Climate-Friendly Alternatives to HFCs and the Rise of A2L Refrigerants
In 1987, a coalition of nations signed a treaty known as the Montreal Protocol. This agreement led to the banning of refrigerants responsible for the depletion of the ozone layer. Throughout the 1990s, ozone-harming chemicals were phased out in favor of a new chemical: hydrofluorocarbons, or HFCs. However, even though the use of HFCs was much better for the ozone layer, they had side effects. Since then, scientists have discovered that HFCs contribute thousands of times more to global warming than CO2. So, many companies are looking for alternatives to HFCs. Entire A2L refrigerants and their growing popularity around the world.
Saying Goodbye to R-22 and R-410A
R-22 has been illegal to produce and use in the United States since January 1st, 2020. R-410A, its replacement, is in its final stages of use and is slated for phase-out by 2023.
Technicians will have to become familiar with new refrigerants that are more climate-friendly. In addition, many existing systems will have to be converted or discarded entirely as eco-friendly refrigerants increase in the marketplace.
More Environmentally Sound Alternatives to HFCs: A2Ls
According to ASHRAE Standard 34, there are two classifications of toxicity for refrigerants:
- A, lower toxicity
- B, higher toxicity
The standard also sets flammability classes:
- Class 1: Cannot propagate a flame
- Class 2: Low flammability
- Class 2L: Covers Class 2 refrigerants with slow-burning capacity
- Class 3: Highly flammable
Class A2L covers refrigerants that are low in toxicity but have some level of flammability. A2L refrigerants are part of the hydrofluoro-olefin (HFO) family, which are compounds of hydrogen, fluoride, and carbon. HFOs, while slightly flammable, are also far better for the atmosphere.
Some specific R-22 and R-410A alternatives include:
- R-1234yf: Automotive AC systems use this refrigerant. It comes with a Global Warming Potential (GWP) of 4. For context, R-22 carries a GWP of 1,810.
- R-32: This is one of the more common R-410A replacements and comes with a GWP of 675, which is 30% lower than R410A. Systems that use R-32 also use 20% less refrigerant.
- R-454B: Compared to R-410A, R-454B is more efficient at the same capacity and has a GWP of 467.
- R-452B: R-452B features a lower mass flow rate when compared to R-410A and a comparable exhaust temperature. It has a GWP of 676.
- R-454A: This has a GWP of 239, which is much lower than the previous entries on this list, especially compared to R-410A, which it replaces. It offers excellent performance and cooling power, too.
- R-454C: R-454C features a low 145 GWP. It’s intended to replace R-404A rather than R-410A, but the changeover to the new gas should require minimal changes.
Why A2L Refrigerants Need Extra Care
Unlike R-410A, A2Ls present a flammability concern, which is why they’re not intended for direct R-410A replacement. System designs must take into account the possible dangers of A2L refrigerants.
To avoid ignition from electrical components, cooling systems must adhere to strict rules. These rules cover maximum allowable openings for relays to ensure refrigerants don’t reach flammable concentrations, as well as the separation of ignition sources.
Are A2Ls the Ultimate Solution?
A2Ls are less harmful to the environment than previous refrigerants, but that doesn’t mean they’re perfect. The world thought that HFCs were a great advancement 30 years ago until tests showed it was a formidable greenhouse gas. So A2Ls may be another stepping stone to finding an ecologically neutral refrigerant.
Looking for Alternatives to HFCs? Consult the Experts
Changing over to a new refrigerant is a major feat, one best handled by professionals. If you’re looking to lower your impact on the environment (and your energy costs), the Severn Group can provide you with an entirely new system running on low GWP refrigerants. Contact us today to set up a consultation.