Mitsubishi MXZ-2A20NA, Service Manual

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58
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 11-6.
D
"Check of LEV".
• Refer to 11-6.
F
"Check of outdoor thermistors".
4 times
Lighting
Low discharge
temperature protection
• Refer to 11-6.
D
"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)
LED2 LED1
Lighting
LED1 LED2
Lighting
MXZ-2A20NA, MXZ-2A20NA-
1
, 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
ON
OFF
2.5-second OFF
2.5-second OFF
The flashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the flashing frequency is “2”.
0.5-second ON
0.5-second ON
NOTE 1. The location of LED is illustrated at the right figure. Refer to 11-7.1.
2. LED is lighted during normal operation.
OB444C--2.qxp 07.10.18 2:32 PM Page 58