Unsuccessful attempt to recharge A/C - Page 2 - PeachParts Mercedes-Benz Forum

Carrameow · #16 05-26-2007, 02:01 AM

Quote:

Originally Posted by rbardolv

....and that would explain why, when I tried putting in some oil charge to my system my can tap gauge showed 115lbs from the can and was going no where else.... Its those damn valves not even touching and / or doing anything... Yeah that was a waste of a good can of oil charge. Got all over the damn place too!

I guess Ill go fiddle with those valves and make them work properly.

feel good I helped some1

cewyattjr · #17 05-26-2007, 10:02 AM

Quote:

Originally Posted by Knightrider966

Your using the wrong AC fill system! Those all in one trigger unit's are junk. I've never gotten one to work yet, but they leak like a sieve. As far as your AC pump is concerned, you will not get the pump to come on unless you get some pressure into the system first. Your can of Refrigerant will turn cold when it is being inducted into the system properly. However, too much oil in your system will reduce it's effectiveness for cooling. This could be your problem since refrigerant leaks are usually gaseous and not liquid and refrigerant oil will remain oil even at atmospheric temps.

That definitely did the trick! Thank you! Just got back from Autozone and put in two cans and things are cooling nicely now.

In the area of "second thoughts" -- the previous owner assured me that the R12 was evacuated. In case there is still oil from R12 in the system, what's the worst that could happen if you add the R134a? Lose the compressor over time, or is it potentially more volatile than that?

Thanks again for the advice, the simpler hose 'n tap worked perfectly, can got cold just as described and sucked right in there.

-Chuck

Matt L · #18 05-26-2007, 10:14 AM

The R12 mineral oil is not miscible in R134a, so it won't travel with the refrigerant. This causes it to get stuck in low spots; some of these spots are intended to hold liquid refrigerant (such as in the receiver) and some of them are intended to hold gas and liquid oil (such as in the evaporator or compressor). This isn't a good thing, but may never come back to haunt you. Or it might.

Knightrider966 · #19 05-26-2007, 01:10 PM

Quote:

Originally Posted by cewyattjr

That definitely did the trick! Thank you! Just got back from Autozone and put in two cans and things are cooling nicely now.

In the area of "second thoughts" -- the previous owner assured me that the R12 was evacuated. In case there is still oil from R12 in the system, what's the worst that could happen if you add the R134a? Lose the compressor over time, or is it potentially more volatile than that?

Thanks again for the advice, the simpler hose 'n tap worked perfectly, can got cold just as described and sucked right in there.

-Chuck

Great! glad I could help you! I remember the HUMID dog days of summer in New England. Air Conditioning was more of a moisture removal aid than actually cooling but even that makes a BIG difference. Carrameow, Interdynamics is made in China now and I would not recommend those if anything else is available! I got my set of manifold gauges from Napa and those are made by Stewart Warner! Now I know those are more expensive, but not that much more and they are worth it. you are not going to get the small 14 oz. cans of refrigerant to fit on the suction hose though. you will have to make your own adapter to get that to work, but everything you could need is available at any ACE hardware store and would do the trick. Not All of you guys will need the manifold gauges, but get good ones if you do! A good set will not be hard to recognise. I would go to NAPA, get AMERICAN made parts and make sure you are buying solid brass at the strees points where it matters, like the coupling connectors. Remember, when you retrofit to R134, your sight glass is useless when your close to the fill point. R134 works best when the system fills with about 10% less refrigerant than R12! R12 is going the way of the dinosaur, it is no longer being made and when it's gone it's gone. If your system is not working well on r134, which I hear a lot, it's because the system is NOT put on a vacuum pump for a complete purge and flushed properly! My dash vents are producing temps at 49* when it's 103* in the shade! At the least to properly fill your system, use compressed air to evacuate your condensor and evaperator of old refrigerant oil and you will notice a difference. In Phoenix, the air here is very dry and results will differ with climate changes and humidity. Good Luck and don't cook (in your car that is!) Have a great Memorial day and don't forget to thank a Veteran for your freedom! Many have paid the ultimate sacrifice, with their lives and we own them a debt of gratitude!