Daikin VRV II-Q RQYQ8-48PY1B Service Manual page 119

SiBE341027
Troubleshooting
Note:
*1: Make a comparison between the voltage of the pressure sensor and that read by the
*2: Make measurement of voltage of the pressure sensor.
Micro-controller
Service Diagnosis
Be sure to turn off power switch before connect or disconnect connector,
Caution
or parts damage may be occurred.
Is the stop
valve opened?
(1) Mount a pressure gauge on the low pressure
service port.
(2) Reset the operation using the remote
controller, and then restart the operation.
Are the
characteristics of
the low pressure
sensor normal?
(*1)
Service Checker
Connect the service checker to compare the "low pressure"
value and the actual measurement value by pressure
sensor (*1) by using the service checker.
Check if the "low
pressure" value and
the actual
measurement value
by pressure sensor
are the same.
· The low pressure sensor is normal, and the pressure
detected with the PCB is also normal.
· The low pressure has really become low.
Remove the causes by which the low pressure has
CHECK 2
become low.
pressure gauge.
(As to the voltage of the pressure sensor, make measurement of voltage at the connector,
and then convert it to pressure.)
A/D input
Make measurement of DC voltage between these wires.
CHECK 2 Refer to P.180
NO
YES
NO
YES
NO
YES
+5V
Connector for low pressure sensor
(Blue)
(4)
(3)
(2)
(1)
Troubleshooting by Remote Controller
Open the stop valve.
Replace the low pressure sensor.
Replace the outdoor unit main
PCB (A1P).
Red
Black
Low
pressure
sensor
White
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