How to Retrofit Air Conditioning in Cars to New Refrigerant

Steps

1. 1
   Skip to step 4 if your car is a '96 model or newer, If your car is a '95 model or older, continue reading. Many GM models from '94 on are R134a and would fall under the '96 and newer category. To verify, look under the hood of the car for a label that will tell you what refrigerant the system uses.
   
   
2. 2
   Have the freon (R12) still in the system evacuated with a recovery machine by a licensed professional.
3. 3
   Buy a "dryer" at an auto parts store, and replace the original in your car. A sales rep in the store can tell you where the dryer is and how to change it out.
4. 4
   Replace the dryer. Remember to replace the "o" rings supplied with the new dryer.
5. 5
   Go to your nearest auto service center and ask them to vacuum down your A/C system (at a cost of approximately $5-15). This process removes atmosphere from the system.
6. 6
   On existing R-12 systems you might want to consider a replacement refigerant -- next step or if not, Purchase an A/C retrofit kit for R-134a refrigerant ($30) at your local auto parts store. Also purchase enough refrigerant to fill your system (the sales rep can tell you how much you need). Do not forget to buy a can of "oil charge" for your A/C system. Failure to do so will sieze your compressor, necessitating a $500+ repair. Most Retrofit kits comes with enough R-134a and oil in the kit to complete the job.
7. 7
   Explore using a substitute for R-12 systems. There are other refrigerants available that are superior to R-134 for use in older R-12 systems and may also be used in R-134 systems. In general, they are cheaper than R-134. However, be aware that some of these are based on flammable gases. Since your fuel system is also pressurized, that would be an equivalent or worse fire hazard. There are several EPA accepted R-12 replacements, check with the EPA web site for specific approved products (Freeze 12 is a good one.)
8. 8
   Connect the kit to your car, referring to the supplied instructions.
9. 9
   Start the car and turn the A/C on full blast. Use the kit to add the oil charge first, and then the refrigerant that your car needs. Be careful not to overfill. Note: Never try and heat up a can of R-134a by placing it in a pan of warm water. This is very dangerous and can cause the can to explode. Never try to retrofit or recharge the A/C system when the temp. is below 65 degrees.
10. 10
    Keep the car running, and check to see if it produces nice cold air. If it's not really cold, you need to add more refrigerant. For best results always use a gauge and fill to the correct PSI level. You can find the R-134a System Pressure Chart on http://www.idqusa.com under Diagrams and Specs. It is highly recommended to use gauges to monitor the pressure on your AC system. If you don't, you may blow a seal costing lots of money to fix!
11. 11
    For more details on the above procedure check out this site: http://www.aa1car.com/library/ac_recharging.htm
    
    

Tips

• It it illegal and harmful to the environment to release refrigerant into the air.
• DO NOT forget to get your A/C system evacuated prior to adding new refrigerant. R-12 refrigerant (freon) DOES NOT MIX with R-134a refrigerant (the new stuff). Failure to do so will cause the "black death syndrome" in which the conflicting refrigerants will turn into a black goo that clogs your entire A/C system, resulting in a $900 plus repair.
• DO NOT FORGET to REPLACE YOUR DRYER in cars '95 model year and older. Failure to do so will result in the "black death syndrome" as well.
• Follow instructions that come with your retrofit kit and you will be fine. Most retrofit kits do not require you to open your A/C system and replace any components. As long as your system is running well before retrofitting.

Warnings

• Be careful to keep hands and tools away from moving parts and hot parts of your engine.
• It it illegal and harmful to the environment to release refrigerant into the air.

Things You'll Need

• Adjustable wrench
• Retrofit kit (allows you to connect to your A/C system and add refrigerant and oil charge)
• R134a refrigerant (explore using a substitute R-12)
• Oil charge
• New dryer ('95 model year and older)

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