Mitsubishi Electric MXZ-2A20NA - 1, Service Manual

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Primary current protection
Secondary current protection
High-pressure protection
Defrosting in cooling
3 times
Lighting
Discharge temperature
protection
• Check refrigerant circuit and refrigerant amount.
• Refer to 12-6. "Check of LEV".
• Refer to 12-6. "Check of outdoor thermistors".
4 times Lighting
Low discharge
temperature protection
• Refer to 12-6. "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 frequency of the compressor is kept 80Hz or more and
the discharge temperature is kept under 122°F(COOL mode)
/104°F(HEAT mode) for more than 40 minutes.
When the frequency of the compressor is kept 80Hz or more and
the discharge temperature is kept under 102.2°F for more than 20
minutes.
When the outdoor heat exchanger temperature exceeds 136.4°F
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 during heating.
When the indoor gas pipe temperature falls 37.4°F or below during cooling.
Outdoor electronic control P.C. board(Parts side)
LED2LED1
Lighting
LED1LED2
Lighting
MXZ-2A20NA, MXZ-2A20NA-
1
, MXZ-2A20NA-
2
MXZ-3A30NA
MXZ-3A30NA-
1
, MXZ-4A36NA
LED1(Red) LED2(Yellow)
Abnormal point / Condition Correspondence
Indication
Condition
Outdoor unit
operates.
Outdoor unit
operates
normally.
No. Symptom
21
22
23
24
25
26
27
The flashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the flashing frequency is “2”.
ON
OFF
2.5-second OFF
2.5-second OFF
0.5-second ON
0.5-second ON
NOTE 1. The location of LED is illustrated at the right figure. Refer to 12-7.1.
2. LED is lighted during normal operation.