How to Retrofit Air Conditioning in Cars to New Refrigerant

PDF download Download Article
PDF download Download Article

If you've need to make a major repair to your car air conditioner such as installing a new evaporator, compressor or condenser, then you can easily update to new refrigerant at the same time. Follow these steps to retrofit air conditioning in cars to new refrigerant, such as R-134a.

Get Car Support Solve Any Problem

wH
Hi there! Do you have a question about how to diagnose or fix a problem with your car? I’ve read the manual so you don’t have to. Select your make, model, and year, then ask away!
*
*
Part 1
Part 1 of 3:

Prep Your System for the New Refrigerant

PDF download Download Article
  1. It's best to have a mechanic do this both for maximum safety and to ensure safe refrigerant disposal. Your mechanic will know the required EPA procedures for removing and getting rid of old refrigerant.
    • Have the mechanic remove any remaining mineral oil from the system. Make sure that the mechanic flushes the system with a solvent that's compatible with R-134a.
    • The mineral oil that is put back into your system should match the old oil. If you had PAG oil, then the mechanic should use PAG oil again. [1]
  2. The desiccant helps to remove moisture that may accumulate in your A/C system.
    • If your A/C system uses an accumulator, you'll find it at the evaporator outlet.
    • You'll find the receiver-drier in systems that use an expansion valve to control refrigerant flow. It's connected to the high-pressure liquid line, between the condenser and the expansion valve.
    • Make sure that your desiccant is compatible with R-134a refrigerant.
    Advertisement
  3. Do this even if you don't think that you need to replace them so that you don't have to do it later if they don't seal.
    • When you remove an old O-ring, tape it to a piece of paper. Write down exactly where that O-ring came from and keep the papers for a while.
    • If you have a leak at a connection, grab the O-ring that you took replaced. Double-check to make sure that you replaced the old O-ring with a new O-ring that was the right size. Most A/C leaks are caused by O-rings that aren't properly installed.
  4. The hoses that you used with the R-12 refrigerant should work as long as they aren't cracked or damaged. If they are damaged, replace them.
  5. When your system pressure gets too high, the cutout switch will shut off the compressor to keep from damaging your A/C parts and to prevent the system from venting refrigerant.
  6. You'll find this tube connected to the high-pressure side at or near the evaporator. In some cases, you may find it in the condenser outlet. Don't try to clean an orifice tube. You'll need to replace it instead.
  7. Make sure to use the viscosity recommended in your car's operating manual.
    8. Advertisement
Part 2
Part 2 of 3:

Add the New Refrigerant

PDF download Download Article
  2. Doing this will puncture the top of the can.
  3. The refrigerant will push air out of the hose so that it doesn't get into your air conditioning system.
  4. Connect the other end of the service hose to the low service fitting on the air conditioner.
  5. You only want vapor to be pulled into your A/C.
  6. The gauge will help you to make sure that your recharge is accurate.
  7. Turn the air conditioner on its maximum setting.
  8. The extraction may take up to 10 minutes. The air blowing from your car vents should grow gradually colder.
  9. When the gauge reads 225 to 250 PSI, close the valve on your refrigerant can. Always close the valve before disconnecting the can so that you don't spray refrigerant into the atmosphere.
    • Generally, your A/C will take in about 12 ounces (355 ml) of refrigerant.
    • If your system isn't fully charged after your refrigerant can is depleted, then you can add another can of refrigerant until your gauge reads in the right PSI range. [2]
    10. Advertisement
Part 3
Part 3 of 3:

Finish the Job

PDF download Download Article
  1. Refrigerant doesn't go bad, so you can use what remains in the can another time. Just make sure to store it in a cool place so that the can doesn't overheat and explode. You can also look into selling refrigerant back to a reclaiming facility or to a certified technician.
  2. Doing this will prevent cross-contamination of refrigerant, and it is required by federal law.
    3. Advertisement

