AC Refrigerant: Definition and Updates

By Ryan Mayes

AC refrigerant is 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.

Historically, AC refrigerant has been manufactured using various chemical combinations. Some of the most commonly recognized names include:

  • Freon®
  • R-12
  • R-22
  • R-134A
  • R-410A (Puron®)
  • R-454B (Puron Advance™)

You can learn more about Puron Advance, Carrier’s new refrigerant designed to replace Puron in all residential ducted, ductless, and light commercial products.

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:

  1. Absorbing Heat: The refrigerant circulates through the AC system in a closed loop, alternately absorbing heat from indoor air and releasing it outdoors.
  2. 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.
  3. Compression: The compressor compresses the gas refrigerant, increasing its temperature and pressure.
  4. 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.
  5. 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.

a graphic shows how ac refrigerant passes through air conditioner a graphic shows how ac refrigerant passes through air conditioner

How HVAC Refrigerant Has Changed

There has been a history of innovation and change for HVAC refrigerant. The industry transitions from R-12 to R-22, and subsequently to Puron, aimed to reduce ozone depletion. The most recent shift to Puron Advance focuses on lowering Global Warming Potential (GWP). These changes reflect a commitment to creating solutions that matter for people and our planet.

infographic of ac refrigerant regulation history infographic of ac refrigerant regulation history

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 for ac 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.

chart showing different ac refrigerant classifications chart showing different ac refrigerant classifications

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 troubleshooting, repair, or replacement with a new, higher efficiency HVAC system.

Frequently Asked Questions

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.

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