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65 

 

Condition of the  

air conditioner 

Cooling Mode 

Heating Mode 

Low Pressure 

High Pressure 

Electric current 

during operation

Low Pressure 

High Pressure 

Electric current 

during operation

Insufficient refrigerant 

(gas leakage) 

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Clogged capillary tube or 

Strainer 

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Short circuit in the indoor unit 

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Heat radiation deficiency 

of the outdoor unit 

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Inefficient compression 

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•  Carry out the measurement of pressure, electric current, and temperature fifteen minutes after an operation is started. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

66 

  Once abnormality has occurred during operation, the unit will stop its operation, and OFF/ON operation LED OFF. 

  OFF indicator does not shown on remote control display. 

  In operation after breakdown repair, the last error code abnormality will be stored in EEPROM. 

  To make a diagnosis 

1.  OFF/ON operation LED OFF and the unit automatically stops the operation, but the OFF indicator does not 

shown. 

2.  Press CHECK button continuously for 5 seconds. 
3.  “- -” will be displayed on the remote controller display. 
4. Press 

timer 

▲ or ▼ button on the remote control. The error code “H00” (no abnormality) will be displayed. 

5.  Every press of the button (▲ or ▼) will increase the error code number. 
6.  When the displayed error code matches the unit's error code, OFF/ON operation LED will be ON 

continuously. 

7.  The breakdown diagnosis mode will be cancelled by pressing CHECK button continuously for 5 seconds or 

wait for 30 seconds 

 
  AC Reset button 

When AC Reset button is pressed, the error code 
will be reset so that the unit will be able to operate 
and recheck if any error occurred. 

 

 

 

  To display memorized error status: 

1  Turn ON the power supply. 
2  Press CHECK button continuously for 5 seconds. 
3  “- -” will be displayed on the remote controller display. 
4 Press 

timer 

▲ or ▼ button on the remote control. The error code "H00" (no abnormality) will be displayed. 

5  Every press of the button (▲ or ▼) will increase the error code number. 
6  When the displayed error code matches the unit's error code, OFF/ON operation LED will be ON 

continuously. 

7  The breakdown diagnosis mode will be cancelled by pressing CHECK button continuously for 5 seconds or 

wait for 30 seconds. 

 
 
 
 
 
 
 
 
 

67 

 

H00 

No memory of failure 

— 

Normal operation

— 

— 

H11 

Indoor/outdoor 
abnormal 
communication 

After operation for 
1 minute 

Indoor fan only 
operation can 
start by entering 
into force cooling
operation 

Indoor/outdoor 
communication not 
establish 

 Indoor/outdoor wire terminal 

 Indoor/outdoor PCB 

 Indoor/outdoor connection wire 

H12 

Indoor unit capacity 
unmatched 

90s after power 
supply 

— 

Total indoor capability 
more than maximum limit 
or less than minimum limit, 
or number of indoor unit 
less than two 

