if they call for 14 oz, do not put 15 oz. it is better to under-fill than to over-fill.

over-filling by just 10% reduces system efficiency by 40%. don't over-fill!

From Envirosafe: If desired, pull a vacuum to check for leaks. On small AC systems like most passenger motor vehicles - COMPLETELY RELEASE VACUUM BEFORE CHARGING. Unlike freon, ENVIRO-SAFE does not become caustic if moisture is present. Charging under a vacuum on small AC systems may result in an overcharge. Any overcharge may cause loss of cooling efficiency. On dual air systems (some SUVs and vans) and the larger systems found in diesel pusher RVs and Buses should be CHARGED UNDER VACUUM using ENVIRO-SAFE R-134a

When I charged up my cars with the ES stuff I didnt pull any vacuum...

I just plugged in the gauges, started the car, tripped the fans and started filling until the gauges were at pleasing numbers.

I think your low side number is a bit high.. did you measure this number at idle or at high idle (1500rpm)?

With my 190E, I get temps in the low 30s at the vent. My only current complaint is that I lose a considerable amount of cooling performance at a normal idle.

But I'm not sure if thats caused by the refridgerent or the condition of my current system or just an inherent design flaw..

Isn't that too cold? Won't your evaporator freeze up?

Readings were taken at normal idle around 750 rpms. So if my low side is 45 and I'm shooting for 35 what does it indicate and how do I get it down? I think he put in 8 oz. of pag oil, would that be too much? Also if there is too much oil, can the oil be removed with vacuum or does it need to be flushed again?

When I said low 30s, I meant more like mid 30's.. I think it averages around 35-38.

I believe I have a small leak at one of my schraeder valves so I think eventually (slowly) my cooling abilities will diminish..

James, there are tools available from the auto a/c supply houses that allow you to change the schrader valve in a charged system.

At 88 ambient temperature, I'm showing 64 psi low side and 260 psi high side. I'm bringing it back tomorrow morning. Maybe I show try having him vacuuming the system and recharge at a -30 vacuum rather than 0 vacuum??

Thats high for sure! ES-12 is supposed to have similar values are R12 (less 15 psi for the high side)

So what you should be seeing at 88F ambients:

20-24 Psi Low Side
165-215 Psi High Side

You are probably over charged. Either too much ES-12 or too much oil or somthing in the system.

With 12 oz. of ES-12, it should not be overcharged with refrigerant. What is confusing me it Envirosafe recommending charging at 0 vacuum pressure. Would that lead to an overcharged system and higher pressures on a hot installation day? Presumably it will have air in the system at 0 pressure before charging. So hot and so frustrating after you spend good money, arrggghhh! If they don't have a solution in mind, I'm going to ask them to evacuate and recharge at -30 vacuum.

You could try contacting Envirosafe:
Check out this page...
How efficient is ENVIRO-SAFE

My 190E was originally just charged with Freeze12, it eventually leaked out enough that the compressor would not engage. So all I did was open up a can into the a/c system until the gauge pressures were satisfactory. I didnt measure the weight that went in...

Not to muddy the waters anymore but I came across this stuff on the Enviro-Safe website:
http://www.es-refrigerants.com/products/details.asp?id=152&t=air-enhancer&Trying=ON

It sounds interestesting but I've not seen much about it on forums and such.

Thank JamesDean. I spoke to the company and the first tech said I had to drive it for a week or so to work the ES and the oil through the system, I had only driven it like 10 miles or so. A 2nd tech who had been there a long time said that it acted like it was overcharged with 88 ambient, 64 low side, 260 high side. When I explained that the shop only put in 2 cans totaling 12oz in the W123 system requiring 2.33 cans, he didn't know the answer and is going to confer with another tech and call me in the morning. He says that that they recommend charging with 0 vacuum because a little humidity is ok with ES and that charging with a vacuum would call for more ES and could lead to overcharging? Anyways, I'm going to drive it for a few days to see if it gets better before bringing it back to the shop.

I have to really wonder how it is possible to not vacuum and still be able to put any refridgerant in without removing the air first. Air will not do your system any good, it is not a refridgerant, and unless you pull a vacuum it will be in there.

As far as putting too much, weigh it on a digital scale as you put it in, stop when the correct weight is in. unless you are real good at a/c putting it in without weighing it can get you in trouble. I am not an expert by any means but have learned it really is something that should be done by the book, without short cuts.

Yeah, I'm thinking that charging without a vacuum doesn't make sense. Especially when the work is done when it's 90 degrees and humid out the air that you let in to create 0 vacuum is dense and humid anyways.

Does anyone know the guidelines of how much PAG oil to put in a new R4 compressor? The shop put in 8 oz. I talked to Envirosafe and they said one possibility is that there is too much oil in the system. Anybody?