Operation CHARM: Car repair manuals for everyone.

Refrigerant System Protection





REFRIGERATION SYSTEM


Refrigerant System Protection


REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sensor, located on the liquid tank. 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.
The ECM then signals the BCM (via CAN communication lines) to cease suppling power to the A/C relay which disengages and stops the compressor. This occurs when pressure on the high pressure side (as detected by refrigerant pressure sensor) is over approximately 2,746 kPa (28 kg/cm2, 398 psi), or below approximately 120 kPa (1.22 kg/cm2, 17.4 psi).

PRESSURE RELIEF VALVE
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the refrigerant pressure in the system increases to an abnormal level [more than 3,600 kPa (36.7 kg/cm2, 522 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the atmosphere.