Operation CHARM: Car repair manuals for everyone.

Refrigerant Pressure Sensor / Switch: Description and Operation

1. Function
It plays a role to control compressor magnetic clutch when it operates unusual low pressure in A/C system.




2. Operation
- When the S/W contact are open
The compressor magnetic clutch coil is de-energized, the A/C clutch is disengaged and the compressor does not operate. Because, the electrical S/W contacts are normally open when the suction pressure is approximately 157 kPa.

- When the S/W contact are closed
The compressor magnetic clutch coil is de-energized, the A/C clutch is engaged to drive the compressor. The electrical S/W contacts will close when the suction pressure rises to approximately 324 kPa (47 psi).