140
MUL
TI V 5 Outdoor Unit Service Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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ERROR CODES
Please refer to the Safety Precautions on pages 4-7 for more detail to prevent injury or death regarding the operation and service
troubleshooting of the Multi V product.
WARNING
Error No. 05
Error No.
Description
Details
Causes
05
Communication
error between out-
door unit PCB and
indoor unit PCB.
Indoor unit PCB is not receiving communica-
tions signal from outdoor unit PCB for more
than 5 minutes. Check indoor unit PCB for
issues.
1. Auto addressing has not been performed
properly.
2. Communication cable is not connected.
3. Communication cable is short circuiting.
4. Indoor unit communication circuit error.
5. Outdoor unit communication circuit error.
6. Not enough physical distance between pow-
er wiring and communication cables.
7. T-phase line disconnection.
Do all the indoor units
display error code CH05?
Is the outdoor unit
PCB LED blinking?
Yes
Yes
No
Is the main circuit breaker OFF?
No
Is the power supply at
the outdoor unit terminal
block correct?
Power supply cable is not connected properly.
There is a problem with the main power supply.
Yes
No
Yes
No
Outdoor unit PCB is malfunctioning.
Check, then replace.
Reconnect communication cable.
No
Yes
Indoor unit PCB is malfunctioning.
Check, then replace.
Communication from the indoor unit is normal if voltage
fluctuation (-9V ~ +9V) exists (when checking DC voltage of the
communication terminal between the indoor and outdoor units).
After auto addressing, is
the correct number of indoor
units connected displayed?
No
END
If the DC voltage between communication terminal A, B
of indoor unit fluctuates within -9V ~ +9V, then the
communication from the outdoor unit is normal.
Check the insulation of the inverter
compressor; replace if necessary.
Check the capacity of main circuit
breaker; replace if necessary.
Check the T-phase connection.
If the above are operating correctly,
turn on main circuit breaker.
Check and replace the outdoor unit
PCB.
Check and replace TRANS.
Replace the PCB of indoor unit after
error is displayed.
Reconnect after checking the
communication cable of the indoor
unit that displays the error.
Check if the
communication cable is
properly connected
to indoor / outdoor unit
terminal blocks?
Yes
Images here are representative
of system components. Actual
component appearance depends
on model and system type.
See also Error Code No. 237:
RS-485 Communication Error
Between Indoor Unit and Outdoor
Unit, and Error Code No. 238:
Outdoor Unit PCB Communication
Error Between Indoor Unit and
Outdoor Unit.