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:
Protecting
Caution
Missing protection leads to the electrical system
damage.
Note
All threaded connections must be tightened to the specified
torque.
...
White Polishing Cloth -VAS6176
Definition:
White Polishing Cloth -VAS6176-
Product Description:
Extremely soft cloth for sensitive, exacting polishing. A
combination of rayon and polyester fibers make it especially
fluffy. ...
Battery Test, Performing using Battery Tester -VAS6161
Special tools and workshop equipment
required
Battery Tester -VAS6161-
WARNING
Risk of injury. Follow all Warnings and Safety
Precautions. Refer to
→& ...
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