Midea MIV V4+ Mini Service Manual page 40

MIV V4+ Mini DC Inverter R410A (220V, 8 kW)
7) P1 malfunction
High pressure protection
Judge 1: Whether the wiring between the high pressure switch
and main control board is connected well or correctly
Judge 2: Whether the high pressure switch is broken
Validate: Short connect the high pressure switch
socket, check whether the system can run normally
Check whether the refrigerant system is ok
Judge 3: Check whether the outdoor ambient temperature is too high
Judge 4: Check whether the outdoor unit is bad ventilation
Judge 5: Check whether the heat exchanger is dirty
Judge 6: Check whether the refrigerant pipe is
blocked
Replace outdoor main board
38
LED indicates P1
Yes
No
No
No
No
No
No
Connect it well
Yes
Replace high pressure switch
Yes
Yes
Make the outdoor unit ventilate well
Yes
Clean the heat exchanger
Yes
Drop refrigerant, then use the high pressure
nitrogen or refrigerant to blow pipe,
vacuumize and add the refrigerant again
DM12-01.01.05en
Stop the unit
Outdoor units