How Automotive A/C Systems Work

The A/C system in your vehicle uses refrigerant to create cool air through your cabin vents. This is achieved by cycling refrigerant between a heated gas state and a cooled liquid state, which is referred to as the refrigeration cycle. If your vehicle has a refrigerant leak, you may experience poor A/C performance, including intermittent cool air or a complete lack of cooling. The A/C system also uses refrigerant oil to lubricate and seal the various A/C components. A leak in your A/C system can lead to refrigerant or oil loss, which may result in inefficient cooling, A/C compressor failure, or other component failures that will require further repair before the system can be recharged and resume operation.

When performing any car air conditioning repair, it’s important to make sure your vehicle’s A/C system has the appropriate amount of refrigerant and compressor oil. O’Reilly Auto Parts can help you find the right refrigerant and compatible PAG oil viscosity for your car, truck, or SUV. We carry all the heating and air tools and refrigerant supplies you may need, like R134a and R1234yf refrigerant, hybrid and PAG oil, refrigerant leak detectors, sealers, and more.

When recharging your vehicle’s A/C system, always consult your owner’s manual for the recommended refrigerant type and amount, and ensure that you’re using a refrigerant oil that is compatible with your vehicle and its refrigerant. Using the wrong A/C oil or refrigerant can reduce the life expectancy and performance of your A/C compressor, hoses, and fittings. Most vehicles will require R134a or the newer standard R1234yf refrigerant when the system is being recharged. We also carry all major refrigerant oil viscosities, including PAG 46, 100, and 150, as well as R12 conversion kits and adapters for older model vehicles.

In some situations, it might be easier to top off your A/C fluids with an A/C recharge kit. These are all-in-one refrigerant and refrigerant oil solutions that may also offer leak-sealing additives. However, if your A/C system is losing refrigerant, then it’s important to find the source of the leak and repair or replace any failing components. A/C recharge kits are convenient, but may also only be a temporary fix, and can ultimately result in excess refrigerant being released into the atmosphere. Also, it’s common for failing A/C compressors to leave behind metal and plastic shards that may damage other components, hoses, or even new compressors or A/C parts. Therefore, it’s always a good idea to flush the A/C system before recharging to remove any debris or metal particles that may have entered the system, as well as to remove any contaminated oil to ensure a successful repair.

When repairing your vehicle’s A/C system, don’t forget to check all your A/C hoses and components for any signs of leaking refrigerant, and make the necessary repairs before adding any refrigerant to the system. This can help ensure that the new refrigerant is not lost and protects against refrigerant escaping into the atmosphere. O’Reilly Auto Parts carries the most trusted refrigerant leak detectors and sealers for a complete repair. Find all the A/C repair tools you may need, from manifold gauge sets and vacuum pumps to A/C hose disconnect tools, can taps, oil injectors, and other specialty tools. O’Reilly Auto Parts is here to help you get the job done right.

Don’t want to buy a specialty A/C tool for a one-time repair? Shop O’Reilly Auto Parts and take advantage of our FREE auto tool rental & loaner tool program, where you can rent a tool for a refundable deposit at your local O’Reilly store.

Do you need to replace an A/C compressor, evaporator, or other A/C hardware on your vehicle? Check out our complete line of automotive A/C replacement parts and major A/C components for most vehicles, like blower motors, condensers, compressors, A/C hoses, and expansion devices or choose a part category below.

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