Evidence Of Leaks
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2018 Audi S6, 2018 Audi A6 Quattro, 2018 Audi A6, 2017 Audi S6, and 2017 Audi A6 Quattro. However, it is still accessible from the selected car via links, so may be relevant.
External damage, for example, can cause a leak in the refrigerant circuit. The small quantity of refrigerant escaping from minor leaks can be detected, for example, by using an electronic leak detector or by introducing a UV-leak detection additive into the refrigerant circuit. Electronic leak detectors are capable of registering leaks with refrigerant losses of less than 5g per year.
NOTE:
Use leak detectors designed for the type of refrigerant. For example, a leak detector for R12 refrigerant will not work with R134a because R134a refrigerant has no chlorine atoms so the leak detector will not respond to it.