Haier HSU-22HVA103/R2(DB) - 7.2.8 Communication error between the indoor and outdoor units

NO
NO
7.2.7 The EEPROM Abnormality ( Indoor or outdoor unit)
Indoor Display E4: ：Indoor EEPROM error
F12：Outdoor EEPROM error
Method of the Data detected by the EEPROM are used to determine MCU
Malfunction
Detection
Malfunction
when the Data of EEPROM is error or the EEPROM is damaged
Decision
Conditions
Supposed ■
Faulty EEPROM data
Causes ■ Faulty EEPROM
■ Faulty PCB
Troubleshooting
* Caution Be sure to turn off power switch before connect or disconnect connector, or
parts damage may be occurred.
YES
NO
the results deviate
much?
YES
The sensor is damaged. Replace the sensor with a new
one.
The outdoor mainboard is damaged and needs be
re
placed
Check whether LED1 on
the outdoor unit blinks 1
times
The outdoor mainboard
is damaged. Replace i
t
with a new one.
the indoor mainboard is
damaged, and needs
replacing with a new one
HSU-18,22HVA103/R2(DB) Service Diagnosis
83
Domestic Air Conditioner