THIS IS A PFC OVERCURRENT PROTECTION.
REPAIR:
1) IF THE F5 PROTECTION CODE RANDOMLY APPEARS, IT IS A NORMAL PROTECTION THAT IS CAUSED BY POWER SUPPLY FLUCTUATIONS OR IF THE POWER SUPPLY IS ABNORMAL
2) REPOWER THE AC UNIT. IF THE F5 PROTECTION CODE IS DISPLAYED FREQUENTLY, PLEASE INSPECT THE PFC PROTECTION CIRCUIT OR REPLACE THE OUTDOOR UNIT PCB