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No.
Symptom
LED indication
MUZ-LN25/35
Outdoor unit
operates.
5-time blink
20
2.5 seconds OFF
7-time blink
2.5 seconds OFF
21
8-time blink
2.5 seconds OFF
22
9-time blink
2.5 seconds OFF
23
NOTE: 1. The location of LED is illustrated at the right figure. Refer to 12-6.1.
2. LED is lit during normal operation.
The blinking frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the blinking frequency is "2".
ON
2.5-second OFF
OFF
OBH767G
Abnormal point/ Con-
dition
Outside temperature
When the outside temperature thermistor shorts or opens,
thermistor protec-
protective operation without that thermistor is performed.
tion
Low discharge tem-
Temperature of discharge temperature thermistor has been
perature protection
50°C or less for 20 minutes.
MUZ-LN25/35/50
The overcurrent flows into PFC (Power factor correction:
IC820) or the bus-bar voltage reaches 394 V or more, PAM
PAM protection
stops and restarts.
PAM: Pulse Ampli-
tude Modulation
MUZ-LN60
Zero cross signal cannot be detected.
Zero cross detecting
circuit
Inverter check mode The connector of compressor is disconnected, inverter check
mode starts.
0.5-second ON
2.5-second OFF
Condition
0.5-second ON
57
Remedy
• Refer to 12-5.
Check of outdoor
thermistors.
• Refer to 12-5.
"Check of LEV".
• Check refrigerant circuit and refrig-
erant amount.
This is not malfunction. PAM pro-
tection will be activated in the fol-
lowing cases:
1 Instantaneous power voltage
drop. (Short time power failure)
2 When the power supply voltage
is high.
• It occurs with following cases.
1 Instantaneous power voltage
drop. (Short time power failure)
2 Distortion of primary voltage
• Refer to 12-5.
"Check of power
supply".
• Check if the connector of the com-
pressor is correctly connected.
Refer to 12-5.
"How to check
inverter/compressor".
Inverter P.C. board
MUZ-LN25/35/50VG
MUZ-LN25/35/50VG2
LED
Blinking →
MUZ-LN60VG
Blinking
→
LED
MUZ-LN60VG2
LED
Blinking →
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