There is no better indicator or barometer within the industry then the Carrier Corporation. After all, they are one of the biggest and most stable air conditioning manufacturers out there. They are one the ‘trend setters’ within the industry. When a business decision is made everyone watches, observes, and they may even imitate. The same can be said when they choose a new refrigerant.

That is exactly what happened. The Carrier Corporation along with Chemours announced today that Carrier would be transitioning their ducted residential and commercial air conditioning products away from R-410A and over to R-454B. This new refrigerant R-454B, also known as XL41, is an HFO refrigerant from Chemours under their Opteon brand name. The transition for Carrier is scheduled to begin by the year 2023. This is a big deal folks. This could very well be the beginning of the end for R-410A. Especially if other companies began to follow suit.

As most of you know there has been a battle going on for the past few years as to what refrigerant will be the golden choice to replace R-410A. It seems like Puron has only been around for a few years but now there are already companies and countries pushing it out and wanting a better more climate friendly alternative. As I write this article today there is still not one clear and defined winner. None of this isn’t for lack of trying though. There are all sorts of 410A alternatives out there, the problem is none of them were gaining significant traction. This news from the Carrier corporation adds fuel to the fire for R-454B. Along with Carrier some other prominent companies have announced their support for XL41 including Johnson Controls and York. With Carrier coming on board I wouldn’t be surprised if we begin to see more companies announce their support in the not too distant future.

The big distinction here and the reason companies are switching to XL41 is that it has a significantly lessened Global Warming Potential then the other alternatives out there. R-454B has a GWP of only four-hundred and sixty-seven. That is nearly eighty percent less GWP then R-410A and even thirty percent less then the proposed R-32 alternative. This very low GWP gives companies and manufacturers peace of mind knowing that they will meet future climate targets today if they make the switch. I would be apt to purchase one of these machines if I knew it was going to stand the test of time and not have to go through a phase down/phase out period.

The downside though with this newer HFO refrigerant is that ASHRAE has it rated as an A2L. The 2L is what may worry some of you, as that means that the refrigerant has lower flammability rating and a lower burning velocity. While some of you may already have experience working with lower or even mildly flammable refrigerants others may not. In reality though folks, flammable refrigerants are perfectly safe as long as you follow all of the proper precautions and safety procedures.


For more information on R-454B please click this link to be taken to our official fact and information sheet on the refrigerant. This sheet attempts to provide any and all information you would ever need on 454B. Rather it’s the GWP, the chemistry, what’s in the blend, the temperature glide, or anything else we aim to have it in our fact sheet. If while reading you find something that isn’t accurate or if you found that we missed something please do not hesitate to reach out to me and let me know. I want RefrigerantHQ to be a great resource for those of us in the industry and I can’t do that if I have mistakes up!

Thanks for reading,

Alec Johnson




Hello ladies and gentlemen and welcome to RefrigerantHQ. Today we will be taking an in-depth look at the newer HFO refrigerant from Chemours known as R-454B or XL41. This Opteon HFO refrigerant was created as an alternative to the ever commonly used R-410A Puron. While we have only been using 410A for around ten years or so there is already a push to phase down 410A usage and replace it with a refrigerant with much lesser Global Warming Potential.

One of the top contenders to replace R-410A is this new HFO refrigerant known as R-454B. In this article we’re going to take a look at all of the facts about this refrigerant and also share our thoughts about the refrigerant. If you see anything that is missing or if anything is inaccurate please reach out to me and I will correct as soon as possible.

The Facts

Name (2):XL41 (Opteon)
BrandOpteon (Chemours)
Chemistry:HFO Blend: R-32 (68.9%) & R-1234yf (31.1%)
Chemistry (2):Click Here for R-32 Fact Sheet
Chemistry (3):Click Here for R-1234yf Fact Sheet
Status:Active & Growing Market.
Future:Set to Replace R-410A Applications
Application:Residential & Commercial Air-Conditioning.
Application (2):Heat Pumps & Chillers
Replacement For:R-410A Puron
Retrofitting From R-410A?No, New Machines Only.
Why Can't I Retrofit?Due to 2L Flammability Rating.
Ozone Depletion Potential:0
Global Warming Potential:467 (78% Less Then R-410A)
Toxicity Levels:A (No Toxicity Identified.)
Flammability Levels:Class 2L - Lower Flammability
Lubricant Required:POE
Boiling Point (101.3 kpa):-50.9° Celsius or -59.62° Fahrenheit.
Temperature Glide1.5 K or -456.97 Fahrenheit
Critical Temperature:77.11 Celsius or 170.60° Fahrenheit
Liquid Density (21.1 °C)996.5 kg/m3 (62.2 lb/ft3)
Auto ignition Temperature:Unknown ( Couldn't Find)
Burning Velocity (23 °C)5.2 cm/s (2.0 in/s)
Molar Mass111.8
Molecular Weight62.6 g/mol
Manufacturing Facilities:United States (Texas)
Color:Colorless Liquid & Vapor
Odor:Slight, ether-like
EPA Certification Required:Yes, 608 certification required by January 1st, 2018.
Require Certification to Purchase?Yes, 608 certification required by January 1st, 2018.
Cylinder Color:Undefined by ASHRAE
Safety Data Sheet (SDS)Click here (Sourced from Climalife.co.uk)
Bulk Purchasing:CLICK FOR A QUOTE!

