Operation Manual

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Malfunction
Error code
Reason
Solution
Software control
exception
EE21
1.Compressor runs out of step
2. Wrong program
3. Impurity inside compressor causes
the unstable rotate speed
1. Check the main board or
change a new one
2. Enter correct program
Current detection circuit
failure
EE22
1. Voltage signal abnormal
2. Driver board is damaged
1. Check the main board or
change a new one
2. Change a new driver board
Compressor start failure
EE23
1. Main board is damaged
2. Compressor wiring error or poor
contact or unconnected
3. Liquid accumulation inside
4. Wrong phase connection for
compressor
1. Check the main board or
change a new one
2. Check the compressor
wiring according to the circuit
diagram
Check the compressor or
change a new one
Ambient Temperature
device failure on Driver
board
EE24
Ambient Temperature device failure
Change driver board or main
board
Compressor phase
failure
EE25
Compressors U, V, W are connected
to one phase or two phases.
Check the actual wiring
according to the circuit diagram
Four-way valve reversal
failure
EE26
1. Four-way valve reversal failure
2. Lack of refrigerant (no detect
when T3 or T5 malfunction)
1. Switch to Cooling mode to
check the 4-way valve if it has
been reversed correctly
2. Change a new 4-way valve
3. Fill with gas
EEPROM data read
malfunction
EE27
1. Wrong EEPROM data in the
program or failed input of EEPROM
data
2. Main board failure
1. Re-enter correct EEPROM
data
2. Change a new main board
The inter-chip
communication failure
on the main control
board
EE28
Main board failure
1. Turn off electricity supply
and restart it
2. Change a new main board
8. Troubleshooting