18.5.8 P3
When current is over the specific value (Single phase unit 5/7kW 18A, single phase unit 10/12kW 30A, three
phase unit 15A), the system will display P3 protection, the ODU in standby.
When the current goes back to normal range, P3 disappears and normal operation resumes.
Check whether the input current is large
than the specific value
Check whether the ambient
temperature is too high
Low heat exchange efficiency, causes may include
dirty heat exchanger, dirty plate type heat
exchanger, abnormal fan operation, water pump
error, too closed outdoors installation, etc.
The refrigerant pipe is block, caused by
crushed or bent pipe, blocked EXV valve,
blocked filter, etc.
P3: Over current protection
Yes
No
No
No
PCB is damaged
No
PCB is damaged, replace PCB
Yes
Stop the unit and wait for
ambient temperature get down
Yes
Inspect the system and
fix the error
Yes
Inspect the system and fix
the error
Replace PCB
V.2
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