Thermo King 914 724, Manual

Page: 95 / 111

85
Refrigeration Diagnosis
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POSSIBLE CAUSES
• •
Overcharge of refrigerant
• • • • • • •
Shortage of refrigerant
• • • • • • • •
No refrigerant
•
Air through condenser too hot (ambient)
•
Air flow through condenser restricted (dirty)
• •
Air through condenser too cold (ambient)
• • •
Air in refrigerant system
•
Condenser fan blades bent or broken
•
Air short cycling around evaporator coil
• • • •
Air through evaporator restricted
• • • • • •
Evaporator needs defrosting
• •
Broken compressor belt
•
Compressor discharge valves leaking
• • •
Too much compressor oil in system
•
Loose compressor pulley
•
Compressor bearing loose or burned out
• • • •
Broken valve plate in compressor
• • • •
Expansion valve power element lost its charge
• • •
Expansion valve feeler bulb improperly mounted
• • •
Expansion valve feeler bulb making poor contact
• • • •
Expansion valve open too much
• •
Expansion valve closed too much
• • •
Expansion valve needle eroded or leaking
• • • •
Expansion valve partially closed by ice, dirt or wax