$0 R-134a recovery.

[oil pan 4]

Problem is don't have a recovery tank I can feed into. I have a gauge manifold. The disposable tanks I have have built in check valves so you can't pump into them.
My recovery bottle that I can pump into has R-290 in it.
So this is my solution. From a more elegant time.

Only problem is I've only got a single kinda empty 12 ounce can with maybe 2oz in it, this car holds more like 24oz and my truck is probably already over charged slightly. Usually if I need to do R-134a recovery I just shoot it into another vehicle with my manifold gauge.
I took my nearly empty can of R-134a and stuck it in the freezer last night. Stuck the service head on the can, put a bunch of ice in the bottom my wife's larges tumbler, then crushed ice on the sides. I still wasn't sure if this little cheapy service gun had a built in checkvalve. I hooked it up squeezed the trigger and could hear vapor hissing into the can and the exposed part of the can went from freezing to warm in about 2 seconds, as it's already 90f out this mornin so it should work. Tided the trigger back with a sock.

 

[JavierH19]

I've heard of this but have never tried it.

 

[oil pan 4]

I'm going to check the trash cans at the local auto parts stores for empty 134a cans later today it's supposed to be over 100f with low thunderstorm chances.
After 2 hours most of the ice is melted and the can feels full.
If I can find an empty can I'll weigh it before and after.
It's definitely working.

 

[oil pan 4]

Yep a normal can of supertech 12oz r-134a weighs about 437g.
The one I filled weights 511gm lol. I'll keep it in the fridge till it's time to use. It absolutely feels more full than any of the news cans I have.
If I had to I could shooting a few ounces into the already full can but I'd rather not.

 

[oil pan 4]

I did $0 recovery yesterday for maybe 2 hours and pulled out 10 to 12 ounces.
I put a can with no liquid only pressure on there today, weighs 100gm.
Put the service gun into the ice bath and tied back the trigger.
Today it's 102f out, the cars A/C system has almost 150psi so there's still probably liquid 134a in there.
Ran the setup for 30 minutes, collected several ounces, melted most of my ice, added more ice and I'm going to check it again after it's been an hour total.
I figured this was going to be a lot slower than it is. When I ran it yesterday I left it alone for an hour, came back and all my ice was melted and the can was significantly fuller, added more ice and came back another hour later and I could tell it was over full.
So this process happens pretty quick when it's 100f out so long as I keep the recovery bottle in ice.

 

[oil pan 4]

After an hour and 20 minutes system pressure is down to 45psi.
Pulled another 7oz out.

 

[oil pan 4]

All the R-134a I pulled out with the $0 method went back in plus 2 to 4 ounces of new stuff to make up for the 30psi that was left in the system.
The cars A/C appears to be as good as new.

 

[nthach]

I’ve heard of using an evacuated can or an old propane tank, and having it in a bath of dry ice and alcohol(IPA or EtOH) with success. It’s disposing of that refrigerant if contaminated that is an issue.

 

[oil pan 4]

I’ve heard of using an evacuated can or an old propane tank, and having it in a bath of dry ice and alcohol(IPA or EtOH) with success. It’s disposing of that refrigerant if contaminated that is an issue.

Dry ice and alcohol costs money.
It would work pretty good with cooler ambiant temps.
On cooler days using regular ice like I did would barely work.
Depends how contaminated it is, what it's contaminated with. If it's not from a burned up electrical compressor you could always run it and see if it blows up.

 

[brages]

You could toss in some rock salt to get the ice a little colder

 

[CarlB]

I too know of a $0 method to empty a system.

 

[oil pan 4]

I too know of a $0 method to empty a system.

And charge it back up when finished?

 

[CarlB]

And charge it back up when finished?

I don't reuse refrigerant.

 

[oil pan 4]

I don't reuse refrigerant.

Why it's good practically forever, till it gets fried inside of an electric compressor, then it needs a purification machine which is big bucks.

 

[chorty]

It's safe for the dirt. How many vehicles have gotten into accident's and dumped this **** all over the road?

please. Don't even.....No.

 

[oil pan 4]

It's safe for the dirt. How many vehicles have gotten into accident's and dumped this **** all over the road?

please. Don't even.....No.

Refrigerant is a gas at atmospheric pressure.

 

[chorty]

Not the oils. Granted it boils out of the oil.

 

[oil pan 4]

Not the oils. Granted it boils out of the oil.

Yeah I'm sure ester oil would break down in the environment very quickly compared to pao or even dino oil.

 

[chorty]

Dont remember what was used in some of our cascade systems.

R404 on first stage.

Then used 404 to pull heat off r23.