Volkswagen Golf Quiz
Air conditioning system with refrigerant R134a

Refrigerant circuit with expansion valve

In this manual: Air conditioning system with refrigerant R134a
General body repairs, exterior — 230General body repairs, interior — 279General information, paint — 133Vechile- specific paint information — 27Heating, air conditioning — 156Auxiliary heater — 58Air conditioning system with refrigerant R134a — 1297- speed dual clutch gearbox 0CW — 544- cylinder injection engine(1.4 1 direct inction. turbocharger) — 182Fuel supply system - Petrol engines — 59Running gear, axles, steering — 221Brake system — 92Wheels and Tyres guide — 12Guide for using trailers — 11Wheels and Tyres Guide - General Information — 121Brake system (hybrid) — 73Electrical system — 326Communication — 65Electrical system, general information — 111
3steps
~18min
2/5difficulty
Done 0 of 3

A- low-pressure side of the refrigerant circuit.

B- high-pressure side of the refrigerant circuit.

Refrigerant circuit with expansion valve
Component Overall state of the refrigerant Pressure (in bar) Temperature in degrees Celsius
-1- evaporator, from inlet to outlet Vapour approx. 1.2 bar → Remark approx. -7°C → Remark
(approx. 1.8 bar) → Remark approx. -1°C → Remark
-2- Air conditioning system compressor A-side Gas approx. 1.2 bar → Remark approx. -1°C
(approx. 1.8 bar) → Remark (approx. +1 °C) → Remark
-3- Air conditioning system compressor B-side Gas approx. 14 bar approx. +65 °C
-4- Condenser Gas, vapour, liquid approx. 14 bar at outlet approx. + 55 °C
-5- Receiver Liquid approx. 14 bar approx. +55 °C
-6- Extraction and charging valve, B side Liquid approx. 14 bar approx. +55 °C
-7-Expansion valve Liquid, released into vapour approx. 14 bar approx. +55 °C, reduced to -7°C
-8- Extraction and charging valve, A side Gas approx. 1.2 bar → Remark approx. -7°C → Remark
(approx. 1.8 bar) → Remark approx. -1°C → Remark
  1. The pressure in refrigerant circuits with regulating air conditioner compressor is held to approx. 2 bar despite changing heat transport and differing engine speeds. This applies however only within the rated range of the air conditioner compressor; if the rated range of the air conditioner compressor is exceeded, the pressure will increase → Chapter.
  2. The temperature in refrigerant circuits with regulating air conditioner compressor is held within the regulation range of the air conditioner compressor despite changing heat transport and differing engine speeds. This applies however only within the rated range of the air conditioner compressor; if the rated range of the air conditioner compressor is exceeded, the temperature will increase. → Chapter
  3. Measured values for air conditioning systems with two evaporators
Note Air conditioning system compressors that do not self-regulate their load are switched off by the respective control unit via the air conditioner compressor regulating valve -N280- when an evaporator temperature less than 0 °C is sensed. In vehicles with air conditioner compressor regulating valve -N280-, the pressure on the low-pressure side is varied by activating the valve.

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