B9Meh

Hello all had to replace an ac line in my 2018 S5 Sportback and long story short got the adapters for the r1234yf refrigerant to fill Freon back up and was wondering if our systems are anyway compatible with the old r134a? I know Mercedes had a whole thing with recalling the new Freon and just filling their cars back up with the old stuff to be able to be sold again. Can someone chime in on this and let me know if I’m completely misinformed lol. Thanks!

SloopJohnB@mac.com

Still, the answer is an emphatic, “No.” Not only would a retrofit of this type negate the environmental benefits of R-1234yf, but it would also be a violation of Federal Law under Section 203 of the Clean Air Act: “tampering” with a vehicle's emissions control device.

Theoretically the R1234yf nipples won't allow a 134A female adapter...you'd have to use the R1234yf female quick connects on hose to a manifold and then load the manifold from a can of R134A. There are also issues with the oil used in the R1234yf system that may not play nice with R134a.

For reference, MB DID a recall of some 400 vehicles in 2012 to replace the flammable R1234yf with R134a due to fire hazard in collision but it was a specific exception. I suspect it could be done with your system, but it would involve evacuation, replacing dryer/filter/if not expansion device, as well as draining/flushing/refilling the compressor with oil compatible with R134A and replacing the nipples/hoses that use an R1234yf nipple with nipples/hoses compatible with R134A fittings. And it would be a violation of the Clean Air Act.

https://static.nhtsa.gov/odi/rcl/201...2V478-9042.pdf

B9Meh

I appreciate your quick response looks like I’ll source the 1234yf from somewhere lol thanks!

MattCarp

So. It appears Audi doesn't use a "standard" R-1234yf fitting on the service ports. Does anyone know the appropriate connector into the low side port? I need a shot of refrigerant (I know, I need to look for leaks and fix them...)

2018 S4

MattCarp

...I could be wrong about the fitting. I just may not have the right one!

SloopJohnB@mac.com

Worst case you buy a low side R-1234yf coupler (google R-1234yf coupler), the set is less than 20$. Of course that assumes you have hoses/manifold/gauge for AC refrigerant work. You could also buy this and get a can of R1234yf.
:

SloopJohnB@mac.com

SloopJohnB@mac.com

I just love saying that. Sorry, not sorry.

MattCarp

Not so easy, Johnny B. I bought this:


but, the r1234yf isn’t deep enough. I like the gauge, hose, and the can tap, so I’m keeping it. I decided to try again on the port connection with this:


I’ll find out…tomorrow!

MattCarp

Okay - the Audi suction side quick connect port is DEFINITELY NOT STANDARD.

Does anyone know what adapter / fitting to get?