there are two reasons for pulling the system into a vaccume, the first one is to remove all oxygen and create a vaccume. the second is to remove contaminants and Water. If you simply pulled it into a vaccume and it held, thats not good enough you must keep a constant vaccume on it for atleast an hour to draw out the moisture. You must recharge the system while the system is in a vaccume state and replace the drier every time you crack the system open. Now you are in danger of damaging the ac compressor. (and these r4 radials do love to seize..)

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Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.

No! You must NOT recharge the system when charging with ES 12! You will overcharge it if you do! I know how this sounds, but after holding a vacuum for 20 minutes, shut off your vacuum pump and let the pressures equalise. The little bit of moisture you let into your system will be a lot less damaging than an overcharge.

The low side at 100*F should not be over 50 PSI! Anything over that and you run the risk of damaging your compressor! The temerature/pressure chart for R134A is close enough to ES-12A to use satisfactorily.

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"Extremism in the defense of liberty is no vice and moderation in the pursuit of justice is no virtue!"

The Greatest Arizona Senator ever, Barry M Goldwater. I hope you can see from heaven how much you are missed.

a2t

People that work on automotive HVAC systems should make sure their
primary source of information is not an Internet website where people of unknown knowledge levels offer 'information'.

There are lots of good HVAC textbooks out there - I'd really recommend you get one and study it before you try to repair your system.

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98 Dodge-Cummins pickup (137K)
13 GLK250 (157k)
06 E320CDI (341K)
16 C300 (89K)
82 300GD Gelaendewagen (54K)

It is hard to imagine that you actually want air in the system when using hydrocarbon refrigerants. Air reduces cooling capacity. Yet the vendors of hydrocarbons actually tell you to let air into the system. This seems bizarre.

Why can't you meter the hydrocarbons to avoid overcharging, even if you charge into a vacuum? It's not like you're forced to add an extra can. The amount of hydrocarbons required fill the system with gas will be minimal.

I read of one person who installed ES12 and decided to break the vacuum with propane. This would seem to throw the mix off. Why not just break the vacuum with ES12 and add what only is required?

Can someone who has knowledge of these systems attempt to break what seems to be a conundrum?

Im only going by directions given from ES12A vendor, not to charge under vac. I pulled 30 in HG, let it sit for about 1 hr, it held pretty close to 30 in HG.

Then shut off pump and let system equalize back to 0, then charged with engine running from the low side. Took the compressor a min to come on but it did, and the 2 cans of ES-12A went in.

When you guys say system pressure should not exceed 50 psi on low side, is that idling? Mine will reach about 60 sometimes before the fans kick on and it lowers. If I give it some rpms, say 2500, the low side pressure drops to about 20 psi (dont know if thats normal).

I, too, think the issue is probably too much oil. Why else would the site glass be milky? When I pulled the vac, site glass was clear. As I recharged it got milky bubbles again and solid at full charge.

I know the internet is not the best place for this info, but this site is full of experts on this matter. I will listen and double check advice, but its good to hear from ppl on this forum.

Anyways...its blowing semi-cold at idle, and snowballs at speed. It seems like when Ive got air moving over the engine things work pretty well. I know this is indicative of the ES12A, but I was hoping for a little colder at idle.

How does one drain the oil on 87 300D ? And, do all those cans of ES12A contain oil too? If that the case, no wonder its got too much oil.

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Paul
Benz-less
I need an SDL !

They do say that. I'm of the opinion that they don't know what they are talking about because incompressible gases don't help your AC function and can be detrimental. Their instructions are so vague that you never know if you are correctly following them.

Because of this, I am not considering their product. Certainly you could charge the correct amount of ES12a, followed by a metered charge of fresh air, if it really is necessary for the functioning of the circuit. But they don't tell you do measure the air introduced into the system. Their guidelines can't be correct for all cars.

Of course, you can do what you want with your own car as long as you are also following the applicable laws. But I say, "No thanks" until they get a clue.

About the oil, there is no way to measure or drain oil from the system short of flushing it. I think my system has too much oil in it. I am in the process of flushing the system to replace the oil and ensure the correct quantity.

As to whether the ES12a contains oil, you will have to ask them. Probably not. However, you should ensure that the oil that you are using is miscible in ES12a. It is imperative that this be the case, or the oil will not be returned to the compressor. I'm sure that you know what happens next.

Exceeding 50psi is *NEVER*. But even 50 psi is way too high.

ES-12 does not contain oil. If your system has been charged more than once in the last several years, the refrigerant will evaporate and leave the oils behind. If you do charge the system while under vacuum, your not going to get the coldest air possible because the evaporator will freeze up to fast!

ES-12 is TOO efficient for most systems and when the freeze up starts, your compressor will cylce on and off leaving you getting cold, then hot, then cold, then hot.....see? ES -12 can have the performance characteristics of R22, it can deep freeze really fast.

There is no way to drain out the excessive oil without draining the entire system. You would need to recover the refrigerant and then drain out the oil.

__________________
"Extremism in the defense of liberty is no vice and moderation in the pursuit of justice is no virtue!"

The Greatest Arizona Senator ever, Barry M Goldwater. I hope you can see from heaven how much you are missed.