Thoughts on R-454B

R-454B, or XL41, was invented and designed by the Chemours company as an alternative to R-410A applications. These applications include your traditional home air conditioners, your commercial air conditioners, heat pumps, and the occasional chiller. XL41 is a blended HFO refrigerant is comprised of sixty-eight point nine percent R-32 and thirty-one point one percent R-1234yf.

One of the biggest attractions of R-454B is the savings in whats known as Global Warming Potential, or GWP. Every refrigerant out there rather it is a hundred years old or it was just invented yesterday has a GWP rating. GWP is a measurement on how potent a certain chemical is to the environment. The higher the GWP number the worse it is. Like with all scales, there needs to be a zeroing point. In this case the zero scale is Carbon Dioxide, or R-744. CO2 has a GWP number of one. As a comparison the commonly used R-410A refrigerant has a GWP of two-thousand and eighty-eight.

Looking at that number we can begin to see the problem with R-410A. It is directly contributing to Global Warming and Climate Change. The reason R-454B is being selected for newer applications is due to it’s much lower Global Warming Potential. 454B’s GWP is four-hundred and sixty-seven. That is nearly an eighty percent decrease when compared to Puron. This impressive number puts it at the lowest GWP alternative to R-410A. To give you some perspective, the other contender as an R-410A replacement, R-32, has a GWP of six-hundred and seventy-five. R-454B is an additional thirty percent lower. Along with that, 454B has a zero Ozone Depletion Potential rating so there is no risk there either. It is a very healthy refrigerant for the environment.

R-454B, or XL41, is classified as an HydroFluroOlefin refrigerant. These types of refrigerants, known as HFOs, are known for a few things. The first is that they have significantly lower Global Warming Potential then the commonly used HFC refrigerants of today. This fact right here checks a lot of boxes for business owners and manufacturers and may be enough to get them on board. However, like with any refrigerant, there is always a downside. HFO refrigerants are also known for their flammability. It seems we never can truly ‘win’ with refrigerants. There are always Pros and Cons.

In the case of R-454B it is rated by ASHRAE as an A2L. The A rating is great as it indicates that the refrigerant is not toxic. Other refrigerants with this same ratings are R-22, R-134a, and R-410A. The problem though lies in the 2L rating. This indicates a lower flammability rating for R-454B. Most of the common HFC refrigerants that we handle today are rated as a 1 by ASHRAE. A 1 rated refrigerant indicates that there is no risk of flame propagation. A 2 rated refrigerant has a lower flammability rating. Now, a 2L rated refrigerant means that along with the lower flammability we also have a lower burning velocity. This 2L sits R-454B right in the middle of the flammability refrigerant scale. While HFCs are rated as a 1 other very flammable refrigerants like Propane (R-290) are rated at a 3.

While a flammable refrigerant may sound intimidating and dangerous we should mention that they are perfectly safe and are used everyday throughout various Asian countries such as Japan and Korea. They do this daily and prevent accidents due to two major factors. The first is that they take the proper precautions when installing and handling flammable refrigerants. The second is routine maintenance. If you follow your training and ensure that everything is done by the book you’ll be fine.

Regardless though, the thought of working with flammable refrigerant deters a lot of technicians and contractors from using these newer HFO refrigerants. Lastly, since R-454B has an increased flammability rating then R-410A you are NOT able to retrofit existing 410A machines over to take R-454B. This is due to the specialized parts and components that a flammable refrigerant needs for it to work safely. If you wish to go with R-454B refrigerant you will need to purchase a whole new machine.

A few other notes worth sharing on R-454B:

  • XL41/454B is rated as five percent more efficient then R-410A Puron.
  • 454B offers the lowest GWP alternative to R-410A all without compromising on system performance.
  • While retrofitting isn’t possible, R-454B will not require major equipment modifications.


It is far too early to say rather or not R-454B will be the fabled R-410A killer or not. There are numerous alternatives out there that are all gaining traction. The question now though is will one of these began to gain speed over the others? Will companies around the globe began to pick one over the other? It may already be happening with R-454B. There are numerous articles and stories out there about companies moving away from R-410A and over to R-454B. Just a few of these companies are Carrier, York, and Johnson Controls. These are all huge names in the industry and may indicate a turning point.

But, as I said before folks, at this point it is still a guessing game. The true alternative for R-410A may have not even made it’s debut yet. Time will only tell.

Thanks for reading,

Alec Johnson