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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.

Refrigerant Types & Air Compressor Oils (PAG, POE, Mineral, Etc.)

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R134a Refrigerant R134a Refrigerant
R1234yf Refrigerant R1234yf Refrigerant
PAG Oil, Ester Oil & Lubricants PAG Oil, Ester Oil & Lubricants
A/C System Flushes, Solvents, & A/C Cleaners A/C System Flushes, Solvents, & A/C Cleaners
R12 to R134a Conversion Kits & Adapters R12 to R134a Conversion Kits & Adapters
If you need to recharge your A/C system, our professional parts people can help walk you through this service. This How To Hub video on how to recharge the A/C in a car provides step-by-step instructions and the information you may need to complete a successful recharge.

If you need help with refrigerant disposal, you can find guidelines at EPA.gov

Car A/C Tools

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.

A/C Refrigerant Leak Detectors & Sealers A/C Refrigerant Leak Detectors & Sealers
A/C Manifold Gauge Sets A/C Manifold Gauge Sets
A/C Fan Clutch Wrenches A/C Fan Clutch Wrenches
A/C Vacuum Pumps A/C Vacuum Pumps
A/C Gauges & Specialty Tools A/C Gauges & Specialty Tools
A/C Rental Tools A/C Rental Tools

Car A/C Replacement Parts

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.

A/C Compressors A/C Compressors
A/C Condensers A/C Condensers
A/C Evaporator Cores A/C Evaporator Cores
A/C Accumulators & Receiver Driers A/C Accumulators & Receiver Driers
A/C Expansion Valves A/C Expansion Valves
A/C Orifice Tubes A/C Orifice Tubes
A/C Hoses A/C Hoses

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