R-744 Carbon Dioxide is one of the oldest refrigerants in the world. Its first usage can be traced all the way back to the nineteenth century. Before the popularity of CFC and HCFC refrigerants Carbon Dioxide was one of the most widely used refrigerants. Chances are if you went to a movie theatre in the 1920’s then you were experiencing an R-744 air conditioning system.

When R-12, R-22, and other HCFC/CFC refrigerants began to rise to prominence we began to see a large decline in R-744 usage. This was due to its extremely high operating pressures which caused numerous part failures. The newer artificial refrigerants were much easier to maintain. In today’s world, as we progress through the twenty-first century we have begun to see resurgence in R-744. This is due to the detrimental effects that CFC, HCFC, and HFC refrigerants have had on the environment. Carbon Dioxide on the other hand is climate neutral with zero Ozone Depletion and a Global Warming Potential of only one.

If you haven’t run into an R-744 system yet you soon will as its popularity grows with each passing year. In this article we’re going to take a deep dive and take a look at everything there is to know on R-744. If I miss something please let me know!

The Facts

Name - Scientific:Carbon Dioxide
Name (2):744
Name (3):CO2
Name (4)R744
Classification:Natural Refrigerant
Status:Active & Growing
Future:Will Be Used All Over World in Various Applications
System Type:SubCritical (Cascade) & TransCritical
Application:Vehicle Air Conditioning & Transport Refrigeration
Application (2):Commercial Refrigerators & Freezers
Application (3):Commercial Vending Machines & Plug-Ins
Application (4):Industrial Refrigeration
Application (5):Ice Rinks
Replacement For:R-22, R-134a, R-404A, and other HFCs
Ozone Depletion Potential:0
Global Warming Potential:1
Global Warming Risk:Very Low
Toxicity Levels:A (No Toxicity Identified.)
Flammability Levels:Class 1 - No Flame Propagation
Lubricant Required:POE & PAG Oils
Boiling Point:−78 °C (-108.4 °F; 195.15 K)
Critical Temperature:31.04 °C or 87.87 °F
Critical Pressure:7,380 kpa
Triple Point:4.2 bar (60.9 psi) and -56.6 °C (-69.8 °F)
Temperature Glide:None
Molar Mass:44.009 g·mol−1
Density (2):1101 kg/m3 (liquid at saturation −37°C)
Melting Point:−56.6 °C; −69.8 °F; 216.6 K
Vapor Pressure:5.73 MPa (20 °C)
Heat Capacity:37.135 J/K mol
Manufacturers:Various Including: Honeywell, Chemours, Arkema, Mexichem, Chinese, etc.
Manufacturing Facilities:All Over Including: USA, Mexico, EU, China, and others.
Color:Colorless gas
Odor:Low concentrations: none.
Odor(2):High concentrations: sharp; acidic
EPA Certification Required:No
Require Certification to Purchase?No
Cylinder Color:Unknown

R-744 Pressure Chart

Knowing the pressure and the temperatures associated to the machine you are working on is essential to being able to diagnose any possible issues. Without knowing the temperatures you are more or less walking blind. These pressure checks give you the facts so that you can move onto the next step of your diagnosis. Instead of pasting a large table of information here I will instead direct you to our specific R-744 refrigerant temperature page. This can be found by clicking here.

R-744 Applications

Let me first start out by saying that R-744 is a very unique refrigerant, more so then others.  R-744 is a natural refrigerant. But, unlike other natural refrigerants, there is not a safety concern. With hydrocarbons you have the flammability risk, with Ammonia you have the toxicity risk, but with CO2 the safety risk is minimal. Along with it being a safe natural refrigerant it also is very versatile. It is mainly used in a transcritical refrigeration system but it can also be used in subcritical systems when done through a cascade. On top of that R-744 can be used as a secondary fluid refrigeration system. (For more information on transcritical systems please click here to be taken to a recently written article on the topic.)

Between these different types of refrigeration there are a wide a range of applications such as vending machines, supermarket refrigerators/freezers, industrial refrigeration, refrigerated transport, automotive air conditioning, heat pumps, and even in sports arenas for ice rinks. In this section we are going to take a look at each of these applications:

Vending Machines

One of the first targets in the global HFC phase down was R-404A. As you know, 404A was used in a variety of applications including vending machines. In the early 2010’s there was a push from a variety of companies, including Coca-Cola, to switch their vending machines away from 404A and over to R-744 Carbon Dioxide. Now, as I write this article CO2 vending machines are found all over the United States. One of the initial struggles of these systems was finding qualified technicians as these vending machines operate as a transcritical system rather then subcritical. The good news is that as the years go by and the amount of these transcritical machines grow then the technicians will become more seasoned and experienced with working on these kinds of systems.

