Pressure Sensor(High/Low Pressure Sensor); Outdoor Fan - LG MULTI V Service Manual

Checking Method for Key Components

2.5 Pressure Sensor(High/Low Pressure Sensor)

Connect manifold gauge to the service valve of outdoor unit, 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.
<Low Pressure Sensor>
OUTPUT CHARACTERISTICS
1) If the pressure of manifold gauge is 0~1 kg/cm
erant. 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 1 kg/cm
3) If the difference of the outputs of high and low pressure is over 1 kg/cm
need to be replaced.
4) The composition of pressure sensor
High Pressure Sensor : 0~5 MPa
Pressure
sensor
Low Pressure Sensor : 0~2 MPa
The pressure sensor is composed like the circuit picture shown above. If DC 5 V 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.

2.6 Outdoor Fan

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 outdoor unit after the operation of compressor.
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 , it indicates the pressure got lower due to the leakage of refrig-
Vout 0.5~3.5 V
Vout 0.5~3.5 V
(Red) VC,
DC 5 V±5 %
(White)
(Black)
<High Pressure Sensor>
OUTPUT CHARACTERISTICS
2 , the pressure sensor is out of order, it
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2 , the pressure sensor is normal.