Community Q&A

Search
Add New Question
  • Question
    How do I know what cars need to be retrofitted?
    Community Answer
    Old-style AC ports will have a small port that is threaded compared to a quick-coupler system. Most vehicles switched to r134a in mid-1994.
    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
    Yes No
    Not Helpful 2 Helpful 5
  • Question
    Is there a sight glass on modern receiver/dryers?
    Community Answer
    Some have them but others don't. It depends on your vehicle and its make and year.
    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
    Yes No
    Not Helpful 1 Helpful 2
  • Question
    Can you put r134 in a system that had r12? If not, what do I have to do?
    EddieP
    Community Answer
    No. You cannot add r134(a) refrigerant to an existing system that still contains r12. You can replace the r12 with r134(a) following these steps: 1. A licensed air conditioning technician must discharge and capture the remaining r12 refrigerant. (It is illegal to discharge refrigerant directly to the atmosphere). 2. The system must be flushed to ensure all r12 is removed. 3. A retrofit adapter will need to be installed on the Low and High pressure line fill points. The r12 fill points are threaded fittings and the r134(a) fill points are "push type" fittings. (New condenser and seals may also be needed). 4. Add a new r134(a).
    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
    Yes No
    Not Helpful 0 Helpful 1
Ask a Question
200 characters left
Include your email address to get a message when this question is answered.
Submit
      Advertisement

      Video

      Tips

      • You can purchase a retrofit kit at your local auto parts store if you're not comfortable purchasing the individual parts on your own. Follow the directions in the kit to retrofit your car air conditioner. [3]
        Thanks
        Helpful 0 Not Helpful 0
      • If your A/C stops producing cold air after a short period of time, then you may have a leak. You can use leak detection dye to find the leak. Then, either fix it with a product like Super Seal (if the A/C holds a vacuum for at least 2 weeks) or take it to a mechanic (if your A/C can't hold a vacuum for 2 weeks).
        Thanks
        Helpful 9 Not Helpful 5
      Submit a Tip
      All tip submissions are carefully reviewed before being published
      Name
      Please provide your name and last initial
      Submit
      Thanks for submitting a tip for review!
      Advertisement

      Warnings

      • Be careful to keep your hands and your tools away from moving parts and hot parts of your engine.
        Thanks
        Helpful 4 Not Helpful 0
      • Wear gloves and protective eyewear while working with your air conditioning system. If refrigerant comes into contact with your bare skin, it could cause frostbite.
        Thanks
        Helpful 4 Not Helpful 1
      • Replacing the mineral oil in your A/C system on your own could void your auto warranty. Make sure you know what the consequences will be before you do the work without the help of a mechanic.
        Thanks
        Helpful 2 Not Helpful 3
      Advertisement

      Things You'll Need

      • Accumulator or receiver-drier with O-rings
      • High pressure cutout switch with orifice tube (if required)
      • PAG oil
      • R-134a refrigerant
      • Recharge valve
      • Service hose
      • High-pressure gauge
      • R-134a service fittings for upper and lower service ports

      You Might Also Like

      How to
      Fix Your Car's Air Conditioner
      How to
      Recharge the Air Conditioner in a Car
      How to
      Cool Yourself in a Car Without Air Conditioning
      How to
      Reset a Traction Control Light (TCS)
      How to
      Reset Your Steering Angle Sensor Without an OBD-2
      How to
      Get Out of Limp Mode: 5 Ways to Bypass, Signs, & More
      "Stop Vehicle Leave Engine Running" Mercedes-Benz Warning: Causes & Fixes
      How to
      Fix a Locked Steering Wheel
      How to
      Change an Oxygen Sensor
      What to Do If Your Car’s Anti-Theft System Prevents It from Starting
      Quick and Easy Steps to Reset the Maintenance Required Light
      How to
      Open a Hood with a Broken Latch
      How to
      Fix a Cigarette Lighter in a Car
      How to
      Unlock the Hood of Your Car
      Advertisement

      References

      1. ↑ http://www.e38.org/pparish/flushing.htm
      2. ↑ http://www.aa1car.com/library/ac_recharging.htm
      3. ↑ https://www.acprocold.com/help-and-advice/faqs/

      About This Article

      In other languages
      Thanks to all authors for creating a page that has been read 195,253 times.

      Did this article help you?

      Advertisement