How to Retrofit Air Conditioning in Cars to New Refrigerant
Make sure that all of the old refrigerant has been vacuumed out of your air conditioning system., Install an accumulator or receiver-drier that contains desiccant., Replace the O-rings, which are usually found at every connection., Double-check your...
Step-by-Step Guide
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Step 1: Make sure that all of the old refrigerant has been vacuumed out of your air conditioning system.
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. -
Step 2: Install an accumulator or receiver-drier that contains desiccant.
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., 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., 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. , 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., 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. , Make sure to use the viscosity recommended in your car's operating manual.,, Doing this will puncture the top of the can. , The refrigerant will push air out of the hose so that it doesn't get into your air conditioning system. , Connect the other end of the service hose to the low service fitting on the air conditioner. , You only want vapor to be pulled into your A/C. , The gauge will help you to make sure that your recharge is accurate. , Turn the air conditioner on its maximum setting. , The extraction may take up to 10 minutes.
The air blowing from your car vents should grow gradually colder. , 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., 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. , Doing this will prevent cross-contamination of refrigerant, and it is required by federal law. -
Step 3: Replace the O-rings
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Step 4: which are usually found at every connection.
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Step 5: Double-check your hoses.
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Step 6: Install a high-pressure cutout switch if you don't have one or replace your old one.
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Step 7: Check the orifice tube.
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Step 8: Add the appropriate PAG oil if your mechanic did not.
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Step 9: Connect the recharge valve and service hose to your refrigerant can.
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Step 10: Turn the valve on the service hose.
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Step 11: Twist the valve back out slowly to release a little bit of refrigerant into the hose.
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Step 12: Close the valve to keep more refrigerant from escaping.
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Step 13: Hold your refrigerant can upright so that the A/C doesn't suck liquid into the system.
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Step 14: Attach a high pressure gauge to the high service port.
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Step 15: Start your car engine.
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Step 16: Open the valve on your refrigerant and let the A/C extract vapor from the can.
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Step 17: Watch your high pressure gauge.
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Step 18: Store your refrigerant can with the service hose attached.
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Step 19: Install R-134a fittings on the upper and lower service ports.
Detailed Guide
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.
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., 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., 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. , 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., 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. , Make sure to use the viscosity recommended in your car's operating manual.,, Doing this will puncture the top of the can. , The refrigerant will push air out of the hose so that it doesn't get into your air conditioning system. , Connect the other end of the service hose to the low service fitting on the air conditioner. , You only want vapor to be pulled into your A/C. , The gauge will help you to make sure that your recharge is accurate. , Turn the air conditioner on its maximum setting. , The extraction may take up to 10 minutes.
The air blowing from your car vents should grow gradually colder. , 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., 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. , Doing this will prevent cross-contamination of refrigerant, and it is required by federal law.
About the Author
Brian Hughes
Experienced content creator specializing in creative arts guides and tutorials.
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