R422B Refrigerant Facts & Info Sheet

R422B is a hydrofluorocarbon refrigerant that comprises of three components. They include two hydrofluorocarbons, R-125, R-134A, and one hydrocarbon, R600A.

The refrigerant comes with a variety of features, benefits, and applications. One of the most notable functions is that 422B is a drop-in replacement for R22. What separates it/ or makes it stand out amongst the various drop-in replacements in the market is that it is compatible with mineral oil, Poly Olester, and PAG oils.

For technicians, this is good news. When repairing any system that uses R22, you don’t have to worry about changing the system components or even changing the oil. All you have to do is recover the R22 and charge the system with the 422B refrigerant. And the process is complete.

What other qualities does this refrigerant have? Is it even energy efficient? Well, we’d like to look at that in this article. We will discuss the physical properties of 422B, its applications, pros, and cons. Read further to learn more.

R422B Facts Table

Name - Scientific:1,1,1,2,2-Pentafluoroethane, 1,1,1,2-Tetrafluoroethane, Isobutane
Name (2):NU22B
Name (3):HFC422B
Chemistry:R125, R-134A, R600A
Status:Active & Growing
Future:Will be phased out for more eco-friendly options
System Type:low, medium, and high temperature systems
Application:Residential and commercial Air Conditioning Systems
Application (2):Industrial Refrigeration
Application (3):Non-flooded chillers
Application (4):Industrial Refrigeration
Replacement For:R-22 and R-417A
Ozone Depletion Potential:0
Global Warming Potential:2526
Global Warming Risk:Moderately High
Toxicity Levels:A (No Toxicity Identified.)
Flammability Levels:Not flammable at atmospheric pressure
Lubricant Required:Mineral Oil, POE, and PAG Oils
Boiling Point:−41.8 °C−42.4 °C (-43.2 °F- -44.32°F)
Critical Temperature:83.2 ?C or 181.8 ?F
Critical Pressure:574.1 psia
Temperature Glide:5
Molar Mass:108.5 kg/kmol
Melting Point:Not Available
Vapor Pressure:120.6 psia (20 ?C)
Manufacturers:Various Including: Honeywell, Chemours, Arkema, Mexichem, Chinese, etc.
Manufacturing Facilities:All Over Including: USA, Mexico, EU, China, and others.
Color:Colorless gas
EPA Certification Required:Yes
Require Certification to Purchase?Yes
Cylinder Color:Unknown



R422B PT Chart

After visually inspecting a HVAC system, locating the problem, and identifying the exact refrigerant used in that system, what do you do next? Yes, you got it right. You take the Pressure Temperature chart, otherwise known as the PT chart.

This sheet of paper/ document shows you the exact pressure a refrigerant will be at a particular temperature. You no longer have to do trial and error when charging the refrigerant, as this can increase your chances of damaging the entire system or vital components within it. In fact, if the system doesn’t respond as it should, after charging it, check the PT chart to correct the problem.

Additionally, the PT chart also gives you detailed information on the subcool, superheat, and the saturation point of that specific refrigerant. And remember, each refrigerant in the market has a particular PT chart that it uses. So, here’s one you can use with R422B.

R422B PT Chart


So, what are some of the ways you can use R422B?

Primarily, the refrigerant is a drop-in replacement of R22. The refrigerant (R22) had all the qualities to enhance system performance. However, the only problem was that it contained Chlorine since it was a HCFC refrigerant. Chlorine negatively affects the Ozone layer, which usually plays a role in protecting the earth from dangerous UV rays.

So, when governments started phasing R22 out of the market, manufacturers began the process of looking for viable replacements.

Now, with HFCs becoming a go-to option, manufacturers started using different HFC refrigerants to develop blends such as R422B and R407C. HFC blends can either be a drop-in or a retrofit. Most experts use these two terms interchangeably, but they are different.

For drop-in replacements, the only thing you do is remove the R22 and charge the new refrigerant without changing the lubricant or any system components. Retrofits, on the other hand, may require you to change the oil and various system components depending on the refrigerant’s requirements.

So, if you have an older system that uses R22, this blend would be a perfect replacement.

You can also use the refrigerant as an R417A replacement. The refrigerant is an HFC blend that contains similar components as 422B. That is R125, R134A, and R600A. 417A is also an R22 substitute but would be only ideal in small fixed air conditioning systems.

Apart from this, 422B is also valuable for various low, medium, and high-temperature applications. Hence, it makes it a suitable blend for residential and commercial air conditioning, industrial refrigeration, and non-flooded chillers.


So what benefits would you when using R422B? First, let’s talk about how much money and time you can save as a technician.

When charging the refrigerant into your system, it’s no longer a long process since you don’t need to change the lubricant oil, compressor, or anything else. Simply, take out the R22 and charge the 422B into the system. By the way, the refrigerant is compatible with mineral oil, POE, and alkylbenzene (because of the hydrocarbon component). If you are using mineral oil and you notice a problem in how the refrigerant flows, adding POE can reduce viscosity.

You also save money when diagnozing a HVAC system since you don’t have to buy any replacement components.

The other benefit of the refrigerant is that it’s not flammable. Although it contains R600A, a hydrocarbon, and is flammable, you don’t have to worry since the refrigerant is stable within atmospheric pressure.

Besides that, the refrigerant is non-toxic. It has an A1 designation by ASHRAE. On the other hand, avoid direct inhalation or contact as you handle the gas. Ensure that you wear protective gear.

Further, the refrigerant doesn’t destroy the ozone layer. It has an Ozone Depletion Potential of zero.


The refrigerant has several limitations. One of them is that you shouldn’t expect it to perform at the same level as R22. You might notice a drop in energy efficiency when you use it as a substitute, eventually causing your system to run for a longer time.

Another significant problem with the R422B is that it has a greenhouse effect. It has a global warming potential of 2526. Hence, the reason you require an EPA certification to purchase or handle the refrigerant. Note that from January 2024, you might not be able to buy the gas since governments are planning to phase out HFCs for good.


We’ve come to the end of the article, folks. I hope that, by now, you have all the information you need to use the refrigerant. Although we may never have the opportunity to use R422B from 2024, you can use it as a replacement for old R22 systems if you still have them.

However, a good point to note is that you should avoid mixing it with R22 when charging it into the HVAC system. Otherwise, you might attract hefty fines since it’s illegal.

Other Relevant Links