Thermo King 098916, Руководство по обслуживанию

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Diagnosis: Troubleshooting, Status Messages, Alarm Codes
156
Troubleshooting Mechanical Problems
Condition Possible Cause Remedy
Compressor does not operate—
no amperage draw Controller on; unit start sequence still
timing Wait up to 2 minutes for compressor
start-up
No power to unit (condenser and
evaporator fans do not operate)
Locate fault and repair: power
source, power plug, CB1 main
circuit breaker, motor contactor,
motor terminals, motor
Open in 29 Vac control circuit
Check fuses and On/Off switch.
Replace or repair as required
Container temperature does not
demand compressor operation
Adjust controller setpoint
Compressor contactor inoperative Replace compressor contactor
No output signal from controller
Diagnose and replace main relay
board or controller
Unit on defrost
Turn Unit On/Off switch Off and then
On again
Detective high pressure or low
pressure cutout switch
Replace defective switch
High condenser head pressure
causing high pressure cutout Check refrigeration system and
correct fault
Defective compressor Replace compressor
Controller shut unit down on
Compressor Over Temperature
Let compressor cool and controller
will reset automatically. Check vapor
injection valve and compressor
temperature sensor
Compressor motor internal thermal
overload protection open
If compressor contactor is
energized, wait 60 minutes for
protector to cool and reset.
Compressor does not operate—
excessive amperage draw or
intermittent cycling on overload Rotating scroll stuck Replace compressor
Seized or frozen compressor bearings Replace compressor
Improperly wired
Check/correct wiring against wiring
diagram
Low line voltage
Check line voltage — determine
location of voltage drop
Contacts in compressor contactor not
closing completely Check by operating manually.
Repair or replace.
Open circuit in compressor motor
winding
Check motor stator connections.
Check stator winding for continuity.
If open, replace compressor
Defective compressor motor internal
thermal overload protector Replace thermal overload protector
or compressor
Refrigerant overcharge or high side
restriction causing cycling on high
pressure cutout Check for restricted filter drier,
in-line filter or high side; or
refrigerant overcharge
Inefficient condenser operation
causing cycling on high pressure
cutout
Check condenser airflow,
condenser fan motor, fan blade,
condenser grille, condenser coil
temperature sensor, water pressure
switch (option), water flow rate
(option) and water-cooled
condenser-receiver tank (option)