Air conditioning system with refrigerant R134a

Pressures and temperatures in the refrigerant circuit

~1min read

WARNING When working on the refrigerant circuit, observe generally applicable safety rules and the Regulations for Pressure Tanks.
The pressures and temperatures in the refrigerant circuit depend on the momentary operating conditions (e.g. engine speed, speed 1, 2, or 3 of radiator fan, engine temperature, whether air conditioner compressor is on or off) as well as environmental influences (e.g. ambient temperature, humidity, required cooling output). In vehicles with air conditioner compressor regulating valve -N280-, the pressure on the low-pressure side is varied by activating the valve. Therefore, the values given in the following tables may only be considered as guidelines. They occur at an engine speed of 1,500 to 2,000 rpm and an ambient temperature of 20 °C after about 20 minutes. The locations of connections provided for pressure measurements can be found in the vehicle-specific coolant circuits.

→ Rep. gr.87

At 20 °C and with the engine stopped, the refrigerant circuit will adjust itself to a pressure of 4.7 bar positive pressure → Chapter.

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