Service Manual

Troubleshooting for Outdoor Unit SiUS181631EA
230 Troubleshooting
Troubleshooting
Check No.31
Refer to P.264
∗
1: Compare the voltages of the pressure sensor and the pressure gauge.
(For the voltage of the pressure sensor, measure the voltage at the connector, and then convert
it to pressure, referring to page 269.)
∗
2: Measure the voltage of the pressure sensor.
NO
YES
NO
YES
YES
Is the stop valve open?
Open the stop valve.
(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? (See ∗1.)
Check if
the low pressure
value and the actual
measurement value
by pressure sensor
are the
same.
Replace the low pressure sensor.
· 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 become low.
Replace the main PCB (A1P).
NO
Service Checker
Connect the service checker to compare the low pressure
value and the actual measurement value by pressure
sensor by using the service checker. (See ∗2)
Check No.31
(R15632)
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
+5V
GND
(4)
(3)
(2)
(1)
Microcomputer
A/D input
Measure the voltage here.
X18A (Blue)
Red
Black
White
Low
pressure
sensor
(R15587)