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19
TROUBLESHOOTING
For ease of service, the systems are equipped with diagnostic code
display LEDs on both the indoor and outdoor units. The outdoor
diagnostic display consists of two LEDs (Red and Green) on the
outdoor unit board and is limited to a few errors. The indoor
diagnostic display is a combination of flashing LEDs on the
display panel or the front of the unit. If possible, always check the
diagnostic codes displayed on the indoor unit first.
The diagnostic codes displayed in the indoor and outdoor units are
listed in the tables below.
INDOOR UNIT DIAGNOSTIC GUIDES
Table 7—Indoor Unit Diagnostic Guides
Operation Lamp
Timer Lamp
Display
LED Status
☆
1 time
X
E0
Indoor unit EEPROM error
☆
2 times
X
E1
Communication malfunction between indoor and outdoor units
☆
4 times
X
E3
Indoor fan speed has been out of control
☆
5 times
X
E4
Indoor room temperature sensor T1 open circuit or short circuit
☆
6 times
X
E5
Evaporator coil temperature sensor T2 open circuit or short circuit
☆
7 times
X
EC
Refrigerant leakage detection
☆
8 times
X
EE
Water---level alarm malfunction
☆
1 time
O
F0
Current overload protection
☆
2 times
O
F1
Open circuit or short circuit of outdoor ambient temperature sensor T4
☆
3 times
O
F2
Open circuit or short circuit of condenser coil temperature sensor T3
☆
4 times
O
F3
Open circuit or short circuit of Compressor discharge temperature sensor T5
☆
5 times
O
F4
Outdoor unit EEPROM error
☆
6 times
O
F5
Outdoor fan speed has been out of control
☆
7 times
O
F6
T2B sensor error
☆
8 times
O
F7
Lifting---panel communication error
☆
9 times
O
F8
Lifting---panel malfunction
☆
10 times
O
F9
Lifting---panel is not closed
☆
1 time
☆
P0
IPM malfunction
☆
2 times
☆
P1
Over voltage or over low voltage protection
☆
3 times
☆
P2
High temperature protection of compressor top
☆
4 times
☆
P3
Outdoor low temperature protection
☆
5 times
☆
P4
Inverter compressor drive error
☆
6 times
☆
P5
Mode conflict
☆
7 times
☆
P6
Compressor low---pressure protection
☆
8 times
☆
P7
Outdoor IGBT temperature sensor error
O (light) X (off)
☆
(
flash
)
For additional diagnostic information, refer to the
Service Manual.
OUTDOOR UNIT DIAGNOSTIC GUIDES
Table 8—Outdoor Unit Diagnostic Guides
LED2
LED1
Indoor Unit display
Failure Mode
(Green)
(Red)
O
X
Standby, normal
X
O
Operation, normal
O
☆
E5
Compressor drive board EEPROM error
☆
X
P0
IPM malfunction or IGBT over---strong current protection
O
O
P1
Over voltage or too low voltage protection
X
☆
P4
Inverter compressor drive error
☆
O
P4
Inverter compressor drive error
☆
☆
P4
Communication malfunction between main control board and driver board
☆
= Flashing, X = Off
For additional diagnostic information, refer to the Service Manual