WHEN THE AC UNIT WORKS, THE INDOOR UNIT PCB AND OUTDOOR UNIT PCB NEED TO COMMUNICATE CONTINUOUSLY AND CHECK THE STATUS FOR BOTH SIDES. IF THERE IS A COMMUNICATION PROBLEM FOR 2 MINUTES OR MORE, THE AC UNIT WILL STOP WORKING AND SHOWS THE E0 ERROR CODE.
REPAIR:
***ENERGIZE THE AC UNIT AND OBSERVE FOR APPROXIMATELY 10 MINUTES. IF E0 IS ALWAYS DISPLAYED***:
1) CHECK IF THE INDOOR AND OUTDOOR WIRING CONNECTIONS ARE CORRECT. THE TERMINAL L, N AND S(1) SHALL CORRESPOND TO EACH OTHER ON INDOOR AND OUTDOOR UNITS. MEASURE THE VOLTAGE ON OUTDOOR TERMINAL L AND N (BEFORE DISPLAY OF E0 FAULT). IF THE VOLTAGE IS “0”:
SOLUTION 1) REPLACE THE INDOOR MAIN PCB
2) IF THE L & N VOLTAGE IS NORMAL, MEASURE THE VOLTAGE BETWEEN THE OUTDOOR TERMINAL N AND S. IF THE VOLTAGE CHANGE OCCURS BETWEEN 0~24V (PULSATING VOLTAGE):
SOLUTION 2) REPLACE THE INDOOR MAIN PCB
3) IF THE L & N VOLTAGE IS NORMAL, MEASURE THE VOLTAGE BETWEEN THE OUTDOOR TERMINAL N AND S. IF THE VOLTAGE CHANGE OCCURS BETWEEN 0~12V (PULSATING VOLTAGE), BUT THERE IS NO 24V:
SOLUTION 3) REPLACE THE OUTDOOR MAIN PCB
4) IF THE L & N VOLTAGE IS NORMAL, MEASURE THE VOLTAGE BETWEEN THE OUTDOOR TERMINAL N AND S. IF THE VOLTAGE HAS NO CHANGE:
SOLUTION 4) FIRSTLY REPLACE THE INDOOR MAIN PCB. IF THE FAULT REMAINS UNSOLVED, REPLACE THE OUTDOOR PCB
5) INDICATOR ON OUTDOOR PCB:
5.1) THE INDICATOR IS DARK, AND +5V IS NORMAL, TEST VOLTAGE BETWEEN N AND S, IF THERE IS NO 0~24V PULSATING VOLTAGE, PLEASE CHECK R1,R2 WHETHER IT IS OPENED OR SHORTED AFTER SWITCHING OFF THE AIR CONDITIONER:
SOLUTION 5.1) IF YES, REPLACE THE RESISTANCE OR REPLACE OUTDOOR PCB
5.2) THE INDICATOR IS DARK, AND ALSO WITHOUT +5V POWER SUPPLY: SWITCH OFF AIR CONDITIONER, AND INSPECT COMPONENTS AS RECTIFIER BRIDGE—DB101, FAST RECOVERY DIODE—D84, IGBT(Q9) AND IPM(Q1), CHECK WHETHER IT IS BROKEN OR NOT:
SOLUTION 5.2) IF YES, REPLACE THE COMPONENT(S) OR REPLACE OUTDOOR PCB
5.3) IF THERE IS NO DAMAGE AS IN 5.1) AND 5.2), TEST VOLTAGE BETWEEN DC+ AND DC-, IF THE VOLTAGE IS 0V:
SOLUTION 5.3) REPLACE OUTDOOR PCB
6) IF THE PROBLEM CANNOT BE SOLVED BY USING THE METHODS ABOVE:
SOLUTION 6) REPLACE OUTDOOR PCB FIRST. IF THE PROBLEM STILL REMAINS, REPLACE THE INDOOR PCB