Gree LSQWRF35VM/NaA-M, Service Manual

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68
Test Operation, Troubleshooting and Maintenance
4.2.2 Flow chart of troubleshooting
(1) High pressure protection
High pressure protection
Does the fan stop
running or run
reversely?
Yes
Check the fan.
Does the electric
expansion valve work
normally?
Is the pressure switch
damaged or is the wiring
loosened ?
Is the finned heat
exchanger too dirty or
aged?
Are water pipes designed
improperly? The flow becomes
smaller when the terminal unit
is turned off.
Is there air inside the
system? (It often occurs
after maintenance.)
Does the controller
alarm incorrectly?
Replace the coils of the
electric expansion valve
or even the main body.
Replace the pressure switch
or rewire it.
Clean the water pipes .
Adjust the water pipes .
Expel air. If necessary,
vacuum the whole system .
If this occurs frequently, the
main board should be
replaced.
Contact the supplier.
No
No
No
No
No
No
No
Yes
No
Yes
Yes
Yes
Yes
Yes