Supermarket Refrigerators/Freezers

The grocery store refrigerators and freezer market didn’t switch over as fast as vending machines but there is significant progress being made. While R-744 isn’t necessarily the preferred refrigerant to use in these applications there are some companies moving forward. Depending on the application supermarkets will either use a stand alone plug-in unit that is very similar to a vending machine or they will use one system that connects to all of the various refrigerators and freezers.

When it comes to using R-744 the type of application will determine if the unit will be a subcritical cascade or a transcritical system. If we look at a stand alone refrigerator/freezer then we would be dealing with a standard transcritical system. This would operate very similar to how vending machines do. On the other hand, if we look at some of the larger systems that are all connected then we would be looking at a cascade system. A cascade system uses two or more refrigerants. In the example of R-744 we would find R-744 on the low temperature side of the cycle. By having R-744 isolated to the low end of the system we can prevent the refrigerant from going past the critical point and keep it subcritical. The other refrigerant used for the high side of the system can vary. It could be Ammonia, Propane/Isobutane, or even an HFC or HFO refrigerant.

Industrial Refrigeration

The term industrial refrigeration can be quite vague and can encompass a variety of applications from chillers, to chilled warehouses, to heat extraction, and so much more. In the past, before R-22 was phased out it was one of the top refrigerants used in these larger scale operations. When R-22 was phased out some companies switched over to the HFC R-404A/R-134a only to find that these refrigerants were going to be phased out soon as well.

In Europe, in Canada, and in other countries R-717 or Ammonia is one of the top picks when it comes to industrial refrigeration such as meat packing plants. Ammonia is chosen as it is highly regarded as the most energy efficient refrigerant out there. The downside, of course, is that Ammonia is toxic and can also be slightly flammable. Whenever you see a story in the new stating that a plant had to be evacuated due to a refrigerant leak the chances are that it is Ammonia is quite high. There are many instances of this occurring here in the United States and in most cases everyone is fine. We just have to ensure that the proper precautions are followed.

While R-744 may not be as efficient as Ammonia it has another thing going for it. It’s not toxic. That being said though it appears that the use of R-744 plants and chillers is still quite rare. I spent some time looking around online trying to find stories on R-744 plant usage but wasn’t able to find anything. It seems that Ammonia still has a strong hold on the industry but as technologies change and as HFCs become completely phased out we may begin to see more active R-744 industrial applications. If you know of some active R-744 plant applications please reach out to me and let me know.

Refrigerated Transport

When I hear the words refrigerated transport I instantly think of trucking. That’s most likely because I came from the trucking industry. I remember going through pallets of R-404A for our carrier refrigerated trucks. In the case of R-744 though the refrigerated transport we are discussing is naval transport or refrigerated shipping containers. It’s not just produce or meat being refrigerated on cargo ships though. No, in some cases cruise liners have installed CO2 systems to cool their larger refrigerators and freezers. Again, I looked around for any mention of R-744 being used in refrigerated cargo transport on trucks but saw no mention of it. This may still be down the road.

Automotive Air Conditioning

This one is definitely unique. If we rewind about ten years ago there were two refrigerants to choose from for automotive air conditioning. The first was the ever popular HFC R-134a. I am sure most of you are familiar with this refrigerant. You can buy cans of it at your local O’Reillys. At this time though a new refrigerant was introduced to the automotive sector. This refrigerant known as R-1234yf, was an HFO refrigerant invented between a partnership of DuPont and Honeywell. YF was to be the refrigerant of the future. It would replace R-134a and it would be used in every car from now on.

Most of the world was on board except for Germany. The German automakers had tested with YF and found that it was flammable. In one instance during a simulated collision the lines ruptured and spilled the refrigerant onto the hot engine block. The refrigerant ignited and caused a fire. This one test scared the German automakers, especially Daimler, away from using YF. While the rest of the world pushed forward with YF Daimler set off on their own to create the first automotive R-744 application.

Years later they achieved their goals and we now have German made cars using CO2 as their refrigerant. There is now no risk of flammability with their cars and they are still being environmentally friendly. I love hearing this story again and again as it’s a prime example of forging your own way and still coming out on top.

