43
9.0 DIAGNOSTICS & TROUBLESHOOTING
Diagnostics
9.9 Service Analyzer Charts (cont.)
COMPRESSOR OVERHEATING (cont.)
SYMPTOM
POSSIBLE CAUSE
CHECK OR REMEDIES
Short cycling of
compressor (cont.)
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Dirty coil
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Duct too small or restricted
Faulty run capacitor
Replace.
Faulty internal overload
Replace compressor.
Faulty Compressor
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Replace compressor and examine system to
locate reason.
ELECTRICAL
SYMPTOM
POSSIBLE CAUSE
CHECK OR REMEDIES
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on load side of
compressor
contactor and
compressor
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Compressor start components
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Run capacitor
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Internal overload
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on line side of
compressor
contactor only
Thermostat
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Compressor control circuit
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Ambient thermostat
Solid-state protection control or internal thermal sensors
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No voltage on line
side of compressor
contactor
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Improper voltage
High voltage
Wrong unit
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Wrong unit
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Wiring undersized
Loose connections
Single Phasing (3 phase)
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FLOODED STARTS
SYMPTOM
POSSIBLE CAUSE
CHECK OR REMEDIES
Liquid in the
compressor shell
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Too much liquid in
system
Incorrect piping
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Overcharge
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