Mitsubishi Electric Mr.Slim MUZ-GC25NA - C1, Service Manual

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32
No. Symptom
Indication
Abnormal point /
Condition
Condition Correspondence
LED1 (Red)
LED2
(Yellow)
20
Outdoor unit
operates.
Once Lighting
Primary current protection The input current exceeds 15 A.
These symptoms do not mean any ab-
normality of the product, but check the
following points.
• Check if indoor fi lters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air circu-
lation is short cycled.
Secondary current protec-
tion
The current of the compressor exceeds 15 A.
21
Twice Lighting
High-pressure protection The indoor gas pipe temperature exceeds 45°C during heating.
Defrosting in cooling The indoor gas pipe temperature falls 3°C or below during cooling.
22
3 times Lighting
Discharge temperature
protection
The discharge temperature exceeds 100°C during operation.
• Check refrigerant circuit and refriger-
ant amount.
• Refer to 9-5
. "Check of LEV".
• Refer to 9-5
. "Check of outdoor
thermistors".
23
4 times Lighting Low discharge tempera-
ture protection
The frequency of the compressor is kept 80 Hz or more and the dis-
charge temperature is kept under 39°C for more than 20 minutes.
• Refer to 9-5
. "Check of LEV".
• Check refrigerant circuit and refriger-
ant amount.
24
5 times Lighting
Cooling high-pressure
protection
The outdoor heat exchanger temperature exceeds 58°C during op-
eration.
This symptom does not mean any ab-
normality of the product, but check the
following points.
• Check if indoor fi lters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air circu-
lation is short cycled.
25
Outdoor unit
operates
9 times Lighting
Inverter check mode The unit is operated with emergency operation switch. -
26
Lighting Lighting
Normal - -