Heat Pumps

Japan has put forth a lot of focus on R-744 heat pumps. CO2 heat pumps can produce a much higher temperature output then a traditional HFC heat pump system. This is thanks in part due to the transcritical process. These heat pumps can heat water all the way up to one-hundred and ninety-four degrees Fahrenheit. (Source) The adaption of CO2 based heat pumps is moving forward, but it has been slowed due to the extremely high operating pressures and the breakage of components. (The same story we have seen in other CO2 applications.) In the future we will most likely begin to see CO2 heat pumps in mini-split air conditioner systems. Perhaps, down the road, we may even see them in traditional split air conditioning systems.

Ice Rinks

From my experience a typical ice rink uses either Ammonia, R-22, or an HFC such as R-134a or R-404A. What refrigerant is used seems to depend on what country you are in. Outside of America the standard refrigerant has been Ammonia. As we discussed earlier in this article Ammonia is widely seen as the most efficient refrigerant. When dealing with such a large application like an ice rink efficiency is a must. The downside of course, is the toxicity. The toxicity is especially important when it comes to a public area like ice rinks. It’s not just technicians or employees who are at risk but you also have the general public.

Here in America we are always hesitant to use the more ‘dangerous’ refrigerants such as Ammonia or Hydrocarbons. Because of this hesitation we instead went the route of R-22 for our ice rinks and hockey arenas. Now though, with R-22’s phase out coming to a close in 2020 ice rink owners are looking for alternative refrigerants. Sure, there are HFC and now even HFO alternatives that can be used in these applications but each of these alternatives still have a higher then neutral Global Warming Potential (GWP). The problem with these refrigerants is that they will not stand the test of time when it comes to climate impact and phase outs.

If I was an arena owner or manager I would only seriously be considering two options. The first is Ammonia like I discussed earlier. This comes with it’s own risks but you get the low cost and energy savings. The alternative is R-744 Carbon Dioxide. R-744 has it’s own Pros and Cons which I’ll get into in our next section, but the big selling point is that you get a climate neutral refrigerant that is safe to the public in case a leak occurs. While R-744 systems aren’t widely found in the world today, they are growing. An article I was reading from 2016 had this quote, ”

“Today the number of CO2 ice rinks is growing rapidly. There are now 25-30 CO2 ice rinks in the world,” he says. 20-25 of these CO2 ice rinks are in North America, 20 of which are in Canada (mostly in Quebec) and three in Alaska, according to EKA.” – Source

R-744 Pros & Cons

As we all know, there is no perfect refrigerant. Each one has its own individual upsides and downsides. It could have a great efficiency but also end up being very flammable. Or, it could be non-flammable and non-toxic but have very high Global Warming Potential. The point I’m making here is that there isn’t a perfect one out there and there may never be. In this section we’re going to take a brief look at the various Pros and Cons of using R-744 as a refrigerant. I pulled this information from all over the web, but one site in particular stuck out to me. This article from Emerson has an entire page dedicated to R-744 Pros and Cons. It can be found by clicking here and then scrolling to page twelve.

Let’s take a look at the Pros and Cons of R-744:


  • R-744 is seen as the ‘perfect’ natural refrigerant as it is climate neutral and there is not a flammability or toxicity risk.  It is rated as an A1 from ASHRAE. While it is non-toxic there is still risk if a leak occurs in an enclosed area as R-744 will displace the oxygen in the room and could cause asphyxiation. It is always best to have a leak detector with you so that you can detect the problem early before anything major occurs.
  • Overall, R-744 is more energy efficient and has better heat exchange then a standard HFC based system. While it may not be as efficient as Ammonia this gap between the two refrigerants is shrunk as the evaporator temperature drops. Carbon Dioxide also has a low compression pressure ratio which can improve volumetric efficiency. In some cases CO2’s volumetric efficiency is four to twelve times better then Ammonia. (Source – under Pressure & Temperature.)
  • I mentioned this earlier, but the biggest selling point of R-744 is that it is climate neutral. It has no Ozone Depletion Potential and it’s Global Warming Potential is one. In fact, R-744 is the zero basis for the whole GWP scale. This is a huge Pro as if there is one thing that business owners are looking for it is stability and consistency. R-744 is never going away due to it being so climate friendly.
  • One Pro to R-744 operating at such a high pressure and being such a dense gas is that the overall size of the parts and components is smaller and the overall charge required for a refrigerant cycle is lessened. In some cases the compressor can be up to ten times smaller than an ammonia compressor. As far as refrigerant charges, one example I read from manufacturing.net stated that to cool a two-hundred thousand square foot warehouse you would need forty-thousand pounds of Ammonia but with CO2 you would need less than seven-thousand pounds.
  • Carbon Dioxide is readily available and the price for this refrigerant is much less then HFC refrigerants that we see today. This is a welcome relief from the instability of prices on HFCs and HCFC refrigerants that we all know about.


