Refrigerant R134A: Notes
WARNING: This page is about a different car, the 2023 Audi S3, 2023 Audi RS 3, 2023 Audi A3 Quattro, and 2023 Audi A3. However, it is still accessible from the selected car via links, so may be relevant.
A/C systems in vehicles utilize the vaporization and condensation process. Thus one must work with a substance that boils easily, which is described here as refrigerant.
The refrigerant used is tetrafluoroethane R134a, which boils at -26.5 °C (-15.7 °F) at a vapor pressure of "1 bar (14.5 psi)" (absolute pressure corresponds approximately to the ambient pressure).