A/C stock temps. What u gettin ??

[Benny771]

What should i aim for ???

For a stock system at 85 outside.
Just checking if mine is up to par.

[GH85Carrera]

At only 85 a stock system should be cold. 45 degree vent temps or so.

[Buckeye]

My system on my 1987 is completely stock including r12 freon. It blows 34 degrees on a 85 degree day. Living in Georgia I have not seen a 85 degree day in a long time

[Benny771]

Cant get r12 anymore .
So i'm using a freon sub. Im getting a 45 degree temp but only while driving for 20min or so.
I have ordered a dryer to see if that helps i dont believe that it has been changed in a long time and several refills.
Hope this helps.
Im getting 55 low side and 230 high (quick test) at 85 with the hood up and after a good run. But the vent temp is 50 while running and increases at a stand still (high 60ish)?
Hoping im on the right track.

[mthomas58]

Originally Posted by Buckeye

My system on my 1987 is completely stock including r12 freon. It blows 34 degrees on a 85 degree day. Living in Georgia I have not seen a 85 degree day in a long time

Excuse me, it was 106 in Atlanta on Saturday........

[88911coupe]

I'm only getting a 30-40 degree drop from whatever the ambient temps are. If it's a 100 (average for Dallas now and the next 2-3 months) I'll only see about 60 at the vents. That's with a procooler AND a large extra condenser with a fan. I'm using ES 12 and have been running about 25-30 on the low side and about 250-300 on the high. I'm trying to figure out if I am under or over charged. It works fine if its been in the garage but any time parked in the sun and it REALLY struggles to get the temps down.

[Benny771]

Your fan ok under the bumper?.. That seems high (vent temp).
I wondering if all this die with ES 12 is an issue?
I have used product like Duracool with no die, and never had a issue in other cars.

[88911coupe]

It's actually in the left rear wheel well. One thing that may be limiting it's effectiveness is that the fan is on the "outside" of the condenser and pulling air through it. This seems to be less than optimal since the air is coming from the cat area. I've considered trying to find a way to flip it but that would require re routing the hoses extensively. I might be able to reverse the fan...have not tried that.

[diabolical]

I get outside ambient temps...

[SilberUrS6]

Originally Posted by diabolical

i get outside ambient temps...

lol.

[kuehl]

Originally Posted by Benny771

What should i aim for ???

For a stock system at 85 outside.
Just checking if mine is up to par.

Vent temps are all relative to the ambient air temp, fan motor speed,
how long the system has been operating, etc.

Since the 911 has such a high heat gain, in simple terms
you want it as cold as you can afford.

[Benny771]

Hoping the new dryer helps, and wondering if the "new" freon that comes in a small 6oz can with die.......
Possible now the system has too much die in it? 7 cans over 3 years or so....

[djcdmv]

Originally Posted by diabolical

I get outside ambient temps...

Me, too.

[kuehl]

Avoid "sealants, enhancers, additives".

[Benny771]

If there is too much dye in the system..... will it settle in the dryer for easy removal ?
If not, where would it settle ?

[JQ911]

Mine is so so! I can feel it blowing cold but not making the whole cabin cold. If it was under the sun for quite a while it takes time to feel the cold air hitting me. I guess mine is not normal based on your testimonials. Its like spring not fall nor winter inside.

[kuehl]

Originally Posted by Benny771

If there is too much dye in the system..... will it settle in the dryer for easy removal ?
If not, where would it settle ?

Fluorescent (meant to be used with a black light) refrigerant dyes are supplied in various size containers: ounce, pints, etc.
The container has refrigerant oil in it and the dye is suspended in the oil.
You can pour dye into the system, such as in a compressor, or inject it with a dye syringe, and automated refrigerant charging systems can inject the dye as well.
You can also purchase small cans of refrigerant (12 oz or 16 oz) that have dye.

You don't need a lot of dye (oil/dye mixture) to find a leak; you need access to visually see the leak and a good black light; doing the procedure in limited light is better than trying to do it daylight.

I have never seen a system that had "too much" dye, maybe too much oil.

Since the dye mixes with the refrigerant oil and the refrigerant oil is moved throughout the entire system by the refrigerant, there will be dye through out the entire system. Some components will tend to hold more oil than others, such as evaporators and driers. If you replace a component then naturally you are removing a percentage of the system oil along with it and hence you need to replace the missing percentage of oil.

I have seen systems with 'sealants' and they do SCREW UP the system, such as blocking pressure switches and expansion valves quite easily. So, if you are DIY and you purchase a product such as refrigerant in cans be sure to read the label to verify what is in the can (avoid sealants).

[Benny771]

Will changing the dryer remove some oil/die mixture?
Does the dryer hold any oil from the system? If so, do you know the amount that it will hold?

[kuehl]

Originally Posted by Benny771

Will changing the dryer remove some oil/die mixture?
Does the dryer hold any oil from the system? If so, do you know the amount that it will hold?

If you replace a component then naturally you are removing a percentage of the system oil along with it and hence you need to replace the missing percentage of oil.


I would safely say if you remove a drier you remove 1 ounce of oil minimum.
The issue we deal with when cars become 20 years and older and have more than 1 owner and more than 1 shop servicing the AC is .... How much oil has been lost over the years? Did anyone add oil over the years?

So, assuming a typical 911/930 two condenser system holds 5 to 6 ounces of oil for discussion purposes. You are converting the system to R134a. You have no clue as to how much oil is in the system. And, you are not replacing all of the components and you are not liquid flushing the system. You are just replacing the drier. In this situation it would be safer to add 5 ounces of refrigerant oil rather than just 1 ounce. Better to assume that there is little oil left in the system then run short and have a compressor grind it self down from too little oil. Ideally, in a perfect world you would flush the two condensers, all the hoses and the evaporator (TEV removed), try to dump what ever oil is left in the compressor and charge the system with 5 to 6 ounces of oil.

If the system used R12 it had 'mineral' oil.
If it was converted to R134a you need to find the documentation as to what kind of oil was used, PAG or Ester. You can mix Ester with mineral oil however there is controversy as to whether you can mix PAG with mineral oil or PAG with ester.
So, if in doubt "throw it out" , flush the system and pick your poison.
We have provided over 1500+ R134a conversion kits over the years using Ester and without any negative consequences.

[Benny771]

Thank-you for the info