Year: 1983
Make: Mercedes
Model: 240D
Engine Size: 2.4l
Refrigerant Type: Envirosafe R12
Ambient Temp: 85f
Pressure Low: -20inHG
Pressure High: 150PSI
Country of Origin: United States
I have an 83 Mercedes 240D with an AC Delco AC system which takes 2.9lbs of R12. I have put on a parallel flow condenser (original sprung a leak, thanks for that buddy). I have vacuumed it out and added the correct amount of oil (150 ml mineral oil - 50ml for each of the lines, condenser and new receiver drier).
I put in 2 cans of ES-12 (6 oz each = 36oz equiv R12. They say 6 oz is equivalent to 18 oz of R12). However, it is not coolnig and the low side is showing a vacuum -25inHG, high side is 130PSI.
That's classic low refrigerant. So I added more, nothing happened, so I added more. It has 4.5 cans of ES-12 in it now and there is still a vacuum of 10inHG Low side, high side is 150PSI. It should be 30-45 low and 250 hi. 4.5 cans of ES-12 is supposed to be equivalent to 5lbs of R12! WTF?
Any idea on why it is not working? Compressor is obviously working - big vacuum on low side. There was no leak down after vacuuming, so there is no leak. Can't be stuck TXV - there is pressure on high side, right?
Sounds like low refrigerant, but how could it be? Maybe the new condenser has a greater volume, but geez, not that much surely.
Bamfoozled....
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1983 Mercedes 240D on R12 and WVO!
1192 Mercedes 300D 2.5 R134a
1993 Toyota Pickup converted to R134a
Sounds like the valve is stuck. But who knows how well it will operate with a refrigerant thats not designed for use in cars. Plus it's illegal to use in a car. Your not going to get much help on this board with that stuff in the car.
That is not classic low charge, however it is classic expansion valve problem.. Change it, the refrigerant is pooling in the condenser, which is why the high side is not going thru the roof....Bad expansion valve..Use an automotive refrigerant like R12 or R134a when you fix it..
Depending on the "original" problem, more work may be needed, but for now, change the expansion valve..Hope this helps..
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Chick
Email: Chick
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Freedoms just another word for nothing left to lose
Chris, that's the first I've heard of ES-12 not being allowed in cars. All i've heard is you're not allowed to mix it with other refrigerants, which I haven't. And that it must be a converted R134a system, which mine is. Also, I have read a number of people who say it works well in their cars.
Webbch, thanks for the tip.
Sounds like I'll have to see if my TXV or lines are blocked.
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1983 Mercedes 240D on R12 and WVO!
1192 Mercedes 300D 2.5 R134a
1993 Toyota Pickup converted to R134a
Thanks Chick.
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1983 Mercedes 240D on R12 and WVO!
1192 Mercedes 300D 2.5 R134a
1993 Toyota Pickup converted to R134a
Thought we were going to avoid HC refrigerant discussions on this board. Doesn't EnvonSafe have a board of their own? They use to with all kinds of "good" advice like adding air to the system and not really worrying about leaks where the butane blows out first so the propane can blow up your system.
People with a Mercedes of this era never did get good cooling, even with R-12, those that did, converted to R-134a with a parallel flow condenser and increased condenser cooling. Would be good to also change the evaporator and venting system as well, but a way too much work, so you have to live with it or move to Wisconsin.
Ha, rode with an associate with a brand new Mercedes of that era in Las Vegas in the middle of summer and thought I was going to die, he wouldn't let me roll down my window, and dying was only a small price to pay for having the prestige of driving a Mercedes. Next time, said no thanks, took a cab.
We have had 3 posts in the past two weeks where an HC refrigerant was used with poor performance. If this was R134a people would be claiming the refrigerant was the issue! Last time I looked none of the HC sites had a forum like this Nick. Just a few with the typical HC promotional data. Yes there are loop holes so some can use an HC refrigerant. But they are loop holes to use something many would never use!! Also last time I looked the stuff it was not that cheap to begin with. Anyone using it places themselves at the risk of never having their vehicle looked at by a professional shop in the future.
But there is one way to fix this issue as I have read about it on the Internet. Install a VOV valve, after all I've seen one guy claiming to have sold trillions. Add some Magic32, RET2000000000 and one or more of the super sealers. Yes I think that should repair any a/c issue for years to come. Maybe get some of that refrigerant that claims to clean the inside of your system also. One thing that has me questioning that stuff though. If it cleans you system and you never open it again. Where does the stuff that was cleaned go?
My favorite HC video!
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How far back does my memory have to go? But it was in the old board before ACKits in the alternate refrigerant section, lots of EV people were there.
Also thought the only way to buy EV today was to find a guy wearing a large overcoat in the middle of summer on a street corner, where he swings it open to expose cans and cans of EV.
Your memory is pretty good recalling the miracles of the VOV, forgot about that. And I would never use an additive unless it has the words, frigid, ice, arctic, or really cold on it. And since I am a tree hugger, must have some form of environment in it. Somehow, Death Valley or Sahara Hot doesn't go well with me. Really don't like the sound of R-12 or R-134a, just too proletarian.
TXV is indeed stuck closed - either that or there's moisture in the system and it's icing up at the TXV. Remotely possible would be low side restriction. Check for icing around the TXV when it goes into vacuum.
If you want to check the TXV, look up some of my old posts on how to do it.
Either way, you need to replace the TXV and receiver dryer, and charge to spec with R-12.
Envirosafe, LOL... I knew that was green agenda all along, save the environment and kill people. It's only a matter of time before we go back to early refrigerants, like R-717 (ammonia), or even better yet R-764 (sulfur dioxide) or R-40 (methyl chloride), this way when there's a leak you end-up dead... just like in the ole' days. This is why CFC based refrigerants were invented.
