Daikin VRV II-Q RQYQ8-48PY1B Service Manual page 160

Troubleshooting by Remote Controller
Troubleshooting
Note:
*1. Check the low pressure value by using pressure gauge in operation.
*2. Compare the actual measurement value by pressure sensor with the value by the pressure
*3. Compare the thermistor resistance value with the value on the surface thermometer.
150
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
In cooling
Mount a pressure gauge at the service port on the low
pressure side.
Reset the operation using the remote controller then restart.
Is the low pressure
0.1MPa or less? (*1)
YES
In heating
Reset the operation using the remote controller then restart.
Is the temperature
difference between the
suction pipe and the
heat exchanger 20 ˚C
or more?
YES
gauge.
CHECK 2
Refer to P.180
CHECK 3 Refer to P.181
Is the
characteristics of
NO
low pressure
sensor normal?
(*2)
YES
Are the property of suction pipe
NO
thermistor (R8T) and heat
exchanger thermistor (R9T)
normal? (*3)
YES
SiBE341027
NO
Replace the low pressure
sensor.
Replace the outdoor unit
main PCB (A1P).
Remove the factor of
decreasing low pressure.
CHECK 2
NO
Replace the thermistor.
Replace the outdoor unit main
PCB (A1P).
Remove the factor of
superheating.
CHECK 3
Service Diagnosis