OK I have been looking in the archives but have not seen info on what seems to be a major item in working on AC systems - namely the need for a recovery system.

I figure to work on AC on my cars I would need;

• 609 cert
• A good set of manifold gages/hoses (would need seperate sets for R12 and R134a if I plan to work on both)
• Vacuum pump

This is where all the posts seem to stop

• Recovery system - (can one system be used for both R12 and 134a with different recovery tanks?)
• Recovery tank
• accurate scale

Everything I have read refers to the vacuum pump and gages. I did not find any info on recovery. It seems to me that if I have to bring the car somewhere to empty the system it may not be worth it to do everything else?

A check of ebay lists some recovery systems that seem to go for roughly $250-350 and a recovery tank for about $70.

So how do people work on AC without a recovery system?
Vacuum pump and gages I figure would run about $300-350 add another 100 to have a manifold/gages/hoses for both 134 and r12

The recovery system would double that investment? And can the same recovery system be used for different refrigerants? The recovery system web sites list most refrigerants.

I still may be better off considering I've been charges about $120 to run a check on the 400E the last two years (recover refrigerant, pull vacuum and put correct amount of refrig. back in). If I do all 3 cars this year I'm probably in for at least $400. If I buy all the tools and refrig, I'm in for somewhere around $1k (assuming somwhere around 350 for R12 tank) but every time I need to do something in the future its "free".

Cars I would be servicing
1984 300SD (R12 never converted that I know of)
1992 400E (R134a original but has needed topping up last two years)
1986 944T (R12 original needs to be charged)
2002 320E (needs nothing currently)

Thanks
Paul Moruzzi

OK - did some more searching and found a bit on recovery.

Question is with a recovery system do I still need the vacuum pump? Most info states they have a compressor but nothing about vacuum.

Like this one
http://www.inficonrefrigerantrecovery.com/en/vortexrefrigerantrecovery.html
or this one
http://www.yellowjacket.com/prdetail.cfm?PrimCatID=110&Auto=1#a3012
ebay has some such as
http://cgi.ebay.com/STINGER2000-REFRIGERANT-RECOVERY-UNIT-NO-RESERVE_W0QQitemZ180095301269QQcategoryZ109488QQrdZ1QQcmdZViewItem
and per one thread on govt. auctions
http://cgi.govliquidation.com/auction/view?id=1149264&convertTo=USD

I'm located in MA
Thanks

I'm not sure those small portable units are capable of evacuation, I've never used one. There are lots of old R12 automotive recovery machines on e-bay - all of these machines have internal vacuum pumps. The prices of the R12 machines are very low since there is limited demand for R12 A/C services these days.

I purchased a SUN MRC300 on e-bay a couple of years ago for $125. This is a basic R12 recovery/recharge machine but it came with it's own tank and vacuum pump. The only downside to my approach is that it took me awhile to find somebody that had one for sale locally and the machine takes up a measurable amount of garage space for something that might not be used very often.

I think the small recovery units are capable of being used with different refrigerants (if you have a separate recovery tank for each unique refrigerant) but as I recall you have to go through a procedure to remove the refrigerant oils from the machine before you change refrigerants. PAG oils used in R134 and not compatible with mineral oils used in R12 systems and cross-contamination is not a good thing.

Like an empty propane tank? vacuum pump made from an old freezer compressor?Its at your fingertips!

Just curious. Why do you do that?

__________________
2012 E350
2006 Callaway SC560

If you are asking why the 400E gets checked. Its because there is a leak, AC will work for a few months. When I have brought it in they have said it holds vacuum but obviously there is a leak.

From what I know about W124's its likly to be berried in the dash. I am not going to have an AC place take the dash apart to fix it $$$. So unless I start working on AC systems myself its get it topped off yearly.

Just-n-time
Can you be a bit more specific (or state where to get specific info on converting an old compressor). Obviously the propane tank wold be used for recovery. However how do you rig everything up for proper recovery????

Paul

When you pull the compressor out of a freezer,the older units have charge ports like your car, To service the refrigerant.All you need to do is hook your gauges and plug it up,you can get around 18pounds.you will have to tinker with the tank to rig up a line to fit the hose to the tank,lost all my photo's to show how to build it,when I moved to our new home.most all of that stuff is packed away in the old barn.But if you sit and look at what you need you will figure it out.JNT