60
MXZ-5B
Upper or
left lamp of
OPERATION
INDICATOR
lamp (Indoor
unit)
Abnormal point
(Failure mode/protection)
LED indication
(Outdoor P.C.
board)
Condition
Remedy
Indoor/out-
door unit
failure mode
recall func-
tion
11-time
fl
ash
Communication error between
P.C. boards
Lighted 6 times Communication error occurs between the out-
door control P.C. board and outdoor power P.C.
board for more than 10 seconds.
• Check the connecting wire between the
outdoor control P.C. board and outdoor
power P.C. board .
—
The communication between boards protection
cut-out operates 2 consecutive times.
○
Current sensor
Lighted 7 times After the operation starts, a short or open
circuit is detected in the current sensor when
the compressor is not operating.
• Replace the outdoor power P.C. board.
—
Current sensor has been short or open cir-
cuited for 120 seconds.
○
Zero cross detecting circuit
5 times
Not
lighted
Zero cross signal cannot be detected while the
compressor is operating.
• Check the connecting wire between
outdoor control P.C. board and outdoor
power P.C. board.
—
The protection cut-out of the zero cross detect-
ing circuit operates 3 consecutive times.
○
Bus-bar voltage
6 times
Not
lighted
The bus-bar voltage exceeds
400 V or falls to 300 V or below during com-
pressor operating.
• Check the voltage of power supply.
• Replace the outdoor power P.C. board .
—
12-time
fl
ash
Compressor (open phase)
10
times
Not
lighted
Waveform of compressor current is distorted.
• Check the connection of the compres-
sor connecting wire.
• Refer to 11-6. " How to check in-
verter/compressor.
—
14-time
fl
ash
Power module
7 times
Not
lighted
The overcurrent is detected when the frequen-
cy of the compressor is 1 Hz or less.
• Refer to 11-6. " How to check in-
verter/compressor.
—
15-time
fl
ash
LEV and drain pump
Lighted Lighted The indoor unit detects an abnormality in the
LEV and drain pump.
• Refer to 11-6. "Check of LEV".
• Check the drain pump of the indoor
unit.
—
Operation start
Check the outdoor unit
LED indicator.
Refer to 11-6.
"Check of power supply".
• Indoor unit
serial signal
error
Refer to 11-6.
"How to
check
mis-wiring and
serial signal
error".
• COOL or
HEAT
operation only
Refer to 11-6.
"Check of
R.V. coil".
• When cooling,
room is not
cool.
Refer to 11-6.
"How to check
inverter/
compressor".
• When cooling, heat
exchanger of
non-operating indoor
unit frosts.
•When heating, non-
operating indoor unit
gets warm.
Refer to 11-6.
"Check of LEV".
• When heating,
room does not get
warm.
Refer to 11-6.
"How to check
inverter/compressor".
Check mis-piping,
shortage of capacity.
• When cooling
dew drops in the
non-operating
indoor unit.
Check of
miss-piping.
Refer to 11-4.
"Troubleshooting check table".
Both LED1 and
LED2 are OFF.
Both LED 1 and
LED 2 are lighting.
LED 1 or LED 2
has blinked.
11-3. INSTRUCTION OF TROUBLESHOOTING
• Check the indoor unit with referring to the indoor unit service manual, and confirm that there is any problem in the indoor
unit.
Then, check the outdoor unit with referring to this page.
NOTE
: Blinking patterns of this mode differ from the ones of Troubleshooting check table (11-4.).
OBH560G
