Inspecting The Refrigerant System Sensors - Daikin GYEQ20AN Service Manual

SiAUY361411EA

1.33 Inspecting the Refrigerant System Sensors

Check the continuity between terminals. There should be continuity while stopped.
For each of the high and low refrigerant pressures, get the sensor value and actually measured
value by checking the refrigerant pressure with the outdoor unit's onboard checker and
measuring the refrigerant pressure with a manifold gauge. If the two values are approximately
equal, it means that the refrigerant pressure is normal.
[High pressure sensor]
You can convert the output voltage of the high pressure sensor into the equivalent pressure
using the table on page 226. The input voltage is 5 V (constant) when measured between the
main circuit board's CN4-2 (black) and -3 (red).
[Low pressure sensor]
You can convert the output voltage of the low pressure sensor into the equivalent pressure
using the table on page 226. The input voltage is 5 V (constant) when measured between the
main circuit board's CN4-5 (black) and -6 (red).
Measure the resistance between terminals. If the actually measured value is approximately
equal to the checker value, it means that the sensor is normal.
Measure the resistance between terminals. If the actually measured value is approximately
equal to the checker value, it means that the sensor is normal.
Measure the resistance between terminals. If the actually measured value is approximately
equal to the checker value, it means that the sensor is normal.
Measure the resistance between terminals. If the actually measured value is approximately
equal to the checker value, it means that the sensor is normal.
Parts Inspection
Inspecting the high pressure switch
Working pressure characteristics (factory default settings)
Type
HPS1/2
Inspecting the pressure sensors
High pressure sensor
Low pressure sensor
Inspecting the discharge temperature sensor
Inspecting the intake air temperature sensor
Inspecting the outdoor air temperature sensor
Inspecting the oil temperature sensor
Circuit open Circuit closed
+0
4.0 MPa 3.15±0.15 MPa
-0.15
025958-00X
Pressure range
0 to 4.15 MPa
Connector
(red)
023465-00E
Pressure range
0 to 3.33 MPa
Connector
(white)
023466-00E
Inspecting the Outdoor Unit
198