Mitsubishi Electric Mr.Slim MUZ-GC25NA - C1, Руководство по обслуживанию

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9-3. TROUBLESHOOTING CHECK TABLE
MUZ-GC25/35NA
No. Symptom LED indication
Abnormal point/
Condition
Condition Correspondence
1
Outdoor unit
does not
operate.
1-time fl ash every
2.5 seconds
Outdoor power system Overcurrent protection stop is continuously performed 3 times
within 1 minute after the compressor gets started.
• Reconnect connector of
compressor.
• Refer to 9-5. "How to check
inverter/compressor".
• Check stop valve.
2
Outdoor thermistors Discharge temperature thermistor, fi n temperature thermistor,
defrost thermistor or P.C. board temperature thermistor shorts
or opens during compressor running.
• Refer to 9-5. "Check of outdoor
thermistors".
3
Outdoor control system Nonvolatile memory data cannot be read properly. (When the
upper lamp of OPERATION INDICATOR lamp of 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.
Refer to 9-5. "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 9-2.2. "Flow chart of the
detailed outdoor unit failure mode
recall function".
7
'Outdoor unit
stops and
restarts 3
minutes later'
is repeated.
2-time fl ash
2.5 seconds OFF
Overcurrent protection Large current fl ows into intelligent power module. • Reconnect connector of
compressor.
• Refer to 9-5. "How to check
inverter/compressor".
• Check stop valve.
8
3-time fl ash
2.5 seconds OFF
Discharge temperature
overheat protection
Temperature of discharge temperature thermistor exceeds 116
°C, compressor stops. Compressor can restart if discharge
temperature thermistor reads 100°C or less 3 minutes later.
• Check refrigerant circuit and
refrigerant amount.
• Refer to 9-5. "Check of LEV".
9
4-time fl ash
2.5 seconds OFF
Fin temperature /P.C.
board temperature
thermistor overheat
protection
Temperature of fi n temperature thermistor on the heat sink
exceeds 82 - 83°C or temperature of P.C. board temperature
thermistor on the inverter P.C.board exceeds 81 - 85°C.
• Check around outdoor unit.
• Check outdoor unit air passage.
• Refer to 9-5. "Check of outdoor
fan motor".
10
5-time fl ash
2.5 seconds OFF
High pressure
protection
Indoor coil thermistor exceeds 70°C in HEAT mode. Defrost
thermistor exceeds 70°C in COOL mode.
• Check refrigerant circuit and
refrigerant amount.
• Check stop valve.
11
8-time fl ash
2.5 seconds OFF
Compressor
synchronous
abnormality
The waveform of compressor current is distorted. • Reconnect connector of
compressor.
• Refer to 9-5. "How to check
inverter/compressor".
12
12-time fl ash
2.5 seconds OFF
Each phase current of
compressor
Each phase current of compressor cannot be detected normally • Refer to 9-5. "How to check
inverter/compressor".
13
13-time fl ash
2.5 seconds OFF
DC voltage DC voltage of inverter cannot be detected normally. • Refer to 9-5. "How to check
inverter/compressor".
14 Outdoor unit
operates.
1-time fl ash
2.5 seconds OFF
Frequency drop by
current protection
Current from power outlet reaches the protection current, and
compressor frequency lowers.
The unit is normal, but check the
following.
• Check if indoor fi lters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air
circulation is short cycled.
15
3-time fl ash
2.5 seconds OFF
Frequency drop by high
pressure protection
Temperature of indoor coil thermistor exceeds 55°C in HEAT
mode, compressor frequency lowers.
Frequency drop by
defrosting in COOL
mode
Indoor coil thermistor reads 8°C or less in COOL mode,
compressor frequency lowers.
16
4-time fl ash
2.5 seconds OFF
Frequency drop by
discharge temperature
protection
Temperature of discharge temperature thermistor exceeds 111°
C, compressor frequency lowers.
• Check refrigerant circuit and
refrigerant amount.
• Refer to 9-5. "Check of LEV".
• Refer to 9-5. "Check of outdoor
thermistors".
17
Outdoor unit
operates.
7-time fl ash
2.5 seconds OFF
Low discharge
temperature protection
Temperature of discharge temperature thermistor has been 50°
C or less for 20 minutes.
• Refer to 9-5. "Check of LEV".
• Check refrigerant circuit and
refrigerant amount.
18
8-time fl ash
2.5 seconds OFF
PAM protection PAM:
Pulse Amplitude
Modulation
The overcurrent fl ows into IGBT (Insulated Gate Bipolar
transistor : TR821) or when the bus-bar voltage reaches 320 V
or more, PAM stops and restarts.
This is not malfunction. PAM
protection will be activated in the
following cases;
Instantaneous power voltage
drop. (Short time power failure)
When the power supply voltage
is high.
19
9-time fl ash
2.5 seconds OFF
Inverter check mode The connector of compressor is disconnected, inverter check
mode starts.
Check if the connector of the
compressor is correctly connected.
Refer to 9-5. "How to check
inverter/compressor".
NOTE : 1. The location of LED is illustrated at the right fi gure. Refer to 9-6.1.
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".
Inverter P.C. board (Parts side)
LED
Flashing
ON
OFF
2.5-second OFF
2.5-second OFF
0.5-second ON
0.5-second ON