Pressures and Temperatures In Refrigerant Circuit

Pressures And Temperatures In Refrigerant Circuit

CAUTION: When working on the refrigerant circuit, observe generally valid safety precautions and pressure vessel regulations.

The pressures and temperatures in the refrigerant circuit depend on the instantaneous operating statuses (e.g. engine speed, coolant fan speed 1, 2, or 3, engine temperature, compressor on or off) as well as environmental influences (e.g. ambient temperature, humidity, required cooling output).

On vehicles with A/C Compressor Regulator Valve N280 the pressure on the low pressure side is altered by actuating the valve.

For this reason, the values given in the following table are only intended as a rough guide. They are attained at an engine speed of 1500 to 2000 rpm and an ambient temperature of 20 degrees C after about 20 minutes.

Refer to vehicle-specific refrigerant circuit for locations of pressure gauge connections.

At 20 degrees C with the engine not running, the pressure in the refrigerant circuit is 4.7 bar (vapor pressure table).

NOTE: Pressure is measured in different units: 1 MPa (mega pascal) corresponds to 10 bar positive pressure or 145 psi, 1 bar absolute pressure corresponds to 0 bar positive pressure and thus to the ambient pressure (atmospheric pressure).