Refrigerant Pressure Sensor / Switch: Description and Operation

REFRIGERANT PRESSURE SENSOR









The refrigerant pressure sensor is installed at the liquid tank of the air conditioner system. The sensor uses an electrostatic volume pressure transducer to convert refrigerant pressure to voltage. The voltage signal is sent to ECM, and ECM controls cooling fan system.


The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sensor, located on the condenser.

If the system pressure rises above, or falls below the specifications, the refrigerant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM.

ECM makes the A/C relay go OFF and stops the compressor when pressure on the high pressure side detected by refrigerant pressure sensor is over about 2,746 kPa (28 kg/sq.cm, 398 psi), psi or below about 177 kPa (1.8 kg/sq.cm, 26 psi).