2--3
©
2015 Mobile Climate Control
T-367Re v. 05/2015
2.4
BASIC OPERATING INSTRUCTIONS
When the engine is running, press the On/Off
button on display.
2.4.1 Display
When the unit is ON, the display shows the interior
set point temperature, current blower speed setting,
mode selection and Interior/Exterior temperatures.
2.4.2 Interior Set Point Temperature Control
Press the UP (Red) or Down (Blue) keys to set the
desired interior temperature.
The temperature can be adjusted between 62
°
F (16
°
C) and 82
°
F (28
°
C).
2.4.3 Blower Speed Setting
Blower speed operation will be set for high or low
speed operation automatically through software, or
can be set through manual switches provided at the
driver area.
2.4.4 Mode Selection Descriptions
a.
Auto
- In the auto mode, the ECC node will adjust
the individual components to maintain the desired
set point temperature.
In the auto mode, the evaporator fans will operate
in an “Ultra” high speed to achieve desired set
point faster, when the interior temperature is
greater than 5.4°F (3°C), from desired set point.
In the auto mode, the A/C system will continue to
operate when set point is reached, and will ener
gize the boost pump and de-energize the heat
solenoid valve to maintain temperature. This is re
ferred to as Reheat mode, to provide additional de
humidification of interior space.
The reheat mode will be disabled if the outside am
bient air temperature is below 43
°
F (6.1
°
C).
b.
Cooling
- In the cooling mode, the Compressor,
condenser fans and evaporator fans will be ener
gized. The heater solenoid valve will be energized
(closed), to provide full cooling.
The compressor and condenser fans will be de-en
ergized 2 degrees F below set point. The evaporat
or fans will continue to operate to circulate interior
air.
c.
Heating
- In the heating mode, the compressor
and condenser fans will remain de-energized.
Evaporator fans will be energized. The boost
pump will be energized,and the heat solenoid valve
will be de-energized (opened), to allow engine
coolant to flow through the heater coils. If the in
terior temperature is more than 5
°
F (3
°
C) below
set point, the floor blowers (if equipped) will also
be energized.
d.
Defrost
- In the defrost mode, the boost pump
will be energized to provide engine coolant flow to
the drivers unit to allow defogging of the wind
shield.
Defrost Override
- In the event the main HVAC
system is “OFF”, the ability of the OEM to
provide a signal to the controller to energize the
Boost Pump to provide engine coolant flow for
the Drivers Defroster is provided.
e.
Vent
- In the vent mode, the evaporator blowers
are operated to circulate air in the bus.
2.4.5 Capacity Control “Ladder” Diagrams
Ladder diagrams showing system operational
control logic for Auto/ Cool (Reheat system), and
Heat, can be seen in Figure 2-3.