Mitsubishi Electric MUZ-FH09NA, Руководство по обслуживанию, Страница: 28 / 52

28
10-3. TROUBLESHOOTING CHECK TABLE
No. Symptom LED indication
Abnormal point/
Condition
Condition Remedy
1
Outdoor unit
does not op-
erate. 1-time fl ash every
2.5 seconds Outdoor power sys-
tem Overcurrent protection cut-out operates 3 consecutive times
within 1 minute after the compressor gets started.
• Reconnect connector of compres-
sor.
• Refer to 10-5. "How to check
inverter/compressor".
• Check stop valve.
2
Outdoor thermistors Discharge temperature thermistor, fi n temperature thermistor,
defrost thermistor, P.C. board temperature thermistor, outdoor
heat exchanger temperature thermistor or ambient tempera-
ture thermistor shorts or opens during compressor running.
• Refer to 10-5. "Check of outdoor
thermistors".
3
Outdoor control sys-
tem Nonvolatile memory data cannot be read properly.
(The left lamp of the OPERATION INDICATOR lamp on the
indoor unit lights up or fl ashes 7-time.)
• Replace inverter P.C. board.
4
6-time fl ash
2.5 seconds OFF Serial signal The communication fails between the indoor and outdoor unit
for 3 minutes.
• Check connection between the in-
verter P.C. board and the relay P.C.
board. (
FH15 )
• Refer to 10-5. "How to check
miswiring and serial signal error.
5
11-time fl ash
2.5 seconds OFF Stop valve/
Closed valve Closed valve is detected by compressor current.
• Check stop valve.
6
14-time fl ash
2.5 seconds OFF Outdoor unit
(Other abnormality) Outdoor unit is defective.
• Refer to 10-2.2. "Flow chart of the
detailed outdoor unit failure mode
recall function".
7
16-time fl ash
2.5 seconds OFF 4-way valve/
Pipe temperature
The 4-way valve does not work properly.
The indoor coil thermistor detects an abnormal temperature.
• Refer to 10-5. "Check of R.V.
coil".
• Replace the inverter P.C. board.
8
17-time fl ash
2.5 seconds OFF Outdoor refrigerant
system abnormality A closed valve and air trapped in the refrigerant circuit are
detected based on the temperature sensed by the indoor and
outdoor thermistors and the current of the compressor.
• Check for a gas leak in a
connecting piping etc.
• Check the stop valve.
• Refer to 10-5. “Check of outdoor
refrigerant circuit”.
9
'Outdoor unit
stops and
restarts 3
minutes later'
is repeated. 2-time fl ash
2.5 seconds OFF Overcurrent protec-
tion Large current fl ows into the power module (IC700) ( FH09/12 )/
IGBT module (IC700) ( FH15 ).
• Reconnect connector of compressor.
• Refer to 10-5. "How to check
inverter/compressor".
• Check stop valve.
10
3-time fl ash
2.5 seconds OFF Discharge tem-
perature overheat
protection Temperature of discharge temperature thermistor exceeds
241°F (116°C), compressor stops. Compressor can restart if
discharge temperature thermistor reads 212°F (100°C) or less
3 minutes later.
• Check refrigerant circuit and refrig-
erant amount.
• Refer to 10-5. "Check of LEV".
11
4-time fl ash
2.5 seconds OFF Fin temperature
/P.C. board tem-
perature thermistor
overheat protection Temperature of the fi n temperature thermistor on the heat sink
exceeds 167 ~ 187°F (75 ~ 86°C) (
FH09/12 )/167 ~ 176°F
(75 ~ 80°C) ( FH15 ) or temperature of P.C. board temperature
thermistor on the inverter P.C.board exceeds 162 ~ 185°F (72
~ 85°C) (
FH09/12 )/158 ~ 167°F (70 ~ 75°C) ( FH15 ).
• Check around outdoor unit.
• Check outdoor unit air passage.
• Refer to 10-5. "Check of outdoor
fan motor".
12
5-time fl ash
2.5 seconds OFF High pressure pro-
tection Indoor coil thermistor exceeds 158°F (70°C) in HEAT mode.
Defrost thermistor exceeds 158°F (70°C) in COOL mode.
• Check refrigerant circuit and refrig-
erant amount.
• Check stop valve.
13
8-time fl ash
2.5 seconds OFF Compressor syn-
chronous abnormal-
ity The waveform of compressor current is distorted.
• Reconnect connector of compressor.
• Refer to 10-5. "How to check
inverter/compressor".
14
10-time fl ash
2.5 seconds OFF Outdoor fan motor Outdoor fan has stopped 3 times in a row within 30 seconds
after outdoor fan start-up.
• Refer to 10-5. "Check of outdoor
fan motor.
• Refer to 10-5. "Check of inverter
P.C. board.
15
12-time fl ash
2.5 seconds OFF Each phase current
of compressor
Each phase current of compressor cannot be detected nor-
mally.
• Refer to 10-5. "How to check
inverter/compressor".
16
13-time fl ash
2.5 seconds OFF DC voltage DC voltage of inverter cannot be detected normally.
• It occurs with following case.
Instantaneous power voltage drop.
(Short time power failure) (
FH15 )
• Refer to 10-5. "Check of power
supply". ( FH15 )
• Refer to 10-5. "How to check in-
verter/compressor".
NOTE: 1. The location of LED is illustrated at the right fi gure. Refer to 10-6.1.
2. LED is lighted during normal operation.
The fl ashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the fl ashing frequency is “2”.
ON
OFF
2.5-second OFF
2.5-second OFF
0.5-second ON
0.5-second ON
LED
Flashing
→
MUZ-FH09/12NA(H)
Inverter P.C. board
MUZ-FH15NA(H)
LED
→
Flashing
OBH584A