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Only training and service purposes.
Connect manifold gauge to the service valve of Compressor Module, and compare the output of high pressure
sensor to the output of low pressure sensor to detect the defect.
below) Compare the output of pressure sensor to the output of manifold gauge pressure using the table below.
Read the pressure clearly between black and white as the composition of pressure sensor.
1) If the pressure of manifold gauge is 0~1kg/cm
2
, it indicates the pressure got lower due to the leakage of refriger-
ant. Find the place of leakage and fix it.
2) If the difference of the outputs of high and low pressure is in the range of 1kg/cm
2
, the pressure sensor is normal.
3) If the difference of the outputs of high and low pressure is over 1kg/cm
2
, the pressure sensor is out of order, it
need to be replaced.
4) The composition of pressure sensor
The pressure sensor is composed like the circuit picture shown above. If DC 5V voltage flows on red and black
wire, voltage would be made between the white and black wire. The pressure which is equivalent to the pressure
output is shown in the table above.
1) The outdoor fan is controlled by the inverter motor which can control the number of rotations.
2) The outdoor fan is controlled by the high/low pressure of the Compressor Module after the operation of com-
pressor.
3) There is possibility that the outdoor fan does not operate due to low capacity operation or low outdoor tempera-
ture even if the compressor is operating. This does not mean breakdown of the unit, the fan will start operating if
it reaches the set point.
2.6 Pressure Sensor(High/Low Pressure Sensor)
2.7 Outdoor Fan
<Low Pressure Sensor>
<High Pressure Sensor>
OUTPUT CHARACTERISTICS
OUTPUT CHARACTERISTICS
High Pressure Sensor : 0~5MPa
Vout
0.5~3.5V
Low Pressure Sensor : 0~2MPa
Vout
0.5~3.5V
(Red)
(Black)
(White)
±5%
Pressure
sensor
Checking Method for Key Components
