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Discussion Starter #1
The past few weeks we had temp in the 90's here and I've notice its take about 30 mins for the AC to kick in. I've talked to a few people about this and was told they had the same issue, and had someone add freon to their AC system to resolve it.

I've checked some local auto service center for AC service and found price ranging from $99 - $149. Also I saw on Autozone's web site there is a freon charging kit for $40.

Has anyone done this before? Or is there any instructions on how to do this?

Also I did try Warhammer's trick to insulate the AC line already.

Thanks in advance.
 

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I suspect a slow leak if your ac takes 1/2 hour to kick in. Those kits have a guage that tells you if you are low in freon. It comes with instructions and you add the freon on the low pressure side. There is a valve in the area where you covered you pipes with the foam. It will be best to get a pressure test on the system. This way you will fix it for good. Those auto ac shops sometimes got deals on pressure checking the ac system for free if you have them fix it if there is a leak. Ask for the cost up front first though.
 

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Some background: Freon is a term for a class of chloroflurocarbons (commonly R-12) which is no longer used in auto AC systems. Most now use R-134A (a kind of tetrafluoroethane) which I haven't heard referred to as ""freon", although it's likely that term is still used coloquially. At any rate, R-134A is what you would find in auto parts stores.

R-134A has a smaller molecular structure than R-12, and is therefore slightly more prone to leakage. I STRONGLY recommend that you take the car to an AC shop (not the dealer) and have them do a leak test, then fill it for you. The cost should not be very high, and it will be done right.

I decided some time ago not to just slap a filler gauge set on my AC and mickey-mouse it. I leave the AC recharge work to people who really understand the systems.

I do replace my own AC components or even complete systems (done it on three cars and saved a ton of money) but when it comes to re-charge time, I take it to a pro.
 

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Discussion Starter #4
Thanks for the replies ...

I got this fixed this weekend.
On Friday I took it to get a free AC test -
no leaks were found however was told the freon level was at min level, was told this is normal with the mileage (128k) since the AC was never serviced

On Saturday I had some free time and decide to drain/flush/refill anti-freeze and also added freon, just below the max. Low pressure line is still insulated

It was 96 Degrees here in Atlanta, and the AC felt colder then ever.
 

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Can you post the diy in adding the freon. I am now thinking in adding some in my ac which has not seen service yet either. But I only have 72k on my '04. However, vegas heat makes me always want colder air. It may need topping off as well--even just a little.
 

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Adding refrigerant (let's not call it Freon, since its Freon is not used anymore, its R134a now) is not something you can generally do on your own unless you have the necessary equipment - the "recharge kits" they sell at auto parts stores are a booster only, and there really isn't a way to tell if the system is fully charged or not with the cheap gauge they supply. A professional shop will fully evacuate the system, capture the old refrigerant, recycle it, and fill the system to capacity with new R134a.
 

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Glad to hear that your AC system is working again! The only question I would have for the technician is this: If my freon levels are low, and you say I don't have any leaks, then how did my freon get out of this sealed system? Or does freon these days just get tired or break down to where it doesn't work any more.

It would be interesting to see the difference in AC performance if only the Arctic Freeze stuff were put into the system. The company claims that the AC will put out colder air and will get colder faster upon start up. Anybody ever use this stuff?
 

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As I mentioned above, R134A is a smaller molecular structure than R12 was, and therefore over time it generally leaks more readily even if there are no flaws in the system. Systems will vary, and some will hold better than others. More frequent charges are just part of the price we pay.
 

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Glad to hear that your AC system is working again! The only question I would have for the technician is this: If my freon levels are low, and you say I don't have any leaks, then how did my freon get out of this sealed system? Or does freon these days just get tired or break down to where it doesn't work any more.

It would be interesting to see the difference in AC performance if only the Arctic Freeze stuff were put into the system. The company claims that the AC will put out colder air and will get colder faster upon start up. Anybody ever use this stuff?

I was looking at the quest co website and actually thinking of using the subzero can. IDQ - Auto A/C Products & Sealing Solutions

Key question is how to know if you put in enough without overfilling. Estimating by using the pressure guage and the can capacity is all you have.

Here is a video of a guy using it.
 

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The video ads to my limited knowledge of the PSI readings on AC systems. In other words, after turning on your AC system to the maximum setting, make sure that the PSI reading is correct with respect to the compressor being on. When the compressor turns on, observe the PSI reading. If the PSI reading is below expected values, add the freon little by little until the PSI reading is correct.

It looks easier than I was making it. I tend to overcharge systems when I went to recharge in the past which made me a bit gunshy. I have one of these meters at home so I'll check my AC pressure levels to see what they are.

Do you have to compensate for a hot engine bay? Or is it with respect to ambient outside temperature only?
 

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Checked my low side yesterday afternoon and it sits right at 35PSI while the compressor was on. Looks good!

The only concern is that it was like 95 degrees outside. Should I add more freon to bring it up to 45PSI? Or should I leave it alone?
 

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Discussion Starter #15
Checked my low side yesterday afternoon and it sits right at 35PSI while the compressor was on. Looks good!

The only concern is that it was like 95 degrees outside. Should I add more freon to bring it up to 45PSI? Or should I leave it alone?
Mine was reading 30PSI so I used the Arctic Freeze and recharge it to about 42-43PSI.
 

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Was there instant coldness in the air? What was your ambient temp. approx.?
did you just follow the video instruction? Did you add little by little checking the psi everytime?
 

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Hey DJFRDJR -- Did you notice your AC get colder? Your PSI reading should be on the upper scale of full right?
 

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Just to make sure, I get two readings when using the can pictured in the post (the Arctic Freeze can with included pressure gauge).

I want to ensure that I use the right reading when charging. When the compressor kicks in, the reading goes down in the 20s, and therefore needs some charging. When the compressor turns off (for about three seconds), the pressure returns back into the "normal" range and therefore indicates that I don't need to add any more 134a.

Which reading do I trust? When the compressor is going? If so, then if I raise that range into "normal" with the gauge, then when the compressor is NOT engaged, the reading will be in the "warning" range of yellow. Before I do this, I want to make sure that is how it should be...
 

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Just to make sure, I get two readings when using the can pictured in the post (the Arctic Freeze can with included pressure gauge).

I want to ensure that I use the right reading when charging. When the compressor kicks in, the reading goes down in the 20s, and therefore needs some charging. When the compressor turns off (for about three seconds), the pressure returns back into the "normal" range and therefore indicates that I don't need to add any more 134a.

Which reading do I trust? When the compressor is going? If so, then if I raise that range into "normal" with the gauge, then when the compressor is NOT engaged, the reading will be in the "warning" range of yellow. Before I do this, I want to make sure that is how it should be...
The instructions say to have the A/C on MAX A/C which is designed to have the compressor running. So I would say you need to add some since your pressure is down to 20. 40-45 when the compressor is running should be good assuming your temps are in the 80's. If you aren't confident, add till you get to no more than say 38-40. Remember, YMMV. Check the gauge and your ambient temps and do what the can says.
 
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