6-5
62-10848
6.2.9
Cab Command Malfunction
Cab Command non-operational
Fuse open
Replace
Microprocessor malfunction
Replace
Microprocessor/Cab command cable
Check
6.2.10
No Evaporator Air Flow or Restricted Air Flow
Evaporator coil blocked
Heavy frost on coil
Check
Coil dirty
No or partial evaporator air flow
Evaporator fan loose or defective
Check
Evaporator fan rotating backwards
Check
Evaporator air flow blocked in refrigerated compartment
Check
Fan motor(s) malfunction
Replace
6.2.11
Expansion Valve
Low suction pressure with high
superheat
Low refrigerant charge
External equalizer line plugged
Repair
Broken capillary
Repair
Superheat setting too high
Low superheat and liquids lugging
in compressor
Superheat setting too low
External equalizer line plugged
Repair
Pin and seat of expansion valve eroded or held open by
foreign material
Fluctuating suction pressure
Improper bulb location or installation
Insulation missing from sensing bulb
Replace
Low superheat setting
High superheat
Expansion Valve setting
6.2.12
Malfunction Hot Gas Solenoid or Condenser Pressure Regulating Valve
Valve does not function properly
No power to valve
Check
Improper wiring or loose connections
Check
Valve improperly assembled
Coil or coil sleeve improperly assembled
Movement of plunger restricted due to:
a. Corroded or worn parts
b. Foreign material lodged in valve
c. Bent or dented enclosing tube
Valve shifts but refrigerant
continues to flow
Foreign material lodged under seat
Defective seat
6.2.13
Standby Compressor Malfunction
Standby compressor fails to start
Motor contactor defective
Replace
Motor Overload open
Check
Improper power supply
Correct
5-minute timer active
Check
Standby motor starts, then stops
Motor Overload open
Check
Table 6–2 Mechanical Indications (Continued)
Indication/Trouble
Possible Causes
Reference
Section