Troubleshooting MCAC-UTSM-2008-05
66 Outdoor Units
9. P4 malfunction
LED indicates P4
Compressor discharge temperature protection
Check whether the compressor discharge temp. more than 115°C ?
No
Check whether the wiring connection is right
between compressor discharge temp.
sensor and PCB according to wiring
diagrams
Yes
Validate: Check whether the resistance of compressor
discharge temp. sensor is right refer to the Annex 2
No
Correct the wiring connection
Yes
Replace outdoor main board
Judge: The discharge temp. sensor is broken
No
Replace the compressor
discharge temp. sensor
Check whether the refrigerant is leakage
Stop leaking and add refrigerant
Yes
Yes
To Next Page
Loading...
