Midea MLCAC-UTSM-2010-10, Service Manual

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Troubleshooting MLCAC-UTSM-2010-10
88 Outdoor Units
8. P1 malfunction
P1 display
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
Yes
No
Connect it well
Method: Short connect the high pressure switch socket, check
whether the system can run normally
Yes
Replace high pressure switch
No
Check whether the refrigerant system is ok
Replace outdoor main board
No
Judge 3: Check whether the outdoor ambient temperature is too high
Yes
Stop the unit
No
Judge 4: Check whether the outdoor unit is bad ventilation
Yes
Make the outdoor unit ventilate well
No
Judge 5: Check whether the heat exchanger is dirty
Yes
Clean the heat exchanger
No
Judge 6: Check whether the refrigerant pipe is blocked
Yes
Let the refrigerant out, then use the high pressure
nitrogen or refrigerant to blow pipe, vacuumize and
charge the refrigerant again