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Unit Description
26
High Pressure Relief Valve:
The high pressure
relief valve is designed to relieve excess pressure
within the refrigeration system. The valve is a
spring-loaded piston that lifts off its seat when
refrigerant pressure exceeds 500 psig (3447 kPa).
The valve will reseat when the pressure drops to
400 psig (2758 kPa). The valve could possibly
leak refrigerant after it has relieved excess
pressure. Tapping the valve lightly may help the
valve reseat and seal properly. The valve is
non-repairable and requires no adjustment. If the
valve fails to reseat properly, remove the
refrigerant charge and unscrew and replace the
valve.
The high pressure relief valve is located on a high
pressure line near the condenser. Its location is
such that when the pressure is expelled from the
valve, it would be directed away from anyone
servicing the unit.
Low Oil Level Switch:
The low oil level switch
closes if the oil drops below a certain level. If it
stays closed for a specified time, the
microprocessor will shut the unit down and record
alarm code 66 (normal code when changing oil).
Preheat Buzzer:
The preheat buzzer sounds when
the CYCLE-SENTRY system energizes the glow
plugs.
Compressor High Temperature Cutout Switch:
This switch is in series with the high pressure
cutout. If compressor discharge temperature
exceeds the switch setpoint, it opens the 8H
circuit and stops the unit.
Water Temperature Sensor:
This sensor provides a
WTS input to the microprocessor interface board.
if the engine coolant temperature is too high, the
controller stops the unit and records an alarm.
Oil Pressure Sensor:
This sensor provides an OPS
input to the microprocessor interface board. If the
oil pressure remains too low, the controller stops
the unit and records an alarm.
Unit Operation
Pretrip Inspection (Before Starting
Unit)
The following pretrip inspection should be
completed before starting the unit and loading the
trailer. While pretrip inspection is not a substitute
for regularly scheduled maintenance inspections,
it is an important part of the preventive
maintenance program designed to head off
operating problems and breakdowns before they
happen.
Fuel:
The diesel fuel supply must be adequate to
guarantee engine operation to the next check
point.
Engine Oil:
The engine oil level should be at the
FULL mark with the dipstick not routed
(threaded) into the oil pan. Never overfill.
Coolant:
The engine coolant must have antifreeze
protection to -30 F (-34 C). Check and add coolant
in the expansion tank.
Battery:
The terminals must be clean and tight.
Electrolyte should be at the full mark.
Belts:
The belts must be in good condition and
adjusted to the proper tensions. If a belt has cracks
more than 50% of the belt height, it is very close
to failure and should be replaced.
Poly-v belts (compressor/alternator/motor) must
be fully seated in their pulleys. Improper
operation of this belt will produce rapid damage
and belt shredding failure.
Electrical:
The electrical connections should be
securely fastened. The wires and terminals should
be free of corrosion, cracks or moisture.
CAUTION: Do not remove expansion
tank cap while coolant is hot.
CAUTION: Do not add Red Extended Life
Coolants to cooling systems using Green
or Blue-Green coolants. Do not add Green
or Blue-Green coolants to cooling systems
using Red Extended Life Coolants. See
“ELC (Extended Life Coolant)” on
page 62 for more information.
Summary of Contents for 919180
Page 4: ...4...
Page 10: ...Table of Contents 10...
Page 32: ...Unit Description 32 Unit Photographs Figure 3 Front View Figure 4 Back View AJA584 AJA585...
Page 33: ...Unit Description 33 Figure 5 Left Side View Figure 6 Right Side View AJA586 AJA58...
Page 35: ...Unit Description 35 Figure 8 North American Power Receptacle Box AJA58...
Page 38: ...Unit Description 38...
Page 58: ...Electrical Maintenance 58...
Page 66: ...Engine Maintenance 66 Figure 37 Fuel and Oil System Components...
Page 84: ...Engine Maintenance 84...
Page 96: ...Refrigeration Maintenance 96...
Page 118: ...Hilliard Clutch Maintenance 118...
Page 136: ...Cycle Diagrams 136...
Page 140: ...Wiring and Schematic Diagrams Index 140...
Page 141: ...141 Truck S Model SR 30 Schematic Diagram Page 1 of 2...
Page 142: ...142 Truck S Model SR 30 Schematic Diagram Page 2 of 2...
Page 143: ...143 Truck S Model 30 Units with P T Wiring Diagram Page 1 of 2...
Page 144: ...144 Truck S Model 30 Units with P T Wiring Diagram Page 2 of 2...
Page 145: ...145 Truck S Model 50 Schematic Diagram Page 1 of 2...
Page 146: ...146 Truck S Model 50 Schematic Diagram Page 2 of 2...
Page 147: ...147 Truck S Model 50 Units with P T Wiring Diagram Page 1 of 2...
Page 148: ...148 Truck S Model 50 Units with P T Wiring Diagram Page 2 of 2...