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SG-38MARB-01 Specifications subject to change without notice.
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INDOOR UNIT DIAGNOSTIC GUIDES
Table 18 — Indoor Unit Diagnostic Guide
O(light) X(off)
(flash)
NOTES:
P3
1. In the
HEATING
mode, when the outdoor temperature is lower than -25 °C for one hour, the indoor unit displays the error code
P3
. If the
outdoor temperature is higher than -22°C for 10 minutes and the compressor stops for 1 hour or the outdoor temperature is higher than -5°C for
10 minutes, the unit will start.
P6
2. Low pressure protection switch is open. Check the switch and repair or leak check the unit and recharge.
Troubleshooting
Use the remote controller. If the unit does not respond to the remote, the indoor PCB needs to be replaced; if the unit does respond, then the
display board needs to be replaced.
OPERATION LAMP TIMER LAMP DISPLAY
LED STATUS
SOLUTION
1 time
X
EH 00/
EH 0A
Indoor unit EEPROM parameter error
--
2 times
X
EL 01
Indoor / outdoor units communication error
3 times
X
EH 02
Zero-crossing signal detection error
4 times
X
EH 03
The indoor fan speed is operating outside of the normal control
5 times
X
EC 51
Outdoor unit EEPROM parameter error
5 times
X
EC 52
Condenser coil temperature sensor T3 is an open circuit or has short circuited
--
5 times
X
EC 53
Outdoor room temperature sensor T4 is an open circuit or has short circuited
5 times
X
EC 54
Compressor discharge temperature sensor TP is an open circuit or has short
circuited
--
5 times
X
EC 56
Evaporator coil outlet temperature sensor T2B is an open circuit or has short
circuited (for free-match indoor units)
--
6 times
X
EH 60
Indoor room temperature sensor T1 is an open circuit or has short circuited
6 times
X
EH 61
Evaporator coil middle temperature sensor T2 is an open circuit or has short
circuited
--
12 times
X
EC 07
The outdoor fan speed is operating outside of the normal range
9 times
X
EH 06
Indoor PCB/Display board communication error
8 times
X
EL 0C
Refrigerant leakage detection
7 times
PC 00
IPM malfunction or IGBT over-strong current protection
2 times
PC 01
Over voltage or over low voltage protection
3 times
PC 02
Top temperature protection of the compressor or high temperature protection of
the IPM module or high pressure protection
5 times
PC 04
Inverter compressor drive error
1 time
PC 08
Current overload protection
6 times
PC 40
Communication error between the outdoor main chip and the compressor driven
chip
7 times
PC 03
Low pressure protection
1 time
O
--
Indoor units mode conflict (match with multi outdoor unit)
--