Volkswagen Touran Service Manual: Pressure and Boiling Point

Volkswagen Touran Service Manual / Heating, Ventilation and Air Conditioning / A/C System, General Information / A/C Technology Basic Principles / Pressure and Boiling Point

The boiling point given in tables for a liquid is always referenced to an atmospheric pressure of 1 bar (14.5 psi). If the pressure acting on a fluid changes, its boiling point also changes.

For example, water boils at a lower temperature the lower the pressure.

The vapor pressure curves for water and refrigerant R134a show that, at constant pressure, reducing the temperature changes vapor to liquid (in the condenser) or that reducing the pressure causes the refrigerant to change from liquid to vapor (evaporator).

Vapor pressure curve of water

A -

fluid

B -

Gaseous

C -	Vapor pressure curve of water

1 -	Pressure acting on liquid in bar (psi)

2 -	Temperature in C (F)

Vapor pressure curve of refrigerant R134a

A -

Fluid

B -

Gaseous

D -	Vapor pressure curve of refrigerant R134a

1 -	Pressure acting on liquid in bar (psi)

2 -	Temperature in C (F)

Physical Principles

The four known states of water also apply to air conditioning system refrigerants. 1 - gaseous (invisible) 2&n ...

Refrigerant R134a Vapor Pressure Table

The vapor pressure table for every refrigerant is published in literature for refrigeration system engineers. This table makes it possible to determine the vapor pres ...

Other materials:

Volkswagen Touran Owners Manual. Interior and reading lights
First read and observe the introductory information and safety warnings Button / Position Function Switches off the interior lights. Switches interior lights on. Switches door contact switch on ( ...

Volkswagen Touran Owners Manual. Recycling and scrapping end-of-life vehicles
First read and observe the introductory information and safety warnings Recycling of end-of-life vehicles Volkswagen has already made provision for the time when you choose to have your vehicle recycled in an environmentally-friendly manner. A recycling system which operates in many Europea ...