While R-744 is the ‘perfect’ natural refrigerant in theory there are a lot of downsides.

  • The biggest one is for Carbon Dioxide to be used as a refrigerant it has to run under extremely high pressure. As an example, R-744 operates at ten times higher pressure then R-134a. Because of this extremely high pressure everything has to be custom built for an R-744 system so that it can withstand the high operating pressure. This includes the pipes, components, and everything else that goes along with the machine. If lesser components are used then you pose risk of constant failure due to the pressure.
  • If you wish to use R-744 as a stand alone refrigerant not in a cascade system then you will have to be running it as what’s known as a transcritical system. This is because R-744’s critical temperature point is only eighty-eight degrees Fahrenheit. There are many cases where the ambient temperature could be between eighty to one-hundred degrees. If your critical point for R-744 is only at eighty-eight degrees then how can you expect to remove the heat? (You can read more on the topic of transcritical refrigeration by clicking here.)
  • Suffice to say, a transcritical system and a high operating pressure system means two things.
    • The first is that there is increased expense for these systems. Not only do you have to pay for high pressure rated materials and parts but you also have to pay for a transcritical system. This setup is different then your standard subcritical system. The good news here is that with each year that passes technology improves and the cost of these higher pressure parts goes down.
    • The second is the increased complexity. The higher the complexity means less available qualified technicians. It may be a struggle to find qualified R-744 technicians, at least here in the United States. Each year though this is getting better as more and more businesses are adopting R-744 systems.
  • I mentioned efficiency in our Pros section earlier. The reason I mention it again is that the efficiency of R-744 is highly dependent on the type of system it’s being used in and the surrounding climate. I mean, think about it for a moment. We could have a subcritical cascade system for a supermarket in Miami. Or, we could have a transcritical ice rink in British Columbia. In each example we’re using R-744 but we now have two entirely different systems as well as two entirely different climates. Because of these variety of systems and applications it is difficult to measure one single efficiency measurement.

R-744 Past/Future


I am a big fan of history and can never get enough of reading historical books or watching documentaries. If you don’t understand the past then how can you understand the present or even the future? While refrigerant history might not be as interesting as other historical topics it is still good to understand it. R-744 can be traced back all the way back to the nineteenth century. In fact it was one of the very first refrigerants to ever be developed and used across the world. Experiments in refrigeration began in the late seventeen-hundreds and began to pick up speed in the eighteen-hundreds. It was in 1850 that Carbon Dioxide was first proposed as a refrigerant by Alexander Twinning. In 1869 one of the very first ice machines invented used Carbon Dioxide. Then in 1897 the first Carbon Dioxide refrigerator was introduced. More and more inventions and innovations followed.

In the late 1800’s and the early 1900’s there were a few mainstream refrigerants that we saw. These were your natural and hydrocarbon refrigerants such as Ammonia, Propane, Isobutane, and Carbon Dioxide. At this time Carbon Dioxide was found in all kinds of applications ranging from display cabinets, cold storage areas, market places, home/commercial kitchens, movie theaters, hospitals, trains, and even on cargo transport ships. The other natural refrigerants weren’t used as widely as Carbon Dioxide due to their safety concerns.

It seemed that R-744 was going to reign supreme as the main refrigerant in the world. This held true until the 1930’s. It was then that a partnership was formed between General Motors and DuPont. This partnership was made with one goal in mind: To create a cheap, safety, and reliable refrigerant. While Carbon Dioxide was safe it had it’s own problems. Just like we mentioned in our Pros and Cons section R-744 systems had numerous failures due to the extreme pressure that they operated under. The technology just wasn’t there to prevent these failures either so these air conditioners and refrigerators would bey very expensive to maintain.

After some time the General Motors & DuPont partnership came out with a new artificial class of refrigerants known as CFCs and HCFCs. Some of the refrigerants in this new classification were R-12 and R-22. These new refrigerants checked all of the boxes. They were safe. They were cheap. They were reliable. There was no more constant failure due to high operating pressures. At first, the adoption of these refrigerants was slow but that was only because of the manufacturing speed of the product. It was in the 1950’s that an innovation was done that greatly increased the speed of manufacturing CFC and HCFC refrigerants.

