Midea ATOM B Series Service Manual page 83

Atom B Series VRF 50/60Hz
2.23.9 L1: DC bus low voltage protection
Voltage of power supply is 166-265V?
Check the wiring between main control board and
filter board is correct or not.
Repower on and waiting for 10S,and then test the
voltage of CN4 port "RL" and "12V" port to check
whether their voltage is DC 12V
Replace outdoor filter board
2.23.10 L2: DC bus high voltage protection
Voltage of power supply is 166-265V?
Replace outdoor main PCB
82
L1
Yes
Yes
Yes
L2
No
Provide normal power supply
No
No
Replace outdoor main PCB
No
Provide normal power supply
Connect again