Adding Freon to your automobile's Air Condtioning system

Every automobile parts store I walk in these days has freon for sale. When R-12 was around I was licensed to buy and use it. I thought that was a good thing because you can be severely injured and or do $$ of damage to the system your working on. I decided I would do this instructable for the following 2 reasons . First to help people to understand and be safe. Second to equip you to make a repair to your AC system if it just needs a Freon charge to bring it back to good working order. First a few Rules you need to always follow.
1. Since your car engine is running to charge the AC system there are moving belts and pulleys,fan(s) and very hot parts. You can easily loose your fingers if you put them where they don't belong!
2. Freon if sprayed as a liquid on your body parts will freeze them instantly- FROSTBITE
3.Don't release freon into the atmosphere. It is not good for the earth.
4.Wear safety goggles at all times incase a hose blows or something goes wrong and freon is sprayed on your face.
5. If after reading this instructable you feel unsure about doing this then you should not be doing it.
THIS CAN BE DANGEROUS AND THERE IS POTENTIAL FOR INJURY. I ASSUME NO LIABILITY FOR YOUR TRYING THIS. THIS IS JUST A DEMONSTRATION OF HOW TO DO IT. IF YOU DECIDE TO DO IT YOU DO SO AT YOUR OWN RISK.
Ok lets get started.
Tools needed:
1. The adapter to connect from the freon can to your freon SUCTION SIDE of the AC system.
Found where you buy freon.
2. Freon- probably 2 cans if your system is barely cold. If it is cool but not as cold as it was buy 1 can
3. A thermometer to see the temp drop from the dash vents or cold air out.
4. An AC system in need of some freon.

Step 1 Install the hose on can

We now make sure the pin in the tool is backed out so we cant see the point. We install the hose tool on the can. The can is not punctured. Once you screw the pin down into the can you can not remove the hose tool until the can is empty.When you screw the pin in to the can the pin seals in the freon. The other end of the hose also has a safety seat built in it so if the pin is backed out it will not vent freon to the atmosphere.
AS LONG AS THE CAN IS UPRIGHT ONLY VAPOR COMES OUT OF THE HOSE
IF THE CAN IS UPSIDE DOWN LIQUID COMES OUT SO KEEP IT RIGHT SIDE UP!
I spent a lot of time on this simple step but that was so you do this SAFELY.

Comments

[philheflin]

How much 134A is needed in a 1967 Camaro 327? Thanks. Phil

[Derin]

How would I be able to remove A/C from a car?

[skunkbait]

Hey, you did a gret job on this ible. Five Stars! I was intimidated by A/C systems until a couple of years ago. I had to make a trip to New Orleans (in August!) and my Suburban's A/C had just crashed (compressor). I had one day to figure it out or burn up. Necessity is the mother of A/C repair!

[Gort]

Thanks. Good for you for not giving up and figuring it out. Don't things just pick the worst time to break?..lol

[Derin]

I know...the brakes on our VW failed right when we were about to go home which was 50m away...had to take it to two service stations because one didnt have the part.

[Derin]

NEVER;EVER touch the fan if its not unplugged.I have seen cars that are off and still have the fan running full blast.

[Gort]

As a side note you can dust talcum or baby powder onto the accumulator and then easily watch for moisture accumulation on it.

[PATSY001]

Not trying to be petty, however "Freon" was just a brand name used by the DuPont corporation. The appropriate term to call such substance would be "Refrigerant". The term refrigerant can refer to all the different types such as R-12, R-22, R-134a etc.(and many more). But most importantly true Freon is composed of chlorofluorocarbons.

[Gort]

Your right.
My intended audience for this was folks who wanted to get their system going but really did not understand what was going on behind the scenes. Nine times out of ten if you walk into a parts store and ask the counter guy "I need some of that stuff that makes your AC cold" The guy will say "you mean freon and its over there." Freon is the accepted street name if you will and most people recognize That name. Take a look at this big chain auto parts seller's web page and see how they identify refrigerant on their web site
http://www.autozone.com/N,101308/shopping/accessoriesLanding.htm

[PATSY001]

Yes, I see your point, but that is not right. Not even for large corporations, unless it is manufactured by DuPont, but even they don't call it that anymore. Not picking on you, but maybe someone could make a buck or two by letting DuPont know someone is "ripping off" (using without permission) their trade name. Like for example if you invented the "Gort" recharger, and someone else marketed a similar product, and called it a "Gort" ... you should get millions due to inventors rights and copyrights... but maybe now I'm just being silly. But someone out there should offer their legal services to DuPont against "un-named big name auto parts store" hint hint... if anyone does this, keep Patsy001 in mind for compensation of his idea.

[Gort]

It's your idea ..have at it

[thematthatter]

Is there a concern about accidentally putting moisture in the system when you recharge it?

[Gort]

Moisture will cause freezing of your system. Usually at the expansion valve which is where the freon escapes high pressure into low pressure through a tiny orifice. Moisture likes to freeze that orifice closed. It will unfreeze in about 10 minutes and your ac will work again. 134A boils around -15 degrees F. So its very cold at the expansion valve and that is why you don't want moisture. The oil in the compressor also likes to absorb the moisture and this can cause it to go acid over time.All AC systems have a "drier" in them. That is a powerful chemical that absorbs and holds any moisture. If you accidentally allow moisture in your system most likely there will be absolutely no problem because the drier will immediately grab it. But I wanted everyone to know the correct procedure. The quick answer to your question is don't lose any sleep over it. In my summary you noticed I stated that if after you charge your system it goes from cold to warm over and over its probably moisture. Remember that when an AC system is recharged by non pros they have no way of knowing if their system is moisture saturated or not. On older cars there was a little view window on top of the receiver / drier and if it was blue you were good if it turned pink you were moisture saturated. If you have a leak and lose ALL your freon then the drier will actually pull" outside of the system" moisture in through the leak path and saturate itself. Then when you Recharge it there is moisture mixed with freon and that is a major problem in terms of it working as it should.