ERS EMCH-10W/1, Installation And User Manual

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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.
P3: Over current protection
Check whether the input current is large
than the specific value
Check whether the ambient
temperature is too high
Yes
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.
No
Inspect the system and
fix the error
The refrigerant pipe is block, caused by
crushed or bent pipe, blocked EXV valve,
blocked filter, etc.
PCB is damaged
PCB is damaged, replace PCB
No
Yes
Stop the unit and wait for
ambient temperature get down
Yes
No
Replace PCB
Inspect the system and fix
the error
Yes
No
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