Recovering Refrigerant

[Glacier991]

I often tell folks to have their refrigerant recovered. I realize no one has the machinery to do that DIY, but I might help by showing how it works. I redid a VW bus system (See thread "Recharging your AC A-Z") and now it stopped working. My best diagnosis is a stuck expansion valve. To fix it I needed to recover the charge. I decided to take pics. Here is the set up.... recovery machine hooked to manifold gauge set:

Here's the back side and recovery cylinder

The business happens here once you are all hooked up..

After about 5 minutes the gauges ... falling as we go... show this...

a little later..

and soon the entire charge is gone....

The machine keeps running until the reading is 9 inches of vacuum, when it shuts off.. then I let out the recovered oil..... here is the oil..

This much oil will go back in. So now I disconnect everything.... and I have a system ready to work on... and saved the refrigerant for reuse. THere is newer and better equipment, but in general it all works the same.

I offer this in hopes to explain how it is done. And why you should expect to pay for it. If it is clean they should be willing to replace it for a small fee, less than the refrigerant cost.

 

[V8BoatBuilder]

Very informative! Thanks!

Is the recovered refrigerant filtered and ready to be re-installed directly from the jug? Or is it "dirty?"

In the "usefull threads" forum, links to all of the A/C threads should be inside one thread.

 

[Glacier991]

The other side of the machine is the side that recirculates the oil through a filter and dessicant... you have to have about half a jug before that side will work.... but you in essence "purify" the refrigerant for reuse. I'll show some pics of that when I get back home.

 

[MONMIX]

I dunno about you but I put a good bit of vacumn on the system and close the hand valves. Let it sit for ten or fifteen mineuts. Come back and look at it. If the needle has not moved I know it is solid if the needle drops, I need to hunt down the leak.

 

[Glacier991]

I always do that for leak detection.... but in truth think about it... if the system is vacuum, the leak is looking for a 14.7 lbs per inch (atmosphere presssure) leak. Operating System leak will be 30 to 250 psi... so the sniffer is a far better leak checker... but I ALWAYS do exactly what you said MONMIX. And fins my share RIGHT THERE.

 

[MONMIX]

Well, for me this is 90% of the time post collission, and not service. So we are talking two different approaches.
What I am saying is, I will put in a new condenser, or a pipe or somthing that had been destroyed. I do the vaccumn to check my work and make sure all the connections are solid. If there is a leak out side of the collision area, it is not our issue. ( ya gotta love insurance work )

 

[mechanic021]

hey monmix i sent you a pm asking you a body question did you recieve it?