Once the supply could be met the demand skyrocketed. It wasn’t long until CFC and HCFC refrigerants were found all over the world in various applications. They could be your home air conditioner, your automobile, your refrigerator, or your local grocery store. They were everywhere. In the 1960’s there were a few more CFC/HCFC refrigerants invented, including R-502, that led to even more explosive growth.

With the growth and dominance of these new refrigerants it seemed that R-744 had taken a backseat. It was cast aside when the newer refrigerants came to market due to the high pressure that it operated at. There was no reason to use this expensive refrigerant anymore due to the mass production and reliability of R-12, R-22, and R-502. At least for a while, R-744 had reached it’s peak. It was in the 1980’s that things began to change.

The Ozone

It was in the 1980’s that a problem was discovered. Two American scientists, Mario Molina and Shepwood Rowland, from a California university were the first to notice Chlorine’s effect on the atmosphere. (Remember now folks, all of these CFCs and HCFCs contain Chlorine.)

These two scientists found that when a CFC refrigerant was exposed to ultra-violet irradiation that the Chlorine atom would detach itself from the CFC molecules. The remaining residue is oxidized resulting in the creation of a Chlorine oxidized molecule and a new residue. The Chlorine atom and Chlorine oxidized molecule move their way up to the stratosphere. Within the stratosphere there is a layer called the Ozone layer. This Ozone layer protects the Earth from ultra-violet rays and irradiation. What these scientists found out is that all of this Chlorine from CFC and HCFC refrigerants was working it’s way to the stratosphere. When it reached the stratosphere the Chlorine began to attack and weaken the Ozone layer.

Over decades of using CFCs and HCFC refrierants Chlorine began to accumulate in the stratosphere and overtime a hole began to form in the Ozone layer. Now, I say hole but this wasn’t a hole per-say. Instead, there was a weakening of strength in the layer. So, while there was not a hole the thickness of the Ozone was decreasing and decreasing rapidly thanks to the CFC and HCFC refrigerants.

The Ozone prevents harmful UVB wavelengths of ultra-violet light from passing through the Earth’s atmosphere. Without it, or with a weakened version of it, a variety of bad things could happen. Some of these include a much higher increased chance of Skin Cancer, more severe sunburns, more chances of cataracts, and a whole host of other problems.

After discovering the weakening of the Ozone layer nations banded together in what is seen as one of the greatest and most effective treaty’s every made. In 1986-1987 the Montreal Protocol was created and signed by over one-hundred nations across the world. This Protocol was an international treaty designed to protect the Ozone layer and to completely phase out the chemicals responsible for the weakening of the Ozone. The treaty went into effect in 1989.

Soon after that date marked the beginning of the end for CFC and HCFC refrigerants across the globe. The industrialized countries, like America, began to phase out the refrigerants first. R-12 was phased out in the early 1990’s along with all of the rest of the CFC refrigerants. The HCFC refrigerants such as R-22 or even R-502 were given a bit more time. Heck, R-22’s true phase out didn’t even begin until 2010.

Out with the old and in with the new, so they say. The refrigerants that were proposed to replace CFCs and HCFCs were known as HFCs, or Hydroflurocarbons. These refrigerants contained no Chlorine so there was no chance of them hurting the Ozone layer. Some of these refrigerants include popular refrigerants today known as R-134a, R-404A, and R-410A. But, now these refrigerants are under fire for their increase to Global Warming.

R-744 Present & Future

As I mentioned above HFCs were seen as the world’s savior from the Ozone depleting refrigerants. But, HFCs had their own problem. Instead of the Ozone this time it was Global Warming. These HFC refrigerants such as R-134a, R-404A, R-410A are known as ‘Super Pollutants,’ or ‘Greenhouse Gases.’ In order to measure their impact on the environment each of these refrigerants were given a Global Warming Potential number. The higher the number the more damage the refrigerant causes to the world. As a zero based scale for this measurement our old friend R-744 was used. Carbon Dioxide has a GWP of one. In comparison, R-404A has a GWP of three-thousand nine-hundred and twenty-two. Obviously, there is a large difference here.

