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9.0 DIAGNOSTICS & TROUBLESHOOTING
Diagnostics
9.9 Service Analyzer Charts (cont.)
COMPRESSOR OVERHEATING - HIGH DISCHARGE TEMP (cont.)
SYMPTOM
POSSIBLE CAUSE
REMEDY
Short cycling of
compressor (cont.)
Low charge
Check system charge.
Low evaporator airflow
Dirty coil.
Dirty filter.
Duct too small or restricted.
Faulty internal overload
Replace compressor.
ELECTRICAL
SYMPTOM
POSSIBLE CAUSE
REMEDY
Voltage present on
load side of inverter
and compressor
won’t run
Communication failure from VSODC to inverter.
Check communications harness connectors and wire
continuity.
Compressor windings
Check for correct ohms.
187 - 252VAC
present at input to
inverter
Thermostat
Check for control voltage to contactor coil.
Compressor control circuit
High-pressure switch.
Low-pressure cut-out.
Ambient thermostat.
Stater heat is active.
Compressor timed off/on control or interlock.
No voltage at input
to inverter
Blown fuses or tripped circuit breaker
Check for short in wiring or unit.
Improper wiring
Recheck wiring diagram.
Improper voltage
High voltage
Wrong unit.
Power supply problem.
Low voltage
Wrong unit.
Power supply problem.
Wiring undersized.
Loose connections.
FLOODED STARTS
SYMPTOM
POSSIBLE CAUSE
REMEDY
Liquid in the com
-
pressor shell
Faulty stator heat circuit (compressor thermistor or
single leg output to compressor)
Replace compressor thermistor.
Check inverter for single leg output power and correct wiring.
Too much liquid in
system
Incorrect piping
Check piping guidelines.
Overcharge
Check and adjust charge.
