Volkswagen Polo Service & Repair Manual: Critical Point
| Vehicle air conditioning systems make use of the
vaporization and condensation process. In this case, one works
with a substance which boils easily, designated as refrigerant. |
| The refrigerant employed is tetrafluoroethane R134a, which
boils at -26.5 °C (-15.7 °F) at a vapor pressure of 1 bar (14.5
psi). |
| The critical point (critical temperature and critical
pressure) is that above which there is no longer a boundary
between liquid and gas. |
| A substance above its critical point is always in the
gaseous state. |
| At temperatures below the critical point, all types of
refrigerant in pressure vessels exhibit both a liquid and a gas
phase, i.e. there is a layer of gas above the liquid. |
| As long as there is still gas present in the container next
to the fluid, pressure is dependent on ambient temperature.
Refer to
→ Chapter „Refrigerant R134a Vapor Pressure Table“. |
 Note
| Different types of refrigerant are never to be mixed. Only
the refrigerant designated for the corresponding A/C system may
be used. |
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Vehicle air conditioning systems make use of the
vaporization and condensation process. In this case, one works
with a substance which boils easily, designated as ref ...
Vehicle air conditioning systems make use of the
vaporization and condensation process. In this case, one works
with a substance which boils easily, designated as ref ...
Other materials:
Lower section of the centre console
Fig. 8 Overview of the lower section of
the centre console
Key for :
Lever for:
Manual gearbox
Automatic gearbox
Stowage compartment in the front centre
console
12-volt socket
Drink holder
Handbrake
Stowage compartment in the centre
armrest
...
Infrared Dryer -VAS6873
Definition:
Infrared Dryer -VAS6873-
Product Description:
The short-wave infrared dryer is used to quickly dry paste,
filler, base paint, top coats and clear coats for minor repairs.
...
Service and disposal of belt tensioners
First read and observe the introductory information
and safety warnings
Seat belts may become damaged during any work on the belt tensioners or while
removing or refitting any vehicle parts in conjunction with any other repair work.
This damage will not always be noticeable. The consequence m ...
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Refrigerant R134a Physical Data
Refrigerant R134a Environmental Information