R-454B & R-410A Refrigerants: Are They The Same?

You have probably gone to classes, listened to podcast or read articles about the phase out of R-410A, and the replacement refrigerant R-454B that will be in a lot of new equipment. R-454B is not the only replacement refrigerant, as some manufactures will use other refrigerants in their equipment. In this article R410-A & R454-B will be the two refrigerants that will be compared.

Let’s look at what is in the make up of the two refrigerants. R-454B is a blend of 68.9% R-32 & 31.1% of R-1234yf. R-32 is used in small to large equipment that heat and cool. R-1234yf is used in some of the new cars being manufactured. R-410A is a blend of 50% R-32 & 50% R-125. R-125 is used in fire extinguishers, which helps reduce the flammability of the R-32 it is mixed with. Just because R-410A has a gas that helps reduce its flammability does not mean it can’t be ignited. Scientist have a procedure for testing the flammability of refrigerants. They use a glass flask of electrodes and they interduce air and the refrigerant into the flask. Once the refrigerant is ignited, it has to stay in a 90-degree V-shape marked on the flask. Then the refrigerant is classified as being flammable or not flammable. Class 1 is not flammable and Class 2 is flammable. But R-454B did not fall into the Class 2 flammable category. The flame spread was a lot slower and fell just outside of the 90-degree testing range, so a new class was developed for it and it is Class 2L (Lower Flammability). There are also letters that classify the toxicity of the refrigerant. A is for lower toxicity and B is for higher toxicity.  R-454B is an A2L lower flammability refrigerant and R-410A is an A1 Non-Flammable refrigerant.