37
ON
OFF
2.5-second OFF
2.5-second OFF
NOTE 1. The location of LED is illustrated at the right figure. Refer to 11-7.1.
2. LED is lighted during normal operation.
The flashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the flashing frequency is “2”.
Abnormal point/ Condition
When it consecutively occurs 3 times that the compressor stops
for overcurrent protection within 1minute after start-up.
When discharge temperature thermistor, fin temperature
thermistor, defrost thermistor, P.C. board temperature
thermistor or ambient temperature thermistor shorts or opens
during compressor running.
When nonvolatile memory data cannot be read properly.
(When POWER lamp of the indoor unit lights up or flashes 7-time.)
When 14A(MUZ-GA25VA,MUZ-GA25VAH)/ 24A(MUZ-GA35VA,
MUZ-GA35VAH) current flows into intelligent power module.
When temperature of discharge temperature thermistor
exceeds 116
:
, compressor stops. Compressor can restart if
discharge temperature thermistor reads 100
:
or less 3
minutes later.
When temperature of fin temperature thermistor on the heat
sink exceeds 82
:
(MUZ-GA25VA,MUZ-GA25VAH)/ 83
:
(MUZ-GA35VA,MUZ-GA35VAH) or temperature of P.C. board
temperature thermistor on the inverter P.C.board exceeds
81
:
(MUZ-GA25VA,MUZ-GA25VAH)/ 85
:
(MUZ-GA35VA,
MUZ-GA35VAH).
When indoor coil thermistor exceeds 70
:
in HEAT mode.
When the defrost thermistor exceeds 70
:
in COOL mode.
When current from power outlet exceeds 5.2A(MUZ-GA25VA,
MUZ-GA25VAH)/ 6.1A(MUZ-GA35VA,MUZ-GA35VAH),
compressor frequency lowers.
When temperature of indoor coil thermistor exceeds 55
:
in
HEAT mode, compressor frequency lowers.
When indoor coil thermistor reads 8
:
or less in COOL mode,
compressor frequency lowers.
When temperature of discharge temperature thermistor
exceeds 111
:
,
compressor frequency lowers.
When temperature of discharge temperature thermistor has
been 50
:
or less for 20 minutes.
No.
1
2
3
6
7
8
9
14
15
16
17
18
Symptom
LED indication
Condition
Correspondence
Outdoor unit
does not
operate
'Outdoor unit
stops and
restarts 3
minutes later'
is repeated
Outdoor unit
operates
Outdoor unit
operates
1-time flash every
2.5 seconds
2-time flash
2.5 seconds OFF
3-time flash
2.5 seconds OFF
4-time flash
2.5 seconds OFF
5-time flash
2.5 seconds OFF
1-time flash
2.5 seconds OFF
3-time flash
2.5 seconds OFF
4-time flash
2.5 seconds OFF
7-time flash
2.5 seconds OFF
Outdoor power
system
Outdoor
thermistors
Outdoor control
system
Overcurrent
protection
Discharge
temperature
overheat
protection
Fin temperature
/P.C. board
temperature
thermistor
overheat protection
High pressure
protection
Frequency drop by
current protection
Frequency drop by
high pressure
protection
Frequency drop by
defrosting in COOL
mode
Frequency drop by
discharge
temperature
protection
Low discharge
temperature
protection
· Check stop valve.
· Reconnect connector of compressor.
· Refer to 11-6.
A
"How to check
inverter/ compressor".
· Refer to 11-6.
G
"Check of outdoor
thermistors".
· Check stop valve.
· Reconnect connector of compressor.
· Refer to 11-6.
A
"How to check
inverter/compressor".
Replace inverter P.C. board.
· Check refrigerant circuit and
refrigerant amount.
· Refer to 11-6.
L
"Check of LEV".
· Check around outdoor unit.
· Check outdoor unit air passage.
· Refer to 11-6.
I
"Check of outdoor
fan motor".
· Check refrigerant circuit and
refrigerant amount.
· Check stop valve.
The unit is normal, but check the
following.
· Check if indoor filters are clogged.
· Check if refrigerant is short.
· Check if indoor/outdoor unit air
circulation is short cycled.
· Refer to 11-6.
L
"Check of LEV".
· Check refrigerant circuit and
refrigerant amount.
Inverter P.C. board (Parts side)
LED
Flashing
Refer to 11-6.
O
"How to check mis-
wiring and serial signal error.
When the communication fails between the indoor and outdoor
unit for 3 minutes.
Serial signal
8-time flash
2.5 seconds OFF
Compressor
synchronous
abnormality
When the waveform of compressor current is distorted.
· Reconnect connector of compressor.
· Refer to 11-6.
A
"How to check
inverter/compressor".
8-time flash
2.5 seconds OFF
PAM protection
PAM:
Pulse
Amplitude
Modulation
When the overcurrent flows into IGBT(Insulated Gate Bipolar
transistor : TR821) or when the bus-bar voltage reaches 320V
or more, PAM stops and restarts.
This is not malfunction.
PAM protection will be activated in
the following cases;
1
Instantaneous power voltage drop
(Short time power failure)
2
When the power supply voltage is
high.
9-time flash
2.5 seconds OFF
Inverter check
mode
When the connector of compressor is disconnected, inverter
check mode starts.
Check if the connector of the
compressor is correctly connected.
Refer to 11-6.
A
"How to check
inverter/ compressor".
4
10
19
10-time flash
2.5 seconds OFF
Outdoor fan motor
6-time flash
2.5 seconds OFF
When outdoor fan has stopped 3 times in a row within 30
seconds after outdoor fan start-up.
· Refer to 11-6.
I
"Check of outdoor
fan motor.
· Refer to 11-6.
N
"Check of inverter
P.C. board.
11
12
13
12-time flash
2.5 seconds OFF
Each phase
current of
compressor
When each phase current of compressor cannot be detected
normally
· Refer to 11-6.
A
"How to check
inverter/compressor".
13-time flash
2.5 seconds OFF
DC voltage
When DC voltage of inverter cannot be detected normally.
· Refer to 11-6.
A
"How to check
inverter/compressor".
· Check refrigerant circuit and
refrigerant amount.
· Refer to 11-6.
L
"Check of LEV".
· Refer to 11-6.
G
"Check of
outdoor thermistors".
Refer to 11-2.2. Flow chart of the
detailed outdoor unit failure mode
recall function.
When outdoor unit is defective.
Outdoor unit
(Other abnormality)
5
14-time flash
2.5 seconds OFF
0.5-second ON
0.5-second ON
11-4. Troubleshooting check table
OB379C--2qxp 07.2.1 2:28 PM Page 37
