Activation Of Low Pressure Sensor - Daikin RXQ12AHR Service Manual

SiAF341904E

5.24 Activation of Low Pressure Sensor

Applicable All outdoor unit models
Models
E4
Error Code
Method of Error Make judgment of pressure detected by the low pressure sensor with the outdoor unit main
Detection PCB.
Error Decision
When low pressure caused a drop while the compressor is in operation:
Conditions  Operating pressure: 0.07 MPa
Supposed
 Abnormally drop in low pressure
Causes  Defective low pressure sensor
 Defective outdoor unit main PCB
 The stop valve is not opened
Troubleshooting
Note(s)
1. Make a comparison between voltage measured by the pressure sensor and that read by the
pressure gauge.
(The pressure sensor makes measurement of voltage at its connector block to convert it to
pressure. CHECK 12)
Part 6 Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Is the stop
valve open?
YES
(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?
(∗1)
YES
Service Checker CHECK 12
Connect the Service Checker, and then make a comparison between "low
pressure" checked by the Service Checker and the measurement of the low
pressure sensor. (∗1)
Is the
"low pressure"
checked by the
Service Checker same
as the measurement of
the low pressure
gauge?
YES
- The low pressure sensor is normal, and pressure detection with the
outdoor unit main PCB is also normal.
- The low pressure has really become low.
CHECK 2 Eliminate factors that cause the low pressure to decrease.
Troubleshooting by Error Code
NO
Open the stop valve.
NO
Replace the low pressure sensor
(S1NPL).
NO
Replace the outdoor unit main
PCB (A1P).
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