Daikin E Series, Service Manual

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Troubleshooting for Outdoor Unit SiAU18-715
362 Troubleshooting
7.4 Compressor Motor Lock
Remote
Controller
Display
E5
Applicable
Models AII outdoor unit models
Method of
Malfunction
Detection Inverter PCB takes the position signal from UVW line connected between the inverter and
compressor, and the malfunction is detected when any abnormality is observed in the phase-
current waveform.
Malfunction
Decision
Conditions This malfunction will be output when the inverter compressor motor does not start up even in
forced startup mode.
Supposed
Causes
„
Compressor lock
„
High differential pressure (0.5MPa or more)
„
Incorrect UVW wiring
„
Faulty inverter PCB
„
Stop valve is left in closed.
Troubleshooting
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Check the installation
conditions.
Is the stop valve
open?
Is the UVW wiring
normal?
Is high
differential pressure
starting? (0.5MPa or
more)
Check and
see whether compressor
is short-circuited or
ground.
Are
inverter output
voltages the same for
3 phases?
Does
low or high
pressure vary even
instantaneously when
restarting
compressor?
Open the stop valve.
Connect correctly.
Remedy the cause.
Replace the compressor.
Replace the inverter PC
board (A1P).
Replace the compressor.
(Q0553)
NO
YES
YES
NO
NO
YES
NO
YES
YES
NO
YES
NO