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15.5.19 F11 (4-way valve Abnormality)
Malfunction Decision Conditions
When indoor heat exchanger is cold during heating (except deice) or when indoor heat exchanger is hot during
cooling and compressor operating, the 4-way valve is detected as malfunction.
Malfunction Caused
Indoor heat exchanger (pipe) thermistor
4-way valve malfunction
Troubleshooting
* Check gas side pipe – for hot gas flow in cooling mode
YES
YES
YES
NO
NO, it happen in cooling/dry as well
NO
Outdoor PCB fault
● Replace
Outdoor
PCB
No
Good
● Reconnect CN-HOT
(4-way valve connector)
No
Good
● Attach and screw the V-coil
to solenoid valve
No
continuity
(open)
Remove CN-HOT.
Measure continuity
of the coil
V-coil fault
● Replace
V-coil
only
Reverse solenoid valve faulty
● Replace the 4-way valve
Outdoor PCB fault
● Replace Outdoor PCB
No supply
OK
OK
OK
When abnormality starts again
Check the indoor pipe temperature
thermistor:
● Plug out connector (CN-TH) from the
indoor unit PCB
● Measure the resistance of the indoor
heat exchanger temperature thermistor
The 4-way valve may have been damaged
or wrongly connected between discharge
and suction tube
● Check connecting tubes to 4-way valve
Is the measured resistance of the indoor
pipe temperature thermistor matches the
value specified in its characteristic chart?
Problem occurs in heating mode only?
● Defect in indoor pipe temperature
thermistor
● Replace the indoor pipe temperature
thermistor
Is 4-way solenoid valve being energised?
4-way valve not working
(not energize)
Check CN-HOT
connection
(4-way valve connector)
Check V-coil attach to
solenoid valve
Check valve v-coil
continuity
Measure voltage
supplied to CH-HOT at
the start of heating
For safety reason and to prevent component
breakdown, always switch off the power before
remove and connect the component.
OK (Depending on 4-way valve model)
YELLOW
2
1
COIL COMPLETE
CN-HOT
(WHT)
YELLOW
4 WAYS VALVE
CN-HOT
(VH9-2)
4 WAYS
VALVE
3
2
1
Caution
