26
No.
Symptom
LED indication
Abnormal point/
Condition
Condition
Remedy
16
Outdoor unit
operates.
1-time blink
2.5 seconds OFF
Frequency drop by
current protection
Current from power outlet is nearing breaker capacity.
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.
17
3-time blink
2.5 seconds OFF
Frequency drop by
high pressure pro-
tection
Temperature of indoor coil thermistor exceeds 131 °F (55°C)
in HEAT mode, compressor frequency lowers.
Frequency drop by
defrosting in COOL
mode
Indoor coil thermistor reads 46°F (8°C) or less in COOL mode,
compressor frequency lowers.
18
4-time blink
2.5 seconds OFF
Frequency drop by
discharge tempera-
ture protection
Temperature of discharge temperature thermistor exceeds
232°F (111°C), compressor frequency lowers.
• Check refrigerant circuit and refrig-
erant amount.
• Refer to 10-5. "Check of LEV".
• Refer to 10-5. "Check of outdoor
thermistors".
19
Outdoor unit
operates.
7-time blink
2.5 seconds OFF
Low discharge tem-
perature protection
Temperature of discharge temperature thermistor has been
122°F (50°C) or less for 20 minutes.
• Refer to 10-5. "Check of LEV".
• Check refrigerant circuit and refrig-
erant amount.
20
8-time blink
2.5 seconds OFF
Zero cross detecting
circuit
Zero cross signal cannot be detected.
• It occurs with following cases.
1 Instantaneous power voltage
drop. (Short time power failure)
2 Distortion of primary voltage
• Refer to 10-5. "Check of power
supply".
21
9-time blink
2.5 seconds OFF
Inverter check mode The connector of compressor is disconnected, inverter check
mode starts.
• Check if the connector of the com-
pressor is correctly connected.
Refer to 10-5. "How to check
inverter/compressor".
NOTE:
1. The location of LED is illustrated at the right figure. Refer to 10-6.1.
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
OFF
2.5-second OFF
2.5-second OFF
0.5-second ON
0.5-second ON
Inverter P.C. board
MUZ-GS30/36NA
MUZ-GS30/36NAH
MUY-GS30/36NA
LED
→
Blinking
OBH875A
