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177
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
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Overcharge of refrigerant
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Shortage of refrigerant
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No refrigerant
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Air through condenser too hot (ambient)
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Air flow through condenser restricted
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Air through condenser too cold (ambient)
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Air in refrigerant system
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Condenser fan blades bent or broken
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Air short cycling around evaporator coil
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Air through evaporator restricted
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Evaporator needs defrosting
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Compressor discharge check valve leaking
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Scroll compressor seals leaking
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Too much compressor oil in system
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Faulty oil pump in compressor
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Loose compressor pulley
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Compressor bearing loose or burned out
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Broken discharge check valve in compressor
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Expansion valve power element lost its charge
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Expansion valve feeler bulb improperly mounted
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Expansion valve feeler bulb making poor contact
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Expansion valve open too much
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Expansion valve closed too much
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Expansion valve needle eroded or leaking
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Expansion valve partially closed by ice, dirt or wax
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Liquid refrigerant entering compressor
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Restricted line on the low side
Summary of Contents for T-1080S
Page 102: ...Engine Maintenance 101 Figure 182 Fuel and Oil System Components ...
Page 182: ...Index 181 Unit Options 23 W wiring 79 wiring diagrams index 182 ...
Page 184: ...183 Schematic Diagram Page 1 of 2 RELEASED 06 Jul 2015 13 52 47 GMT 7 ...
Page 185: ...184 Schematic Diagram Page 2 of 2 RELEASED 06 Jul 2015 13 52 47 GMT 7 ...
Page 186: ...185 Wiring Diagram Page 1 of 5 ...
Page 187: ...186 Wiring Diagram Page 2 of 5 RELEASED 06 Jul 2015 13 52 47 GMT ...
Page 188: ...187 Wiring Diagram Page 3 of 5 ...
Page 189: ...188 Wiring Diagram Page 4 of 5 RELEASED 06 Jul 2015 13 52 47 GMT ...
Page 190: ...189 Wiring Diagram Page 5 of 5 ...