Daikin VRVIII-S Service Manual page 153

Troubleshooting by Indication on the remote control
Troubleshooting
142
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
Is the stop
valve open?
1 Mount a pressure gauge on the low-pressure service port.
2 Connect the Service Checker.
3 Reset the operation using the remote control, and then
restart the operation.
Are the
characteristics of the
low pressure
sensor normal?
(See *1.)
Is the pressure
detected with the
PC board normal?
(See *2.)
· The low pressure sensor is normal, and the pressure
detected with the PC board is also normal.
· The low pressure has really become low.
Refer to information on P.194, remove the causes by
CHECK 2
which the low pressure has become low.
*1: Make a comparison between the voltage of the pressure sensor (*4) 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 P.225.)
*2: Make a comparison between the low pressure value checked with the Service Checker
and the voltage of the pressure sensor (see *1).
*3: Make measurement of voltage of the pressure sensor.
Micro controller
A/D input
Make measurement of DC voltage between these wires. (*4)
NO
YES
NO
YES
NO
YES
+5V
Connector for low pressure sensor
(Blue)
(4)
(3)
(2)
(1)
SiENBE34-703
Open the stop valve.
Replace the low pressure sensor.
Replace the main PCB.
Red
Black
Low
pressure
White sensor
Troubleshooting