P9 Outdoor Unit Fan Motor Stall Protection; P11 High Evaporator Temperature Protection - Omega OTEC IEWB Series Service Manual

Change a new outdoor unit PCB.
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2.4.22 P9 Outdoor unit fan motor stall protection

Please refer to 5.4.5

2.4.23 P11 High evaporator temperature protection

Description: Indoor unit evaporator temperature (T2) is higher than 65℃.
Possible reason:
 Abnormal T2 temperature sensor
 Faulty 4-way valve
 Bad ventilation
 Refrigerant is not enough
Troubleshooting and repair:
a) Measure the resistance of T2 sensor
b) Check the 4-way valve connection. If unit is in heating mode, there is a 220V output in 4-way
valve port.
c) Check if evaporator is too dirty.
d) Confirm the refrigerant volume.
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