Panasonic 4CW056MA01 Applications Manual page 29

Problem
Flooded-start
Piping
Abnormal running
noise
Compressor
High discharge
pressure
Low discharge
pressure
Compressor runs
but with poor
cooling effect
High suction
pressure
Low suction
pressure
Compressor
Frosted/dew
Smelly
Check Point
During off cycle, liquid refrigerant migrates to the compressor and
mixed with lubricant oil
Refrigerant overcharged
Resonance vibration occurs
Electromagnetic noise of motor
Lack of oil in the compressor
Worn or broken components inside of compressor
Contaminations mix in compressor
Reverse rotation of compressor
Feet of the compressor touch the system base
Non-condensable gas(or air) mixed in system
Refrigerant overcharged
Condenser fan failure
Dirty or blockage of condenser coil
Short air cycle
Insufficient refrigerant in system
Leakage of refrigerant
Too low ambient temperature
Large air flow through condenser
Liquid refrigerant flooding back
Worn compressor
Too high of heat load
Poor heat insulation
Too low superheat setting of expansion valve
Malfunction of expansion valve
Incorrect installation of temperature sensor
Defect compressor
Too low of heat load
Insufficient refrigerant charge
Dirty or iced evaporator coil
Blockage of expansion device
Blockage of refrigeration circuit or leakage of refrigerant
Improper size of expansion valve
------
Too low heat load
Large amount of refrigerant leakage
------ Overheating of electronic components
Overheating of compressor shell
Probable Causes
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