What Changes Will You Soon See With the Shift to A2L Refrigerants?

This article was written by Don Gillis, the current Technical Training Manager at Chemours. Don was also involved in a popular symposium session about A2L refrigerants with Jason Obrzut and Dr. Chuck Allgood, which you can now watch for free on our YouTube channel HERE. Thanks, Don!

We all know that the change to A2L refrigerants is right around the corner. In fact, manufacturers will be required to have only A2L refrigerants in their residential and light commercial equipment by January 2025. 

What you may not know is that other countries have been working with A2L refrigerants for some time. Even in the United States, if you’ve bought a new car in the last 7 years, it probably has R-1234yf in it. In fact, 9 out of every 10 cars made today have A2L R-1234yf in it. If you’ve purchased a PTAC or window unit recently, it is also more than likely charged with R-32.

As a contractor, you may be wondering what the incoming changes mean for you. This article hopefully will give you a better understanding of what these changes might look like in your day-to-day life. We're going to walk through some of the things you can expect to see and some of the things that are proposed to be happening soon. 

A2L Refrigerant Tools

Let’s start with tools! First off, make sure that all the tools that you are purchasing are UL certified, like vacuum pumps, recovery machines, and electronic refrigerant leak detectors.

With that said, that doesn't mean last year's recovery machine that you just purchased is not A2L-qualified; you will need to check with the manufacturer of the equipment to make sure to see if there is a list of model numbers that your recovery machine falls under. This goes for all tools.

Disposable Cylinders 

Disposable refrigerant cylinders will be identified with a red band or a stripe. They're also going to have a different type of safety feature on them; instead of a rupture disc, this will be a relief valve. Unlike the rupture disc, this valve will only allow enough refrigerant to relieve the pressure. 

With that said, the relief valve will be too rigid for you to be able to puncture it or decommission the tank. You'll need to use a non-sparking tool and puncture the tank in the side right around the middle. 

Flammability and Safety Features

Unlike most of the equipment we use today, the new A2L equipment will have some built-in safety features. There will be sensors that can detect the A2L refrigerants if there is such a leak. You may also expect to see a pump-down solenoid valve that pushes the refrigerant out to the condenser, away from the building/structure, when a leak is detected. 

When working on A2L equipment, reaching a flammable concentration is the most critical concern. Always check for improper connections and be aware of confined spaces to be as safe as possible when working on A2L equipment. 

Regarding flammability, there’s a huge misconception that there’s propane in A2L refrigerants. I get this question all the time, and the answer is simply no, there is not. There are no hydrocarbons of any kind in A2L refrigerants

Now, with that said, I also want to mention that A2L refrigerants will not be allowed to be used in A1 systems. It's just not allowed. Don't try it. It's not worth the liability of you or your company—and obviously the safety of others. The safety devices used in A2L systems are there for a reason, and an A1 system will not have the same capabilities as an A2L system.

A2L Recovery Cylinders

Like the disposable cylinders, recovery cylinders will also be identified by a red band on them. You may have heard that these tanks will have left-handed threads to differentiate them from A1 recovery tanks; right now, it’s looking like A2L recovery tanks will indeed have left-handed threads. 

Many R-410A replacements will use the same pressures we use for R-410A today. 

Tank Storage on Trucks

Our service trucks, for the most part, will be business as usual. Right now, as it stands, the cylinders are going to be required to be upright, which is the best practice for A1 refrigerants and other containers like nitrogen tanks anyway. 

However, there has been testing on the A2L tanks to see if they can lay on their side in transport, and the testing has come out very positive so far; that could be approved soon, but we just don’t have the surefire answer right now.

Service Practices

We won’t need to expect drastic changes in service pressures as we did during the transition to R-410A from R-22. R-410A is actually a blend of A2L R-32 and flame suppressant R-125, so it’s no surprise that the operating pressures of R-32 and similar A2L blends will be pretty close to what we see now. 

You may have heard that many of the service practices for A2L systems are already best practices for A1 refrigerants. That is more or less true, but it’s not very specific. 

