Mitsubishi MUY-A15NA, Service Manual

Page: 39 / 79

39
Primary current protection
Secondary current protection
High-pressure protection
(MUZ)
Defrosting in cooling
(MUZ)
3 times
Lighting
Discharge temperature
protection
• Check refrigerant circuit and refrigerant amount.
• Refer to 10-5. L "Check of LEV".
• Refer to 10-5. G "Check of outdoor thermistors".
4 times Lighting
Low discharge
temperature protection
• Refer to 10-5.
L
"Check of LEV".
• Check refrigerant circuit and refrigerant amount.
5 times Lighting
Cooling high-pressure
protection
This symptom does not mean any abnormality of the
product, but check the following points.
•
Check if indoor filters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air circulation is short cycled.
-
-
These symptoms do not mean any abnormality of the
product, but check the following points.
•
Check if indoor filters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air circulation is short cycled.
Twice Lighting
Once Lighting
When the discharge temperature exceeds 212
°
F (100 : ) during operation.
When the frequency of the compressor is kept 80Hz or more and
the discharge temperature is kept under
102
°
F (39
:
) for more than 20
minutes.
When the outdoor heat exchanger temperature exceeds 136
°
F (58
:
)
during operation.
9 times Lighting
Inverter check mode
Lighting
Lighting Normal
When the unit is operated with emergency operation switch.
-
When the input current exceeds 15A.
When the current of the compressor exceeds 15A.
When the indoor gas pipe temperature exceeds 113
°
F (45 : ) during heating.
When the indoor gas pipe temperature falls 37
°
F (3 : ) or below during
cooling.
LED1(Red) LED2(Yellow)
Abnormal point / Condition Correspondence
Indication
Condition
Outdoor unit
operates.
Outdoor unit
operates
No. Symptom
20
21
22
23
24
25
26
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