In my last editorial, I suggested that contractors think about where we’ll be in 5 or more years and to stay informed about what’s going on in our industry. We will probably be facing another shift in refrigerants within 10 years in the U.S.
The question now is whether there will be two sets of lower ratings or one. If there are two and the first one is higher than 466, we’ll be OK since that’s the GWP of R-454b. R-32, with a GWP of 675, would be eliminated. Once the standard is set below 150, the viable options become propane/R-290 (GWP of 3), CO2/R-744 (GWP of 0) or some type of hydrofluoroolefin (HFO) refrigerant such as R-1234yf (GWP of 4 and already being used as a replacement for R-134a in many vehicles).
We may get a sense for where we’re headed by looking at standards set in the European Union (EU)*. In Europe, the new F-gas regulation entered into force on March 11, 2024.
For air conditioning and heat pump self-contained units with a capacity lower than 50 kW, the GWP limit is 150 from 2027, whereas all F-gases will be banned from 2032. This means that the commonly used R-410A, R-32, R-452B, R-454B will be banned already starting in 2027. The option that will most probably be used is propane/R-290, as self-contained units can be located outdoors, and this facilitates compliance with safety standards. However, other refrigerants with a GWP<150 will be allowed until 2032 unless they are banned by PFAS restrictions (for example R-1234ze GWP 7, R-1234yf GWP 4 and R-471A). Split units with a capacity lower than 12 kW will have a GWP limit of 150 from 2027 (air-water) and from 2029 (air-air), whereas the use of F-gases will be banned from 2035. R-1234yf, R-1234ze and R-471A are some of the options available until 2035, unless they are banned by PFAS restrictions. Split units with a capacity higher than 12 kW will have a GWP limit of 750 from 2029, thus R-32, R-452B and R-454B will be allowed. In 2033, the GWP limit will be 150. The options are the same as described for smaller units.
What properties differentiate propane/R-290, CO2/R-744 and HFOs?
As alluded to in the EU report, propane/R-290 is highly flammable. It requires strict safety precautions during installation, maintenance, and handling, and therefore more training. The positives are it has excellent thermodynamic properties that result in higher energy efficiency. It is versatile, capable of being used in both residential and commercial heat pump systems, including water heaters and industrial HVAC units. Heat pumps using R-290 can operate effectively in a wide range of temperatures, making them suitable for various climate conditions.
CO2/R-744 operates at very high pressure and requires stronger, more expensive components, increasing overall system costs. The high pressure also increases the likelihood of leaks and requires specific safety protocols and procedures. R-744 loses efficiency in warm climates. On the positive side, it can lead to higher COP values compared to traditional refrigerants, is a natural refrigerant, non-toxic, non-flammable and readily available.
Some HFOs can degrade into compounds which can be persistent in the environment and potentially harmful and some are classified as A2L, mildly flammable. However, they have emerged as a promising HFC alternative, offering comparable or improved performance in various applications compared to both legacy refrigerants and some natural refrigerants.
Watch the “R32 is NOT Going Away!” February 2025 A2L video featuring Clifton Beck of HVAC Excellence and Aaron Tevebaugh, Senior Director of Regional Operations at Johnstone Supply HERE.
*EU information from Carel.com “Worldwide refrigerant regulations: what are the options?” 5/9/24
My next editorial will explore how widely Propane/R-290, CO2/R-744 and HFOs are currently being used, who they are backed by and any legislation that may be under consideration to promote any of the refrigerants. Read it first in the coming weeks at ACprosite.com or in the next eLetter being sent in the middle of June.
Warm regards,
Peter Montana, Director, ACprosite.com
pmontana@ACprosite.com
813.417.6792
