Daikin RMXS-L Series Service Manual page 194

Troubleshooting for Outdoor Unit
Troubleshooting
Check No.30
Refer to P.220
185
Be sure to turn off the power switch before connecting or disconnecting
Caution
connectors, or parts may be damaged.
Check for the points shown below.
(1) Is the stop valve open?
(2) Is the high pressure switch connector properly connected to the main PCB (A1P)?
(3) Does the high pressure switch have continuity?
Are the
three points above
OK?
YES
(1) Mount a pressure gauge on the high pressure service port.
(2) Reset the operation using the remote controller, and then restart the operation.
Does the stop
E3
due to malfunction ( )
recur?
NO
Are the
characteristics of the
high pressure sensor
normal? (See ∗1.)
YES
Service Checker
Connect the service checker to compare the high pressure value and the actual measurement
value by pressure sensor by using the service checker. (See ∗2)
Are
the high pressure
value and the actual
measurement value by
pressure sensor
the same?
YES
· The high pressure sensor is normal, and the pressure detected with the PCB is also normal.
· The high pressure has really become high.
Remove the causes by which the high pressure has become high.
Check No.30
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 226.)
2: Measure the voltage of the pressure sensor.
GND
Microcomputer
A/D input
Measure the voltage here.
NO
Is the
high pressure
YES
switch operating value
normal (4.0 MPa
(1338 ftAq))?
YES
NO
NO
+5V
X17A (Red)
(4)
(3)
(2)
(1)
SiUS181305E
Rectify the defective points.
NO
Replace the high pressure switch.
Replace the high pressure sensor.
Replace the main PCB (A1P).
Red
Black
High
pressure
sensor
White
Troubleshooting
(R19092)
(R19189)