Mitsubishi Electric MXZ-3E54VA-E1 Service Manual page 90

11-4. TROUBLESHOOTING CHECK TABLE
Indication
No. Symptom
LED1(Red) LED2(Yellow)
1 Outdoor
Lighted
unit does
not operate.
2
Lighted
3
Lighted
4
Lighted
5
Lighted
6
Lighted
7
Lighted
8
Lighted
9
Lighted
10
Lighted
11
Lighted
12
Lighted
13 Lighted
14 'Outdoor unit
stops and
restarts
Twice Not lighted
3 minutes
later' is
repeated.
15
3 times Not lighted
16
4 times Not lighted
17
5 times Not lighted
18
6 times Not lighted
19
8 times Not lighted
20
9 times Not lighted
21
11 times Not lighted
OBH723D
Abnormal point / Con-
dition
Once LEV and drain pump
Outdoor power
Twice
system
Discharge temperature
3 times
thermistor
Fin temperature
thermistor
4 times
P. C. board tempera-
ture thermistor
Ambient temperature
thermistor
Outdoor heat ex-
changer temperature
5 times
thermistor
Defrost thermistor
Zero cross detecting
6 times circuit (Outdoor control
P.C. board)
7 times Outdoor control system
8 times Current sensor
Communication error
between P.C. boards
11 times
M-NET communication
error
Zero cross detecting
12 times circuit (Outdoor power
P.C. board)
13 times Current sensor
14 times Voltage sensor
15 times Relay operation
IPM protection
Lock protection
Discharge temperature
protection
Fin temperature
protection
P.C. board temperature
protection
High pressure
protection
Pre-heating protection
Converter protection
Bus-bar voltage
protection
Low outside tempera-
ture protection(cooling)
Condition
The indoor unit detects an abnormality in the LEV
and drain pump.
Overcurrent protection cut-out operates 3 consecu-
tive times within 1 minute after the compressor
gets started, or converter protection cut-out or bus-
bar voltage protection cut-out operates 3 consecu-
tive times within 3 minutes after startup.
A short circuit is detected in the thermistor during
operation, or an open circuit is detected in the ther-
mistor after 10 minutes of compressor startup.
A short or open circuit is detected in the thermistor
during operation.
A short or open circuit is detected in the thermistor
during operation.
A short circuit is detected in the thermistor during
operation, or an open circuit is detected in the ther-
mistor after 5 minutes (in cooling) and 10 minutes
(in heating) of compressor startup.
A short circuit is detected in the thermistor during
operation, or an open circuit is detected in the ther-
mistor after 5 minutes of compressor startup.
Zero cross signal cannot be detected.
The nonvolatile memory data cannot be read
properly.
Current sensor protection cut-out operates 2 con-
secutive times.
The communication protection cut-out between
boards operates 2 consecutive times.
M-NET adapter P.C. board detects an abnormality
in the communication error.
The protection cut-out of the zero cross detecting
circuit operates 10 consecutive times.
A short or open circuit is detected in the input cur-
rent detection circuit during operation.
A short or open circuit is detected in the input volt-
age detection circuit during operation.
No relay operation is detected during operation.
Overcurrent is detected after 30 seconds of com-
pressor startup.
Overcurrent is detected within 30 seconds of com-
pressor startup.
The discharge temperature exceeds 115°C (MXZ-
3E54/3E68/4E72VA)/ 106°C(MXZ-4E83/5E102VA,
MXZ-2E52VAHZ)/ 116°C (MXZ-4E83VAHZ) during
operation.
Compressor can restart if discharge temperature
thermistor reads 80°C (MXZ-3E54/3E68/4E72VA)/
95°C (MXZ-4E83/5E102VA, MXZ-2E52VAHZ)/
100°C (MXZ-4E83VAHZ) or less 3 minutes later.
The f n temperature exceeds during operation.
The P.C. board temperature exceeds during opera-
tion.
High pressure is detected with the high pressure
switch (HPS) during operation.
The outdoor heat exchanger temperature exceeds
70°C during cooling or the indoor gas pipe tem-
perature exceeds 70°C during heating.
Overcurrent is detected during pre-heating.
A failure is detected in the operation of the convert-
er during operation.
The bus-bar voltage exceeds 400 V or falls to low
level during compressor operating.
The ambient became -12°C or less.
90
Remedy
• Refer to 11-6. "Check of LEV".
• Check the drain pump of the indoor unit.
• Check the connection of the compressor connect-
ing wire.
• Refer to 11-6. "How to check inverter/compres-
sor".
• Check the stop valve.
• Refer to 11-6. "Check of outdoor thermistors".
• Refer to 11-6. "Check of outdoor thermistors".
• Replace the outdoor control P.C. board.
• Refer to 11-6. "Check of outdoor thermistors".
• Replace the outdoor control P.C. board.
• Replace the outdoor control P.C. board.
• Replace the outdoor power P.C. board.
• Check the connecting wire between outdoor con-
trol P.C. board and outdoor power P.C. board.
• Check the connecting wire between M-NET
adapter P.C. board and outdoor control P.C.
board, or terminal block.
• Replace the outdoor power P.C. board.
• Replace the outdoor power P.C. board.
• Replace the outdoor power P.C. board.
• Replace the outdoor power P.C. board.
• Reconnect compressor connector.
• Refer to 11-6. "How to check inverter/
compressor".
• Check the stop valve.
• Check the power module (PAM module).
• Check the amount of gas and refrigerant circuit.
• Refer to 11-6. "Check of LEV".
•Check refrigerant circuit and refrigerant amount.
•Refer to 11-6. "Check of outdoor fan motor".
• Check around of gas and the refrigerant circuit.
• Check the stop valve.
• Reconnect compressor connector.
• Refer to 11-6. "How to check inverter/
compressor".
• Check the power module.
• Replace the outdoor power P.C. board.
• Check the voltage of power supply.
• Replace the outdoor power P.C. board or the out-
door control P.C. board.
• Refer to 11-6. "Check of bus-bar voltage".
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