For the most part, you will be fine if you’ve been reading the HVAC School tech tips and using them to inform your practices. Overall, there are three main practices that were optional for systems with A1 refrigerants but will be required for systems that use A2Ls:

Purging the circuit with inert gas

You should purge the lines of an R-410A system with an inert gas like nitrogen. That’ll reduce the probability of contamination and the degradation of line sets that happens when oxides form. 

Even though you didn’t have to do it for R-410A systems, you will be required to do it for systems that use A2Ls. 

Evacuate the circuit

You’ve probably heard a lot about pulling a deep vacuum. Believe it or not, pulling a deep vacuum wasn’t necessary for systems with A1 refrigerants. It was still a good idea to evacuate the system to ensure that you had a clean, dry, and tight system, but it wasn’t required.

With the switch to A2L refrigerants, evacuation will be required to make sure our systems are free of anything that isn’t refrigerant or oil. Bryan made a video about proper evacuation a while ago, which you can watch HERE; even though the procedure was demonstrated on an A1 system, the practice will be fundamentally the same. 

Leak and pressure test

Since A2Ls are mildly flammable, refrigerant leaks are potentially more hazardous in A2L systems than in A1 systems. 

Checking for leaks and standing pressure tests are beneficial for many reasons, even with A1 refrigerants; after all, leaky systems that use A1s can lose charge over time and cause poor performance. 

However, standing pressure tests and leak checks will be even more important as we switch to equipment that uses A2Ls. 

Fake and Illegal Refrigerants

The industry often sees an uptick in the distribution of fake and illegal refrigerants during transitions. We saw some cases when we went from R-22 to R-410A, and we might see the same as we transition to lower-GWP refrigerants.

A fake refrigerant doesn’t match the label on the tank. In extreme cases, a tank labeled for a non-toxic or mildly flammable refrigerant may hold a highly toxic or flammable substance. The best way to protect yourself and your customers from these situations is to purchase refrigerant only from a supplier you trust. Some bad actors may go so far as to put the logos of well-known manufacturers onto illegitimate products, so be sure to stick with a supplier that you know receives refrigerant from trusted sources.

Since we are dealing with a phasedown rather than a phaseout, the issue of illegal refrigerant will likely be less of an issue. The manufacturing and importation of higher-GWP HFCs are gradually being reduced by 85%, not outlawed entirely. However, during the R-22 phaseout, we saw the introduction of illegal replacement R-22a, which was made up of several hydrocarbons.

Again, legitimate A2L refrigerants do not use hydrocarbons of any kind. Opteon has an infographic and video that breaks down the differences between A2L refrigerants and A3 hydrocarbons, which you can access by filling out a form HERE. Dr. Chuck Allgood from Chemours also has a webinar about illegal, fake, and counterfeit refrigerants, which you can watch HERE.


As A2Ls start becoming part of our everyday life, we’ll have to make sure our best practices become the norm and that we’re staying aware of the changes to tanks, tools, and more. 

That said, more information is bound to come out between now and 2025, which is when we can expect manufacturers to begin distributing equipment with A2L refrigerants. If you have any questions, you can email me at don.gillis@chemours.com. Thanks, everyone! 

—Don Gillis


shane w rasbury
shane w rasbury
6/3/23 at 02:17 AM

good information as an instructor for a college it is good to start students in the correct Method.

6/3/23 at 07:32 PM

Purging the circuit with inert gas
“Even though you didn’t have to do it for R-410A systems” why what are the reasons ???
Evacuate the circuit
“pulling a deep vacuum wasn’t necessary for systems with A1 refrigerants”
again, why what are the reasons, what about the hundreds of videos and articles were pushing and pushing for that procedures ???

why now you are telling this informations ???

    6/14/23 at 04:46 PM

    Hashim, those are good points. Flowing nitrogen and pulling a deep vacuum were best practices and SHOULD be required but now it’s going to be even MORE important and required with A2Ls.

Mac Ludin
Mac Ludin
6/22/23 at 10:45 PM

Let’s imagine a scenario where a customer decides to replace their furnace before the end of 2024 but opts to keep their old AC unit since it’s still functioning despite its age. However, a few years later, they find themselves in need of a new AC system. The question that arises is whether the existing furnace will be compatible with the new A2L AC or if they will have to install a new furnace designed for A2L safety.


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