5-1
T-294-01
SECTION 5
TROUBLESHOOTING
CONDITION
POSSIBLE CAUSE
REMEDY/
REFERENCE
SECTION
5.1 UNIT WILL NOT START OR STARTS THEN STOPS
External power source OFF
Turn on
No power to unit
Start-Stop switch (ST) OFF or defective
Check
No power to unit
Circuit breaker (CB) tripped or OFF
Check
Modular transformer (TRANS) not connected
6.21
Circuit breaker (CB) OFF or defective
Check
Loss of control power
Control transformer (TR) defective
Replace
Loss of control power
Fuse (F3) blown
Check
Start-Stop switch (ST) OFF or defective
Check
Evaporator fan motor internal protector (IP) open
6.16
Loss of control power in
Condenser fan motor internal protector (IP) open
6.19
Loss of control power in
respective branch of control
Compressor internal protector (IP) open
6.8
p
circuit only
High pressure switch (HPS) open
5.7
Heat termination thermostat (HTT) open
Replace
Low line voltage
Check
Compressor hums, but does not
Single phasing
Check
Compressor hums, but does not
start
Shorted or grounded motor windings
6.8
Compressor seized
6.8
5.2 UNIT RUNS BUT HAS INSUFFICIENT COOLING
Compressor
Compressor valves defective
6.8
Abnormal pressures
5.7
Temperature controller malfunction
5.9
Refrigeration System
Evaporator fan or motor (EM) defective
6.16
Refrigeration System
Stepper motor suction modulation valve (SMV) malfunction 6.24
Condenser Pressure Transducer (CPT) defective
Check
Shortage of refrigerant
6.7
5.3 UNIT OPERATES LONG OR CONTINUOUSLY IN COOLING
Container
Hot load
Normal
Container
Defective box insulation or air leak
Repair
Shortage of refrigerant
6.5/6.7
Evaporator coil covered with ice
5.6
Evaporator coil plugged with debris
6.14
Evaporator fan(s) rotating backwards
6.16/6.17
Defective evaporator fan motor/capacitor
6.16/6.17
Refrigeration System
Air bypass around evaporator coil
Check
Refrigeration System
Controller set too low
Reset
Dirty condenser
6.18
Compressor worn
6.8
Current limit (Code 32) set to wrong value
3.1.4
Stepper motor suction modulation valve (SMV) malfunction 6.24
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