28
D How to check miswiring and serial signal error
Turn the power supply OFF.
Is there rated voltage in the power supply?
Yes
No
Check for incorrect indoor-outdoor connecting wiring.
Check the power supply.
A
Is there rated voltage between outdoor terminal block S1 and S2?
Check for miswiring, broken wires, and loose wire
connection between the power supply and outdoor
terminal block S1 and between the power supply and
outdoor terminal block S2.
Wait for 2 or more minutes after the power supply is turned on.
Touch S2 and S3 with tester probes and start the emergency operation.
When the emergency operation starts, does the rated voltage occur for 2 sec-
onds between indoor terminal block S2 and S3?
No
No
No
Was the indoor unit ever connected to the Multi
(MXZ) series and operated (turned on)?
The connection information to the Multi series is
stored in the indoor unit. Refer to “Deleting the
memorized abnormal condition” described in 11-2.1
to clear the error history. When the error history is
being cleared, the connection information also will
be initialized. The indoor unit will be compatible with
a low-standby-power model after initialization.
OK
Yes
B
Turn the power supply ON.
Yes
Turn OFF inverter-controlled lighting equipment.
Turn OFF the power supply and then turn ON again.
Press EMERGENCY OPERATION switch.
•
•
•
A
Is serial signal
error indicated 6
minutes later?
B
Yes
Reinstall either the unit or the light
away from each other.
Attach a
fi
lter on remote control
receiving section of the indoor unit.
•
•
No
NOTE:
Refer to the outdoor unit service manual.
Replace the indoor electronic
control P.C. board.
Does the indoor OPERATION
INDICATOR lamp (upper) blink
continuously 6 minutes after the
emergency operation starts?
No
Does DC (10 V or more) occur
between L68A and L68B on the
relay P.C. board?
Yes
Does the outdoor LED blink 6
times?
Yes
Replace the relay P.C. board. 1
No
Does DC (more than 0 V) occur
between indoor terminal block S2
and S3?
Yes
Replace the inverter P.C. board. 1
No
Turn the power supply OFF.
Start the emergency operation.
No
Repair has been completed.
Replace the inverter P.C. board
and the relay P.C. board. 1
1.
Electric charge may remain immediately
after the power supply is turned OFF.
Perform the procedure after 3 minutes.
Replace the inverter P.C. board
and the relay P.C. board. 1
Turn the power supply ON.
Does the indoor OPERATION
INDICATOR lamp (upper) blink
continuously 6 minutes after the
emergency operation starts?
Yes
No
Replace the indoor electronic
control P.C. board.
Yes
Replace the inverter P.C. board
and the relay P.C. board. 1
Yes
OBH634
