98 S70 T5 What happens to refrigerant in AC system?

[SpeedyPete]

Hello all Can anyone please tell me how refrigerant can escape a sealed AC system with no leaks? I took the car in to have the AC serviced. It was die/pressure tested and just needed some refrigerant added. So were or what is going on here with the refrigerant? Thanks in advance, SpeedyPete

[cn90]

Think about tire...even with perfect tire, perfect installation, air still escapes through the "pores" in the rubber compound. Inflate the tire and let it sit in the garage, a year later, you will lose most of the air!

The R134a does leak out of even a brand-new car from the show room. It leaks through the front seal, O-rings etc. in minute amount.

The website below shows you the so-called "normal R134a loss", which is acceptable:
http://www.oekorecherche.de/english/bei ... -loss.html

There was a paper published by SAE (Society of Automotive Engineers), I will try to find it when I have time.

In the mean time, this is a good paper to read:
http://www.umweltbundesamt.de/sites/def ... g/3110.pdf

[polskamafia mjl]

+1

No AC system is perfectly sealed.

[abscate]

You won't see dye come out of one of the most common AC problem spots on old cars, the AC evaporator. It's buried deeply under the dash.

My evap replacement came up this spring with the same nice cold temp differential from last year with no added Refrigerant!

Bravo Zulu