Bubbles in AC Sight Glass
 

My car is a '95 E300 series and came with Freon-134.

The ambient temperature here (Montreal Canada) is now around 32F. I happen to look at the Air Conditioning sight glass while the AC compressor was running and noticed lots of bubbles.

Does that mean that I may be low on Freon, or are the bubbles due to the low ambient temperatures?

Thanks

Phil

It might mean it is too cold for AC.

Phil's right...

Said another way. It's easiest to check a/c charge on the *hotest* day of the year! If you get a 30 C day, the system has more pressure differential.


Michael

I tried a little experiment in my garage by pointing a hair dryer at the evaporator.

After a few minutes I noticed that the Freon started to rise in the sight glass. This leads me to believe that once the hot weather returns those air bubbles will disappear.

Phil