Haier · Air Conditioning
This error signifies a problem with the EEPROM (Electrically Erasable Programmable Read-Only Memory) on either the indoor (E4) or outdoor (F12) unit. This memory stores vital operating data.
Click steps to track your progress.
Turn off the power to the unit for at least 1 minute, then power it back on.
If the error persists, the relevant mainboard (Indoor or Outdoor PCB) needs to be replaced by a technician.