Mitsubishi Electric Mr. SLIM MSZ-FA25VA Technical Manual página 279

11-3. Troubleshooting check table
Symptom
No. LED indication
1-time flash every
Outdoor unit
2.5 seconds
1 does not
operate.
2
3
6-time flash
4
2.5 seconds OFF
11-time flash
5 2.5 seconds OFF
14-time flash
6 2.5 seconds OFF
2-time flash
'Outdoor unit
2.5 seconds OFF
stops and
7
restarts 3
minutes later'
is repeated.
3-time flash
2.5 seconds OFF
8
4-time flash
2.5 seconds OFF
9
5-time flash
2.5 seconds OFF
10
8-time flash
2.5 seconds OFF
11
12-time flash
12
2.5 seconds OFF
13-time flash
2.5 seconds OFF
13
1-time flash
Outdoor unit
2.5 seconds OFF
14 operates.
3-time flash
2.5 seconds OFF
15
4-time flash
2.5 seconds OFF
16
Outdoor unit
7-time flash
operates.
17
2.5 seconds OFF
8-time flash
2.5 seconds OFF
18
9-time flash
2.5 seconds OFF
19
NOTE: 1. The location of LED is illustrated at the right figure. Refer to 11-6.1.
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".
ON
2.5-second OFF
OFF
Abnormal point/ Condition
Over current protection stop is continuously performed three
Outdoor power
system
times within 1 minute after the compressor gets started, or
failure of restart of compressor has repeated 24 times.
Discharge temperature thermistor, fin temperature thermistor,
Outdoor
defrost thermistor, P.C. board temperature thermistor shorts or
thermistors
opens during compressor running.
Nonvolatile memory data cannot be read properly.
Outdoor control
system
(The left lamp of OPERATION INDICATOR lamp of the
indoor unit lights up or flashes 7-time.)
The communication fails between the indoor and outdoor unit
Serial signal
for 3 minutes.
Stop valve/
Closed valve is detected by compressor current.
Closed valve
Outdoor unit Outdoor unit is defective.
(Other abnormality)
Overcurrent 12A(MUZ-HC25)/ 14A(MUZ-HC35) current flows into intelligent
protection power module, or compressor repeats after 15 seconds when
overcurrent protection occures with in 10 seconds after
compressor starts. (Repeated 24 times at Maximum)
Discharge
Temperature of discharge temperature thermistor exceeds
temperature
116: , compressor stops. Compressor can restart if discharge
overheat
temperature thermistor reads 100:
protection
Fin temperature
Temperature of fin temperature thermistor on the heat sink
/P.C. board
exceeds 82: (MUZ-HC25)/ 83
temperature of P.C. board temperature thermistor on the inverter P.C.board
°C
thermistor exceeds 81 (MUZ-HC25)/ 85: (MUZ-HC35).
overheat protection
Indoor coil thermistor exceeds 70
High pressure
When the defrost thermistor exceeds 70:
protection
Compressor
The waveform of compressor current is distorted.
synchronous
abnormality
Each phase
Each phase current of compressor cannot be detected
current of
normally
compressor
DC voltage DC voltage of inverter cannot be detected normally.
Frequency drop by
Current from power outlet exceeds 5.2A(MUZ-HC25)/
current protection
6.1A(MUZ-HC35), compressor frequency lowers.
Frequency drop by
Temperature of indoor coil thermistor exceeds 55
high pressure
mode, compressor frequency lowers.
protection
Frequency drop by Indoor coil thermistor reads 8
defrosting in COOL compressor frequency lowers.
mode
Frequency drop by Temperature of discharge temperature thermistor exceeds
°C
discharge 111 ,
temperature compressor frequency lowers.
protection
Low discharge
Temperature of discharge temperature thermistor has been
temperature
°C
50 or less for 20 minutes.
protection
The overcurrent flows into IGBT(Insulated Gate Bipolar
PAM protection
transistor : TR821) or when the bus-bar voltage reaches 320V
or more, PAM stops and restarts.
PAM:
Pulse
Amplitude
Modulation
The connector of compressor is disconnected, inverter check
Inverter check
mode starts.
mode
0.5-second ON
2.5-second OFF
Resolución de averías
Condition
or less 3 minutes later.
°C
(MUZ-HC35) or temperature
°C
in HEAT mode.
in COOL mode.
°C
in HEAT
°C
or less in COOL mode,
0.5-second ON
Correspondence
· Reconnect connector of compressor.
· Refer to 11-5.A "How to check
inverter/ compressor".
· Check stop valve.
· Refer to 11-5.G "Check of outdoor
thermistors".
· Replace inverter P.C. board.
Refer to 11-5.K "How to check mis-
wiring and serial signal error.
· Check stop valve.
·Refer to 11-2.2. "Flow chart of the
detailed outdoor unit failure mode
recall function".
· Reconnect connector of compressor.
· Refer to 11-5.A "How to check
inverter/compressor".
· Check stop valve.
· Check refrigerant circuit and
refrigerant amount.
· Check around outdoor unit.
· Check outdoor unit air passage.
· Refer to 11-5.I "Check of outdoor
fan motor".
· Check refrigerant circuit and
refrigerant amount.
· Check stop valve.
· Reconnect connector of compressor.
· Refer to 11-5.A "How to check
inverter/compressor".
· Refer to 11-5.A "How to check
inverter/compressor".
· Refer to 11-5.A "How to check
inverter/compressor".
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.
· Check refrigerant circuit and
refrigerant amount.
· Refer to 11-5.G "Check of
outdoor thermistors".
· Check refrigerant circuit and
refrigerant amount.
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.
Check if the connector of the
compressor is correctly connected.
Refer to 11-5.A "How to check
inverter/ compressor".
Inverter P.C. board (Parts side)
LED
Flashing
279