Daikin E-Series Service Manual page 399

Troubleshooting for Outdoor Unit
Troubleshooting
∗
2: Voltage measurement point
∗
1: Refer to "Thermistor Resistance / Temperature Characteristics" table on P405.
∗
2: Refer to "Pressure Sensor, Pressure / Voltage Characteristics" table on P407.
386
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
Cooling
NO
The suction
pipe1 temp. minus
low pressure saturation
temp. is 20 ˚C or
higher.
NO
Resistance
is normal when
measured with the
thermistor (R3T) for suction
pipe1 disconnected from
the outdoor unit PC
board.
∗1
YES
Is the low
pressure sensor
correct?
YES
YES
Low pressure is
0.25 MPa or less.
NO
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
NO
YES
NO
NO
SiAU18-715
YES
Out of gas, closing of stop
valve or refrigerant system
is clogged. Requires
check of refrigerant
YES
Replace main outdoor unit
PC board (A1P).
Replace low pressure
sensor.
Out of gas or refrigerant
system is clogged.
Requires check of
refrigerant system.
Replace the thermistor.
Replace the low pressure
sensor.
Replace the outdoor unit
PC board (A1P).
(Q0575)
Troubleshooting