Refrigerant Circuit Pressures And Temperatures

The pressures and temperatures in the refrigerant circuit depend on the current operating conditions (such as engine RPM, coolant fan level 1, 2 or 3, engine temperature, A/C compressor on or off) as well as on the effects of outside influences (such as outside temperature, humidity, desired cooling output).

In vehicles with A/C Compressor Regulator Valve -N280-, the pressure is modified on the low pressure side by the valve.

For this reason, values indicated in the following table are valid only as reference points. They are attained at an engine speed of 1, 500 to 2, 000 RPM and an ambient temperature of 20 °C (68 °F) after about 20 minutes.

The connections provided for measuring pressure for the manometer battery are located in the vehicle-specific refrigerant circuit.

Refer to AIR CONDITIONING .

At 20 °C (68 °F) with the engine not running, the pressure in the refrigerant circuit is 4.7 bar (68.17 psi). Refer to REFRIGERANT R134A VAPOR PRESSURE TABLE .