is depressed.
(4) ECON (Economy Mode)
When depressed, locks out the A/C function.
The control used only fresh air, fan speed,
and water valve control to maintain the set
point temperature. Depressing the ECON
key will return the system back to normal
operation. An indicator light on the digital
display indicates when this mode is active.
Note that defrost (DEF) overrides the ECON
function.
(5) AUTO
Places the system in a fully automatic
temperature control mode including fan
speed. A panel indicator light indicates when
this mode is active. The system will adjust
the blower fan speed to the lowest setting
necessary to maintain the cab temperature
at the displayed set point temperature.
(6) MODE (°C/°F)
Toggles the display units between degrees
Celsius and degrees Fahrenheit. The display
will show the units selected.
(7) DEF (Defrost icon)
Positions the fresh /recirc air door to the
fresh position and turns on the A/C
compressor clutch for dehumidification. A
panel indicator light indicates when this
mode is active. Note that selecting defrost
may override previous setting for ECON or
FRESH. This will be indicated by the state of
the ECON and FRESH key indicator lights.
When the defrost mode is de-selected, the
system will return to previously selected
modes.
(8) FRESH
This key toggles the fresh or recirculation air
modes. When the FRESH mode is enabled,
outside air is allowed into the vehicle. A panel
indicator light indicates when this mode is
active. Note that the defrost mode (DEF) will
override the FRESH function and enable the
fresh air mode.