 Indoor/outdoor connection wire 

 Indoor/outdoor PCB 

  Specification and combination 

table in catalogue 

H14 

Indoor intake air 
temperature sensor 
abnormality 

Continuous for 5s 

— 

Indoor intake air 
temperature sensor open 
or short circuit 

  Indoor intake air temperature 

sensor lead wire and connector 

H15 

Compressor 
temperature sensor 
abnormality 

Continuous for 5s 

— 

Compressor temperature 
sensor open or short circuit 

 Compressor temperature 

sensor lead wire and connector 

H16 

Outdoor current 
transformer (CT) 
abnormality 

— — 

Current transformer faulty 
or compressor faulty 

  Outdoor PCB faulty or 

compressor faulty 

H19 

Indoor fan motor 
mechanism lock 

Continuous 
happen for 7 times 

— 

Indoor fan motor lock or 
feedback abnormal 

  Fan motor lead wire and 

connector 

  Fan motor lock or block 

H21 

Indoor float switch 
operation abnormal 

— — 

— 

— 

H23 

Indoor heat 
exchanger 
temperature sensor 
abnormality 

Continuous for 5s 

— 

Indoor heat exchanger 
temperature sensor open 
or short circuit 

  Indoor heat exchanger 

temperature sensor lead wire 
and connector 

H24 

Indoor heat 
exchanger 
temperature sensor 
2 abnormality 

Continuous for 5s 

— 

Indoor heat exchanger 
temperature sensor 2 open 
or short circuit 

  Indoor heat exchanger 

temperature sensor 2 lead wire 
and connector 

H27 

Outdoor air 
temperature sensor 
abnormality 

Continuous for 5s 

— 

Outdoor air temperature 
sensor open or short circuit 

  Outdoor air temperature sensor 

lead wire and connector 

H28 

Outdoor heat 
exchanger 
temperature sensor 
1 abnormality 

Continuous for 5s 

— 

Outdoor heat exchanger 
temperature sensor 1 open 
or short circuit 

  Outdoor heat exchanger 

temperature sensor 1 lead wire 
and connector 

H30 

Outdoor discharge 
pipe temperature 
sensor abnormality 

Continuous for 5s 

— 

Outdoor discharge pipe 
temperature sensor open 
or short circuit 

  Outdoor discharge pipe 

temperature sensor lead wire 
and connector 

H32 

Outdoor heat 
exchanger 
temperature sensor 
2 abnormality 

Continuous for 5s 

— 

Outdoor heat exchanger 
temperature sensor 2 open 
or short circuit 

  Outdoor heat exchanger 

temperature sensor 2 lead wire 
and connector 

H33 

Indoor / outdoor 
misconnection 
abnormality 

— — 

Indoor and outdoor rated 
voltage different 

  Indoor and outdoor units check 

H35 

Indoor drain water 
adverse current 
abnormal 

— — 

— 

— 

H36 

Outdoor gas pipe 
temperature sensor 
abnormality 

Continuous for 5s 

Heating 
protection 
operation only 

Outdoor gas pipe 
temperature sensor open 
or short circuit 

  Outdoor gas pipe temperature 

sensor lead wire and connector 

H37 

Outdoor liquid pipe 
temperature sensor 
abnormality 

Continuous for 5s 

Cooling 
protection 
operation only 

Outdoor liquid pipe 
temperature sensor open 
or short circuit 

  Outdoor liquid pipe temperature 

sensor lead wire and connector 

H38 

Indoor/Outdoor 
mismatch (brand 
code) 

— 

— 

Brand code not match 

  Check indoor unit and outdoor 

unit 

H39 

Abnormal indoor 
operating unit or 
standby units 

3 times happen 
within 40 minutes 

— 

Wrong wiring and 
connecting pipe, expansion 
valve abnormality, indoor 
heat exchanger sensor 
open circuit 

 Check indoor/outdoor 

connection wire and connection 
pipe 

  Indoor heat exchanger sensor 

lead wire and connector 

  Expansion valve and lead wire 

and connector 

 
 
 

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H41 

Abnormal wiring or 
piping connection 

— — 

Wrong wiring and 
connecting pipe, expansion 
valve abnormality 

 Check indoor/outdoor 

connection wire and connection 
pipe 

  Expansion valve and lead wire 

and connector 

H64 

Outdoor high 
pressure sensor 
abnormality 

Continuous for 1 
minutes 

— 

High pressure sensor open 
circuit during compressor 
stop 

  High pressure sensor 

  Lead wire and connector 

H97 

Outdoor fan motor 
mechanism lock 

2 times happen 
within 30 minutes 

— 

Outdoor fan motor lock or 
feedback abnormal 

  Outdoor fan motor lead wire 

and connector 

  Fan motor lock or block 

H98 

Indoor high pressure 
protection 

— — 

Indoor high pressure 
protection (Heating) 

  Check indoor heat exchanger 

  Air filter dirty 

  Air circulation short circuit 

H99 

Indoor operating unit 
freeze protection 

— — 

Indoor freeze protection 
(Cooling) 

  Check indoor heat exchanger 

  Air filter dirty 

  Air circulation short circuit 

F11 

4-way valve 
switching 
abnormality 

4 times happen 
within 30 minutes 

— 

4-way valve switching 
abnormal 

 4-way valve 

  Lead wire and connector 

F17 

Indoor standby units 
freezing abnormality 

3 times happen 
within 40 minutes 

— 

Wrong wiring and 
connecting pipe, expansion 
valve leakage, indoor heat 
exchanger sensor open 
circuit 

 Check indoor/outdoor 

connection wire and pipe 

  Indoor heat exchanger sensor 

lead wire and connector 

  Expansion valve lead wire and 

connector 

F90 

Power factor 
correction 
(PFC) circuit 
protection  

4 times happen 
within 10 minutes 

— 

Power factor correction 
circuit abnormal 

  Outdoor PCB faulty 

F91 

Refrigeration cycle 
abnormality 

2 times happen 
within 20 minutes 

— 

Refrigeration cycle 
abnormal 

  Insufficient refrigerant or valve 

close 

F93 

Compressor 
abnormal revolution 

4 times happen 
within 20 minutes 

— 

Compressor abnormal 
revolution 

  Power transistor module faulty 

or compressor lock 

F94 

Compressor 
discharge overshoot 
protection 

4 times happen 
within 30 minutes 

— 

Compressor discharge 
pressure overshoot 

  Check refrigeration system 

F95 

Outdoor cooling high 
pressure protection 

4 times happen 
within 20 minutes 

— 

Cooling high pressure 
protection 

  Check refrigeration system 

  Outdoor air circuit 

F96 

Power transistor 
module overheating 
protection 

4 times happen 
within 30 minutes 

— 

Power transistor module 
overheat 

 PCB faulty 

  Outdoor air circuit (fan motor) 

F97 

Compressor 
overheating 
protection 

3 times happen 
within 30 minutes 

— Compressor 

overheat 

 Insufficient refrigerant 

F98 

Total running current 
protection 

3 times happen 
within 20 minutes 

— Total 

current 

protection 

  Check refrigeration system 

  Power source or compressor 

lock 

F99 

Outdoor direct 
current (DC) peak 
detection 

Continuous 
happen for 7 times 

— 

Power transistor module 
current protection 

  Power transistor module faulty 

or compressor lock