Midea M2OC-18HFN1-M Service Manual page 85

9.4.2.13 P5(High temperature protection of condenser) error diagnosis and solution.
Error Code
Malfunction decision
conditions
Supposed causes
Trouble shooting:
High temperature protection of
condenser
Check whether the
condenser temperature is
more than 65° C
Yes
Judge 1: Check whether the
outdoor ambient
temperature is higher than
50℃
No
Judge 2: Check whether the
heat exchanger is dirty
No
Judge 3: The refrigerant
pipe is blocked
P5
When outdoor pipe temperature is more than 65° C, the unit will
stop, and unit runs again when outdoor pipe temperature is less
than 52° C
● The condenser temperature sensor faulty
● Heat exchanger dirty
● System block
Replace the temperature sensor
No
Check whether the
resistance of condenser
temp. sensor is correct
refer to the Appendix 1
Yes Stop the unit
Yes Clean the heat exchanger
Let the refrigerant out, then use the high
Yes pressure nitrogen or refrigerant to blow pipe,
vacuumize and charge the refrigerant again
Yes Replace outdoor main board
No