AC Refrigerant: Types, Definition and Updates
Carrier defines AC refrigerant as a chemical compound used in air conditioning and heat pump systems to absorb heat from indoor air and release it outside, effectively cooling your home. It transitions between liquid and gas states within a closed loop to regulate indoor temperature.
You may not know this, but for virtually every person in modern society, refrigerant touches your life nearly every day. That cold beverage from your refrigerator, the cool breeze from your car’s air conditioning vents, and even that warm air from your heat pump are all courtesy of refrigerant.
Refrigerant has been a vital part of indoor cooling systems since Willis Carrier invented the modern method of conditioning air in 1902. If you are reading this in the middle of summer, you are likely doing so in the air-conditioned comfort provided by this essential technology.
What is AC Refrigerant?
In technical terms, what is refrigerant? It is a specialized fluid capable of transitioning from liquid to gas and back again. During this phase change process, its ability to absorb and transfer heat has been the key to cooling, refrigeration, and heat pump systems for over a century.
Refrigerant Types
Historically, AC refrigerant has been manufactured using various chemical combinations. Some of the most commonly recognized refrigerant types:
- Freon®
- R-12
- R-22
- R-134A
- R-410A (Puron®)
- R-454B (Puron Advance)
Different types of refrigerant have been used in air conditioning systems over the years, with newer options developed to meet changing environmental regulations and performance requirements. R-22 and R-410A were widely used in residential AC systems, while newer systems increasingly use lower-global-warming-potential refrigerants such as R-454B.
Comparing R-22, R-410A and R-454B Refrigerants
Air conditioner refrigerants have changed over time as regulations have addressed ozone depletion and global warming potential (GWP). Carrier's newer residential systems use R-454B, also known as Puron Advance™, as the industry transitions away from R-410A.
| Refrigerant | Years in Use | GWP | Ozone Depletion Potential | Current Status |
| R-22 | Primarily used in residential AC systems through the 2000s | 1,810 | Yes | Phased out for new U.S. equipment; reclaimed/previously produced R-22 may still be used to service existing systems |
| R-410A | Approximately 2010–2023 for widespread residential use | 2,088 | 0 | Being phased out for new residential equipment; existing systems can still be serviced |
| R-454B | 2024-present | 466 | 0 | Lower-GWP refrigerant for newer residential AC and heat pump systems |
*Years in use are approximate and refer to common U.S. residential HVAC applications, not the first or last year the refrigerant existed.
How AC Refrigerant Works
Whether you call it refrigerant, Freon, R-22, R-410A, Puron, or something else, the function remains consistent. As a part of your air conditioner or heat pump system, it helps transfer heat and humidity out of your home for cooling or draws heat from outdoor air and brings it inside for heating.
AC refrigerant plays a crucial role in the cooling process of air conditioning systems. Here is the step-by-step process:
- Absorbing Heat: The refrigerant circulates through the AC system in a closed loop, alternately absorbing heat from indoor air and releasing it outdoors.
- Phase Change: As the refrigerant passes through the evaporator coil indoors, it absorbs heat from indoor air, causing it to evaporate from a liquid to a gas.
- Compression: The compressor compresses the gas refrigerant, increasing its temperature and pressure.
- Condensation: The hot, high-pressure gas refrigerant then flows to the condenser coil located outside or in the outdoor unit. Here, it condenses back into a liquid state, releasing the heat it absorbed from indoors to the outdoor air.
- Expansion: The liquid refrigerant passes through an expansion valve or capillary tube, where it undergoes a pressure drop, allowing it to evaporate and absorb heat again in the indoor evaporator coil, restarting the cycle.
David Clendennen, owner of Clendennen Service in Marble Falls, Texas explains the important role refrigerant plays in an air conditioning system’s operation.
“The refrigerant is like the blood of the HVAC system,” Clendennen said. “It has to stay clean and function properly to do its job effectively. Refrigerant absorbs heat from inside the home and carries it outdoors. To do that efficiently, it has to circulate properly and operate under the correct pressures.”
For a deeper dive into the mechanics, read about how do air conditioners work.
How HVAC Refrigerant Has Changed
There has been a long history of innovation and change in HVAC refrigerants. The industry transitioned from R-12 to R-22, and later from R-22 to R-410A, known by Carrier as Puron®, as regulations targeted ozone-depleting refrigerants. The EPA phased out production and import of new R-22 in the U.S. beginning in 2020, while allowing existing R-22 systems to continue operating and be serviced.
