V6R VRF 50Hz
125
P
art
6
- Di
agno
si
s and
Tr
ou
bles
ho
o
ting
Procedure
P1
ODU stop valves are closed
Yes
Open the stop valves
No
High pressure sensor connection on
outdoor main PCB is loose
1
Yes
Ensure the sensor is connected properly
No
High pressure sensor has short-circuited
or failed
2
Yes
Replace the sensor
No
Excess refrigerant
3
Yes
Discharge part of the refrigerant. Add oil
if it leaks during discharge
No
System contains air or nitrogen
4
Yes
Flush all refrigerant then vacuum the
system and recharge the refrigerant. Add
oil to the system if it leaks
No
The high pressure side is blocked, caused
by crushed or bent pipe or blocked EEV
5
Yes
Inspect the system and fix the error
No
The condenser heat exchange is poor
6
Yes
Inspect the system and fix the error
No
Replace the outdoor main PCB
Notes:
1.
The high pressure sensor connection is port CN17 on the outdoor main PCB.
2.
Measure the resistance among the three terminals of the pressure sensor. If the resistance is of the order of mega Ohms or infinite, the pressure sensor has
failed.
3.
Excess refrigerant causes discharge temperature to be lower than normal, discharge pressure to be higher than normal and suction pressure to be higher
than normal.
4.
Air or nitrogen in the system causes discharge temperature to be higher than normal, discharge pressure to be higher than normal, compressor current to
be higher than normal, abnormal compressor noise and an unsteady pressure meter reading.
5.
High pressure side blockage causes discharge temperature to be higher than normal, discharge pressure to be higher than normal and suction pressure to
be lower than normal.
6.
In cooling mode check outdoor heat exchangers, fans and air outlets for dirt/blockages. In heating mode check indoor heat exchangers, fans and air outlets
for dirt/blockages.