Daikin VRV III REYQ8PY1 Service Manual page 265

Troubleshooting by Indication on the Remote Controller
Troubleshooting
254
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
Is the stop
valve open?
Mount a pressure gauge on the low-pressure
service port.
Reset the operation using the remote controller,
and then restart the operation.
Are the
characteristics of the
low pressure sensor
normal?
(See ∗1.)
Service Checker
Connect the service checker to compare the "low pressure"
value and the actual measurement value by pressure sensor
(Refer to ∗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 PC board is also normal.
· The low pressure has really become low.
Referring to information on P351, remove the
CHECK 6
causes by which the low pressure has become low.
∗1: Make a comparison between the voltage of the pressure sensor and that read by the
pressure gauge.
(As to the voltage of the pressure sensor, make measurement of voltage at the
connector, and then convert it to pressure according to information on P419.)
∗2: Make measurement of voltage of the pressure sensor.
Micro controller
A/D input
Make measurement of DC voltage between these wires.
NO
YES
NO
YES
NO
YES
+5V
Connector for low pressure sensor
(Blue)
(4)
(3)
(2)
(1)
Si37-701
Open the stop valve.
Replace the low pressure sensor.
Replace main PC board
(A1P).
Red
Black
Low
pressure
White sensor
Troubleshooting