The green movement is all about death, death to industry, death to the economy, death to people (notice how they all support abortion).
I figure what the heck with the rant... this is an environsafe post anyway.
Joe
Last time when the system was non-functional the desiccant probably came apart like fine brown powder and is now blocking the TXV. If that is yoru case, treat it like a compressor failure. Make sure you flush the evaporator and if your compressor inlet has a screen make sure that is clear as well.
Like the others said... stay away from HC. If your compressor is relatively new then it should handle R134a. If it's older just make sure it has Neoprene seals, not Viton ones. Flush out the mineral oil and throw in DEC-PAG and go with R134a.
I know I am new here, and have no standing to complain, so let me invoke old guy's priveledge. I have been away from AC for decades. And what I was involved with way back when seemed pretty sophisticated to me at the time. In perfect hindsight, it was the minimum of the minumalist. Now, times have changed, and I want to dable a bit. So I searched the net, and here I landed. It did not take me very long to see that this site was clearly head and shoulders above the others. There are very few technical forums as good. But, I have to say that some of the resident experts here should lighten up just a little. Perhaps you could put yourself in a non experts place for a bit. After all, that is what you are here for, isn't it? To educate and help those willing to give it a try? I have seen the ads for the various alternative refridgerants, and they look real convincing. REAL convincing. Are you really surprised that folks would get duped into using them? Then search for help when failure arises? I think it is pretty unreasonable to bash someone who comes here seeking help that has used an alternative refridgerant. How could they know. If I had not read it here, I would probably have become a victim too. You do folks a service by letting them know that the alternatives are bad news, and why. But you do yourself a diservice by bashing them for it. Ok, my old guy's priveledge has expired. rant over.
Yep, but the loop hole Chris is the r12 system has been converted to R134a. So the HC proponents say this allows them to now use an HC. This is mentioned on the EPA site as a shame retrofit or conversion. Basically in my opinion the EPA when creating these laws. Never thought someone would take a R134a designed system and start adding other refrigerants. So there is this loophole some try and exploit.
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Not trying to beat a dead horse here either, but this year it seems that the techs here have not even bothered to bring up "compressor" warrany when using alternatives. Most companies are denying claims now for any damage when alternative refrigerants are used..I guess thats another thing we've grown tired of pointing out..That and inproper flushing where residual flush is degrading the oil leading to premature compressor damage.. "The times they are a changing"...
Not to mention all the ebay sales of compressor on a board "sponsored" by a company who sells ac parts, and stands behind them..Kinda a slap in the face don't you think?? Yet he (Tim) doesn't complain..
oK, iI've had my rant now...time to go to bed...
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Chick
Email: Chick
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Freedoms just another word for nothing left to lose
Many of the Hydrocarbon refrigerant manufacturers are located in Canada. There is no restriction on the use of hydrocarbons in automotive systems in Canada (or anywhere else outside the U.S.) and it's use is considered to be in the spirit of the UN Montreal Protocol. The suppliers openly claim the hydrocarbons are drop-in replacements for R12 (except in the U.S.) and R134a.
I don't know how this is working out but if you service a Canadian car, be careful.
In the U.S. there is no Federal restriction on the use of hydrocarbons to replace R134a. Only 18 States (and the District of Columbia) ban flammable automotive refrigerants so they may show up anywhere. The largest hazard this presents is to technicians servicing the system, especially if the system content is unknown.
The OP later stated that the system was previously converted to R134a. The conversion to a hydrocarbon refrigerant may or may not be legal depending upon in which state he/she lives.
I know that the flammable refrigerants are legal where I live, but so is assisted suicide.
Edited: Sun July 27, 2008 at 1:08 AM by retrofit
It is exasperating to give out good information to the know it alls, only to be told you are wrong, and that they and their alternative product is right. In the face of that, an invitation to go elsewhere is certainly warranted.
Nobody bashed me, and in fact, I do not remember anybody bashing any individual. I only recall the tenor of some answers treating some questions as if they were stupid questions, and that the poster should go elsewhere. There are truly no stupid questions. Questions that may seem that way are only a reflection of the state of mind of the asker. Along with that state of mind is a quest to get it right. What needs to be guarded against is stupid answers. The world has no shortage of those.
Every forum has its irritant. It does not take long to figure out that alternative refrigerants are the irritant here.
From my subjective view, the tone on this thread is not entirely friendly in parts. I didn't feel the sense of community that I do at other forums.
I understand some of the experienced guys are tired of 'stupid' questions.
To the guys who addressed my AC issue and have pointed me to the TXV, thanks, I appreciate it. I've got a new one and will be cleaning out the system....after my brother in law gets married today and my hangover wears off tomorrow....
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1983 Mercedes 240D on R12 and WVO!
1192 Mercedes 300D 2.5 R134a
1993 Toyota Pickup converted to R134a
I'm not trying to be contentious here, I'm just trying to get to the bottom of this. I want to know what the issue/s with the iso-butane/butane refrigerants is.
Is it the legal issues?
Is the safety issues?
Is it performance issues?
I'm talking specifically about the iso-butane (R600a) type refrigerants like enviro-safe ES-12, not the other stuff like Freeze12s etc.
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1983 Mercedes 240D on R12 and WVO!
1192 Mercedes 300D 2.5 R134a
1993 Toyota Pickup converted to R134a
Do a little research before calling out our members. Both these links were in the tips forum. The OP listed they are a US resident. These rules apply to his conversion!
http://www.autoacforum.com/MACS/HCwarning.pdf
http://www.epa.gov/Ozone/snap/refrigerants/hc12alng.html#q5
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