Automotive Air Conditioning Information Forum

Hey everyone, first topic here

TLDR: check the pictures below, on this evaporator style, does the refrigerant passes through the lines in green (like a serpent route on the fins) or does it pass just on the two main large tubes on the top (in blue) ?

I am messing with my 99 GM Vectra AC since it never worked properly... added gas two times and leaked, first replaced an HP hose, now its the compressor seal, I fixed it all and decided to take de evaporator out to check too, but in order to remove you need to remove the dash... a hack people use is to just cut /drill the side cover (on AC box) and later glue a new one, this helps a lot since this dash is old plastic and lots of things to break plus the time.. well, I accidently got some marks on the evaporator when drilling this out.. wondering now if this really affects it or not... I didn't see any route on the bottom to connect as the green route so I imagine its passing just on the top? does anyone knows? thanks in advance!

That's a 3-pass PF evap; there are other types. In this case, the refrigerant flows in sections, as shown in the green flow pattern. You can see each section from the weld marks close to the fitting connection. See your 3rd image.

thank you, I guess I am thinking too much out of this... looking at the bottom there is no connection/bridge between the fins.. all I see is two big tubes in the top and small passages that ends like a "T"... not really sure how it circulates if just ends there.. would be cool to have a cut image to understand