Volkswagen Golf Quiz
Air conditioning system with refrigerant R134a

Pressure and boiling point

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 boiling points given in the table below are always based on an atmospheric pressure of 1 bar. If the pressure on a liquid is changed, its boiling point changes also. It is well known that, for example, the lower the pressure, the lower the temperature at which water boils. The vapour pressure curves for water and for refrigerant R134a show that at constant pressure and falling temperature the vapour becomes liquid (in the condenser), and that when pressure drops, the refrigerant changes from liquid into the vapour state (evaporator).

Vapour pressure curve for water

A - Liquid
B - Gaseous
C - Vapour pressure curve for water
1 - Pressure on the liquid in bar (absolute)
2 - Temperature in °C
Pressure and boiling point

Vapour pressure curve for refrigerant R134a

A - Liquid
B - Gaseous
D - Vapour pressure curve for refrigerant R134a
1 - Pressure on the liquid in bar (absolute)
2 - Temperature in °C
Pressure and boiling point

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