Midea MIV V4+ Mini, Service Manual

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DM12-01.01.05en MIV V4+ Mini DC Inverter R410A (220V, 8 kW)
Outdoor units 39
8) P2 malfunction
LED indicates P2
Low pressure protection
Judge 1: The wiring between the low pressure switch and
main control board is connected well or correctly
Judge 2: Whether the low pressure switch is broken
Connect it well
Validate: Short connect the low pressure switch
socket, check whether the system can run normally
Check whether the refrigerant system is ok
Yes
No
Judge 3: Check whether the outdoor ambient temperature is too low
Yes
Stop the unit
No
Judge 4: The refrigerant of the system is leakage
Yes
Validate: Connect the pressure gauge to the gauge joint
of the system, check whether the pressure is lower than
0.15MPa
Leak hunting: charge nitrogen or
refrigerant to the system, if the leakage is
serious, there will be distinct gas leakage
“cici” sound; if the leakage is little, use
the suds(mixture of water and abluent is
also ok, if it can make bubble) or
electronic leak detector.
Judge 5: The refrigerant pipe is blocked
Yes
Drop refrigerant, then use the high pressure
nitrogen or refrigerant to blow pipe, vacuumize
and add the refrigerant again
Replace outdoor main board
No
No
Yes
Replace low pressure switch
No