Thermo King T-1080S, Руководство по обслуживанию

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Refrigeration Diagnosis
Rapid cycl
ing between Cool and Heat
Unit cools i
n Heat and Defrost cycle
Unit heat
s in Refrigeration (Cool) cycle
High head pressure Low head pressure No head pressure High suction pressure Low suction pressure No suction pressure Unit operating in a vacuum Receiver sight glass
empty
Suction line fros
ting back
Unable to pump down system Unable to pull vacuum in low side Unable to hold vacuum in low side Noisy compressor Unit not refrigerating Unit not heating or defros
ting
Sym
p
to
m
Possible Causes
• • • • Overcharge of refrigerant
• • • • • • Shortage of refrigerant
• • • • • • No refrigerant
• Air through condenser too hot (ambient)
• Air flow through condenser restricted
• • • 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
• Compressor discharge check valve leaking
• • Scroll compressor seals leaking
• Too much compressor oil in system
• Faulty oil pump in compressor
• Loose compressor pulley
• Compressor bearing loose or burned out
• • • • • Broken discharge check valve 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
• • • Liquid refrigerant entering compressor
• • Restricted line on the low side