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:
Coolant specification
First read and observe the introductory information
and safety warningsThe cooling system is filled at the factory with a mixture
of specially prepared water and at least 40% coolant additive G 13
(TL-VW 774 J). The coolant additive is dyed purple. This mixture of water and coolant
additive ...
Tire Service Life, Influences
The following factors influence the service life of a tire
in varying degrees.
Driving style:
Speed
Brakes
Acceleration
Cornering
...
Dust Cloth -VAS6177
Definition:
Dust Cloth -VAS6177-
Product Description:
Dust cloth with extremely effective light adhesive formula
for critical cleaning tasks. Unlike traditional dust cloths,
this cloth does n ...
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Refrigerant R134a Physical Data
Refrigerant R134a Environmental Information