Thermo King Precedent S-600, Operator'S Manual

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Unit Description
32
Operate the unit in high speed cool for approximately 15
minutes to stabilize operating conditions and temperature
before attempting to check the refrigerant.
NOTE: If the ball floats, there is sufficient refrigerant in the
unit for that load at that particular trailer temperature. This
test does not determine if the unit contains a full charge or an
overcharge of refrigerant.
Unit Protection Devices
Coolant Level Switch: The coolant level switch closes if
the coolant level drops below an acceptable level. If it stays
closed for a specified time, the microprocessor records alarm
code 37.
Engine Coolant Temperature Sensor:
The microprocessor uses the engine coolant temperature sensor
to monitor the engine coolant temperature. If the engine
coolant temperature rises above an acceptable level, the
microprocessor records alarm code 41 and possibly 18. The
microprocessor might also shut the unit down.
High Pressure Cutout Switch: The high pressure cutout
switch (HPCO) is located on the compressor discharge
manifold. If the compressor discharge pressure becomes
excessive, the switch opens the circuit to the run relay to stop
the unit. The microprocessor will record Alarm Code 10.
High Pressure Relief Valve: This valve is designed to
relieve excessive pressure in the refrigeration system. It is
located on the receiver tank. If the high pressure relief valve
opens, much of the refrigerant will be lost. Take the unit to a
Thermo King dealer if this occurs.