The latest transition focuses on reducing the global warming potential (GWP) of refrigerants. Under the American Innovation and Manufacturing (AIM) Act and EPA's Technology Transitions Program, EPA established restrictions on higher-GWP HFCs used in residential and light commercial air-conditioning and heat-pump equipment. For residential and light commercial AC and heat-pump systems, the rule establishes a GWP limit of 700, with the applicable compliance requirements beginning January 1, 2025, subject to provisions for equipment manufactured or imported before that date.
This transition is driving the industry toward lower-GWP refrigerants such as R-454B, including Carrier's Puron Advance™ refrigerant. These changes reflect continued innovation in HVAC technology and efforts to develop solutions with lower environmental impact.
Regulatory reference: EPA's HFC Technology Transitions requirements are codified in 40 CFR Part 84, Subpart B, including 40 CFR § 84.54, which establishes restrictions on the use of certain HFCs in residential and light commercial air-conditioning and heat-pump systems
What HVAC Refrigerant Means to You Now
Because air conditioning and heat pump systems can last 15 years or longer, there are still many systems in service today that utilize older refrigerant types. Here is what you need to know based on when your system was installed.
If your HVAC system was installed in 2010 or before
- You likely have a system with R-22 refrigerant.
- Only “used” or “reclaimed” R-22 is available for system repairs or recharging as of 2020.
If your system was installed between 2010 and 2023
- You probably have a system with R-410A, Puron, or an equivalent, non-ozone depleting refrigerant.
- In the short term, the cost for adding refrigerant to your system should remain somewhat stable due to ample supplies.
- Due to potentially escalating costs for repairs and the phasedown of R-410A refrigerant, it may be more economically sound to replace an ailing air conditioner or heat pump with a new model that uses Puron Advance.
If your system was installed in 2024 or beyond
Puron Advance is Carrier’s new refrigerant that has replaced Puron in all residential ducted, ductless, and light commercial products. This refrigerant, also known as R-454B, meets the Environmental Protection Agency’s (EPA) anticipated Global Warming Potential (GWP) limits for refrigerants and the scheduled phasedown of higher GWP refrigerants like Puron™ or R-410A.
Effective January 1, 2025, all newly manufactured or imported HVAC indoor units, outdoor units, SPP, Mini-VRF, VRF, and light commercial products must be designed for use with a low GWP refrigerant. Puron Advance not only meets but exceeds the new requirement with a GWP of 466 and is a 75% reduction in GWP compared to R-410A.
Talk to Your Local Carrier Dealer for Your AC Refrigerant Needs
If your current system is struggling to keep you cool, running low on refrigerant is just one of many potential issues. The problem could be as simple as a clogged filter, or a more complicated issue with your unit’s compressor. The best way to find a solution is to contact your local Carrier HVAC contractor for professional AC service, AC repair, or AC replacement with a new, higher efficiency HVAC system.
Frequently Asked Questions
Carrier strongly recommends leaving adding refrigerant to your home AC to a professional. Improper handling can lead to system damage, safety hazards, or voided warranties. A certified HVAC technician can safely check for leaks and ensure the correct refrigerant for AC is used.
The refrigerant used depends on the system's age. Systems from 2010 or before typically use R-22. Systems installed between 2010 and 2023 generally use R-410A (Puron). Systems installed in 2024 or beyond will likely use Puron Advance (R-454B), which has a lower Global Warming Potential.
Yes, using the correct AC refrigerant is critical. Each type has specific chemical properties, and using the wrong one can damage the compressor, reduce efficiency, or void warranties. Always use the refrigerant specified by the manufacturer.
Using the wrong refrigerant can cause inefficient cooling, increased energy consumption, and catastrophic system failure. It may also create safety hazards due to incompatible chemical pressures.
Effective January 1, 2025, the manufacturing of new residential systems using high-GWP refrigerants like R-410A is restricted. While existing systems can still be serviced, HVAC manufacturers like Carrier are moving to low-GWP alternatives like R-454B.
AC refrigerant does not expire and is part of a closed-loop system, meaning it should not need to be refilled unless there is a leak. If your system is low on refrigerant, it indicates a leak that requires professional AC repair from a Carrier dealer.
About The Author: Ryan Mayes is a Senior Digital Brand Marketing Manager at Carrier who focuses on creating clear, helpful resources on HVAC topics. Ryan’s goal is to guide readers toward smart, confident decisions about their indoor comfort.