Choosing an environmentally friendly refrigerant is one of the most important ways modern HVAC systems can reduce environmental impact while still delivering reliable cooling.
In this blog post, Carney & Son 72 Degrees will discuss some of the best environmentally friendly refrigerants on the market and how you can use them in your HVAC system responsibly!
Quick Answer: 5 Environmentally Friendly Refrigerants for HVAC
Environmentally friendly refrigerants typically have lower climate impact (lower GWP) than many older high-GWP refrigerants, and some also avoid ozone damage compared to older chlorine-containing refrigerants like CFCs and HCFCs. In HVAC, lower-impact options can include HFO-based blends, CO₂ (R-744), ammonia (R-717), and hydrocarbons like propane (R-290) and isobutane (R-600a), but what’s “common” depends heavily on the application because several of these are far more common in refrigeration or industrial systems than in typical residential comfort cooling. The right choice depends on equipment design, safety class, and local availability.
Comparison Table: Environmentally Friendly Refrigerant Options
Important: Refrigerants are not “mix-and-match.” Never add or swap refrigerant types unless the system is specifically designed and approved for that refrigerant. In the U.S., EPA SNAP listings and related federal requirements limit where specific refrigerants may be used, and flammable or mildly flammable refrigerants must be used only in equipment designed and listed for them and in approved end-uses.
If you want quieter operation, better efficiency, and equipment designed around today’s refrigerants, start here:
What Refrigerant Is in My System?
The safest way to confirm your refrigerant is to check the equipment data plate (usually on the outdoor condenser) or a service label placed by a technician. You may also find it in your owner’s manual or original install paperwork. If you’re unsure, a licensed HVAC technician can identify it during inspection without guesswork.
Do not open sealed system components to look for refrigerant, and never top off a system unless the correct refrigerant type is confirmed first.
Why You Need a Licensed Tech (EPA Section 608)
Refrigerants are regulated, and handling them requires training, proper recovery equipment, and certification. Under EPA Section 608, technicians who maintain, service, repair, or dispose of equipment that could release refrigerants into the atmosphere must be certified. This protects you, your equipment, and the environment.
Safety disclaimer
- Refrigerant work is not DIY.
- Using the wrong refrigerant, mixing refrigerants, or charging incorrectly can damage equipment and create safety hazards.
- Flammable or mildly flammable refrigerants must only be used in systems designed and approved for them
History Of Harmful Refrigerant Effects On The Environment:
Chlorofluorocarbons, CFCs or Freon, are a group of man-made chemicals that were once commonly used in refrigerators, air conditioners, and aerosol cans. However, freons were found to damage the Earth’s ozone layer, protecting us from harmful ultraviolet rays. As a result of this discovery, the production of CFCs was banned in many countries in the late 20th century.
Hydrofluorocarbons (HFCs) or another brand of freons are a group of man-made chemicals developed to replace CFCs. While HFCs do not destroy or harm the ozone layer, they are potent greenhouse gases that trap heat in the Earth’s atmosphere and contribute to global warming.
Global Warming Potential (GWP) tool:
In response to the toxic effect, a timeline for the phase-out of chlorine-based refrigerants was established by the 1987 Montreal Protocol and subsequent accords. The Global Warming Potential (GWP) tool was created to gauge and compare how refrigerants and other compounds affect the atmosphere and consequent global warming. Rating refrigerants according to their GWP values enables harmful gases with high GWP values to be phased out while promoting those with lower GWP values as replacements.
5 Environmentally Friendly Refrigerants:
Fortunately, several environmentally friendly refrigerants can be used in place of CFCs and HFCs. These refrigerants include:
1. Hydro-fluoro olefins (HFOs):
HFOs are a type of fluorocarbon, but they do not contain chlorine or bromine and are therefore much less damaging to the environment.
Few of the HFOs include R449A and R454C.
2. Carbon dioxide (CO₂):
CO₂ is a naturally occurring gas used as a refrigerant for many years. It is non-toxic and does not contribute to ozone depletion. CO₂ is a very efficient refrigerant, but it can only be used in applications where the temperature is below 78 degrees Fahrenheit.
3. Ammonia (NH₃):
Ammonia has been a refrigerant for over 100 years and is still used today. It is very efficient and has a very low impact on the environment. Ammonia is also very inexpensive, making it a great choice for businesses looking to save money.
However, its flammability limits its widespread use.
4. Isobutane (C₄H₁₀):
Isobutane, which is stable and comparable to its predecessors in performance and environmental effect, has a very low GWP value of just 3. It is now among the most regularly used refrigerants for residential, commercial, and industrial refrigeration.
5. Propane (R-290)
Propane (R-290) is a hydrocarbon refrigerant that is gaining traction in certain commercial refrigeration and specialty cooling applications because it has very low global warming impact compared to many legacy refrigerants. In properly engineered equipment, R-290 can deliver strong performance and efficiency.
That said, propane is classified as A3 (highly flammable), which means it must only be used in systems specifically designed and approved for it. It is not a simple “drop-in” replacement for typical residential central air systems. A licensed HVAC professional can help determine whether propane-based equipment is appropriate for your application and ensure it is handled safely and legally.
Professional HVAC contractors like Carney & Son 72 Degrees, serving Goose Creek, Charleston, and the surrounding areas, can help you with refrigerants. Whether you want assistance with HVAC installation or maintenance, our air conditioner specialists are the solution.
Please book a consultation with us today!
