Volkswagen Golf Quiz
Air conditioning system with refrigerant R134a

Vapour pressure table for refrigerant R134a

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
~1min read

The vapour pressure table for each refrigerant is published in the literature for refrigeration engineers. This table shows the vapour pressure exerted on the liquid column in the container for a given temperature of the container. Since a characteristic vapour pressure table is known for every refrigerant, one can determine what refrigerant is present by measuring pressure and temperature. Note Absolute pressure means that 0 bar corresponds to an absolute vacuum. The normal ambient pressure (positive pressure) corresponds to 1 bar absolute pressure. On most pressure gauges, a reading of 0 bar corresponds to an absolute pressure of one bar (which is confirmed by the existence of a -1 bar marking beneath the 0 scale marking).
Temperature in °C Pressure in bar (positive pressure) R134a
-45 -0.61
-40 -0.49
-35 -0.34
-30 -0.16
-25 0.06
-20 0.32
-15 0.63
-10 1.00
-5 1.43
0 1.92
5 2.49
10 3.13
15 3.90
20 4.70
25 5.63
30 6.70
35 7.83
40 9.10
45 10.54
50 12.11
55 13.83
60 15.72
65 17.79
70 20.05
75 22.52
80 25.21
85 28.14
90 31.34

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