Daikin VRVIII-S, Service Manual

Page: 176 / 266

SiENBE34-703 Troubleshooting by Indication on the remote control
Troubleshooting 165
Troubleshooting
∗
2: Voltage measurement point
∗
1: Refer to “Thermistor Resistance / Temperature Characteristics” table on P225.
∗
2: Refer to “Pressure Sensor, Pressure / Voltage Characteristics” table on P227.
(V2819)
The
suction pipe1
temp. minus low
pressure saturation temp.
is 20 °Cor higher.
Resistance
is normal when
measured with the
thermistor (R3T) for
suction pipe1 disconnected
from the outdoor unit
PC board.
∗
1
Out of gas or refrigerant
system is clogged. Requires
check of refrigerant system.
Replace the thermistor.
Replace the outdoor unit PC
board (A1P).
Out of gas, closing of stop
valve or refrigerant system is
clogged. Requires check of
refrigerant system.
Replace main outdoor unit
PC board (A1P).
Is the low
pressure sensor
correct?
Replace the low pressure
sensor.
Cooling
Low pressureis 0.25
MPaor less.
The
voltage of
X18A pins (2) and
(3) on main outdoor unit
PC board (A1P) is 1.0 VDC or
less. (Low pressure sensor
output voltage)
∗
2
Replace low pressure sensor.
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Caution
YES YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
4
3
2
1
(V2809)
Microcomputer
A/D input
Red
Black
White
GND
*2 Measure DC voltage here.
Lo
w pressure sensor
Outside unit PC board A2P
+5V
X45A