Thoughts on Flammable 2, 2L, & 3 Refrigerants

Over the past few years the biggest concern when it came to refrigerants has been their Global Warming Potential. The higher the number the more damage that refrigerant could do to the environment. The Ozone problem has been fixed, more or less, due to the Montreal Protocol. In fact, just this month scientists announced that the Ozone hole is at the smallest it has ever been recorded. The problem today though is Global Warming or Climate Change. It seems that ALL of the popular HFC refrigerants used today have a GWP problem. Alternatives needed to be developed.

As we all know, there is no perfect refrigerant. There are always sacrifices that have to be made when selecting a refrigerant rather this be safety, environment, performance, or cost. Because of all of the press and news coverage that Climate Change has been receiving the world has been focused on reducing all of these refrigerants’ environmental impact. The smaller the GWP number the more friendly the refrigerant is to the environment.

Lower GWP means Higher Flammability

The problem here is that the alternatives on the marketplace today that have a lower GWP number also come with a higher flammability rating. The HFCs that we all know and love today are mostly all rated as a ‘1’ on ASHRAE’s flammability scale. These refrigerants show no sign of flame propagation when tested in air at 21° Celsius (69.8° Fahrenheit) and 101 KPA. (14.6488 pounds of force per square inch.) These refrigerants are also non-toxic and are rated as an A1 on ASHRAE’s scale. They are very safe to technicians and to end-users.

The alternative refrigerants that are now being used in place of R-410A, R-404A, R-134a, and other HFCs are NOT rated as a ‘Class 1’ on the flammability scale. Depending on the refrigerant you will most likely see them rated as a ‘Class 2’ or a ‘Class 2L.’ These refrigerants are slightly flammable, or have a lower flammability rating. In some cases HFC alternatives, like Hydrocarbons, are rated as a ‘Class 3’ on the flammability rating scale. These refrigerants are in the higher flammability risk zone, some examples of them are R-290 Propane and R-600a Isobutane.

While some of these replacement refrigerants have been around for decades, others are being developed in laboratories as we speak. Honeywell and Chemours both have their own newer product lines known as Solstice and Opteon. These lines mainly focus on HFO refrigerants but also have some HFC releases as well. In both instances though these new refrigerants are classified as lower flammability. Some examples of these are the ever-popular automotive application known as R-1234yf and then Honeywell’s R-452B (Solstice L41y.)

Adoption in the US

In the past the United States has been hesitant to use refrigerants with flammability risk. Safety was the priority for us. If the choice was between environmental harm or worker/end-user safety we seemed to choose safety most of the time. This isn’t as true for the rest of the world. Countries in eastern Asia have been working with hydrocarbons and other flammable refrigerants for decades without any major issues. But, there is a lot more training and precautions that have to be taken in order to work on a propane system correctly.

The question that I have in my head, and what caused me to write this article today, is that is the United States ready to adopt these flammable refrigerants? I’m not just talking about in vending machines or super market coolers folks. No, are we ready to accept flammable refrigerants in a traditional home or office split system? R-32 is looking to do just that. Over in Europe and Asia it has become one of the leading refrigerant for split system applications and is widely seen as the replacement for R-410A. R-32 is rated as 2L, so it is only slightly flammable, but the risk is still there.

Looking at the Environmental Protection Agency’s SNAP approved refrigerants list I do see R-32 on there as an approved refrigerant for home and office air conditioning. The catch is that it has to be “for use in self-contained room air conditioning; see rule for detailed conditions.” So, the applications are still limited for now, but that may change in the near future. Mini-split R-32s have become quite popular as well. I believe it’s only a matter of time before we start seeing R-32 in split systems.

I am curious, what my readers think of this. Do any of you see problems with flammable refrigerants? What are your thoughts on the refrigerant pendulum swinging away from safety and over to environmental? Will you feel comfortable working on systems with these types of refrigerants? I’m anxious to hear your thoughts on the matter as all I see on the topic are others who have written articles. Please feel free to e-mail me your thoughts!