I’m writing this article in 2019 and over the past ten years or so there has been a worldwide push to phase down and in some cases phase out HFC refrigerants completely. In order to phase out HFC refrigerants we have to have a replacement refrigerant. In some cases companies and countries have turned to a new classification of refrigerants known as HFOs. These HFO refrigerants are again synthetic products created by Honeywell & Chemours (Formerly DuPont). The problem with HFOs though is that they still have Global Warming Potential. Yes, not as high as HFCs… but the numbers are still there. Along with the GWP risk they also have a slight flammability risk. To me, I do not see HFOs being sustainable. I imagine the world will decide to phase them out in another ten or twenty years.

So, what is the solution you may ask? It’s R-744! Well, R-744 and other natural refrigerants. Technology has changed significantly since the last time R-744 was used widely. It’s been almost one-hundred years since we saw the mainstream use of Carbon Dioxide and now with nearly a century behind us the technology has significantly reduced the chance of component failures due to high operating pressures. We are now able to create efficient and stable R-744 systems without a large risk of failure.

While the cost of implementing R-744 systems is still quite higher then a traditional HFC system the costs have been coming down. This holds especially true in recent years as the push to innovate R-744 systems increases substantially with the phasing down of HFCs. While we are not there yet the costs are quickly shrinking the gap between HFCs and R-744.

There are many companies pushing forward with R-744 systems. Most of these are on smaller systems such as vending machines, but we all need to take baby steps. One company in particular, Coca-Cola, has installed hundreds of CO2 vending machines across the country. Along with Coca-Cola there are other grocery store chains out there using cascade R-744 systems mixed with other refrigerants such as Ammonia or lower GWP HFCs. We are even beginning to see R-744 uses in automobiles with the innovations that Daimler has made. As we completely phase down HFCs over the next ten years we will see more and more usage of R-744. It’s time has come again!


Well folks, after all of that I feel like we have covered our bases when it comes to R-744.  If you only take a few things away from this article let them be this. First, R-744 is a growing market across the world and you will begin to see more applications. It doesn’t matter what section of the industry you specialize in. R-744 is so adaptable that it’s only a matter of time before you come across it.

Secondly, since R-744 has no Ozone Depletion Potential and a Global Warming Potential of only one you can be safe in assuming that Carbon Dioxide will never be phased down our across the world. It is a natural refrigerant that has been used for over one-hundred years and it will continue to be used for another one-hundred years or more.

If you find that you’re still looking for more on R-744 then please check out our sources section below. This is where we pulled most of our data from and in some cases these websites can have a ton of information.

Thanks for reading,

Alec Johnson



RefrigerantHQ's Pressure Charts

Regardless of what system you are working on rather it is a home air conditioner, a vehicle’s air conditioner, a supermarket refrigeration system, or a large scale industrial application they all have one thing in common: Pressure.

Yes, as we all know one of the very first steps when it comes to diagnosing a refrigeration or air conditioning system is determining the various pressures that the system is operating at. Besides a simple visual inspection knowing the operating pressures of the machine is crucial. Having these facts along with the saturation point, the subcool, and the superheat  numbers for the refrigerant you are working on are essential when it comes to really understanding what is going wrong with your system.

After a visual inspection the very next step for the most seasoned technicians is pulling out their gauges and checking the pressure and temperature. It just becomes second nature after enough calls. I have heard stories of rookie techs calling some of the pros on their team for help on a system that they’re stuck on. It doesn’t matter what the situation is. It doesn’t matter if you’re in Miami or in Fargo. It will never fail that one of the first questions the pros ask the rookie is what your subcool is and what is your superheat? Having and understanding these numbers is instrumental to figuring out what to do next.

But, these numbers won’t do you any good if you don’t know what refrigerant you are dealing with and what the refrigerant’s boiling point is at each pressure level. This article aims at providing you with just that information.

R-744 Carbon Dioxide Pressure Chart

For those of us here in the United States coming across an R-744 Carbon Dioxide application may still be a rare occurrence. But, the world is changing and the popularity of this natural refrigerant is increasing. Along with the popularity the vast array of applications is increasing as well. You can find R-744 being used in vending machines, automobiles, supermarkets, and even in ice-skating rinks. The sheer versatility of R-744 and its climate friendliness is the reason we have seen such growth in its uses.

While we had mentioned earlier the concept of ‘subcool,’ it is important to note that in most cases R-744 applications do not have a subcool. This is because most R-744 systems operate as a transcritical system. Most refrigeration/air conditioning systems operate in what’s known as a subcritical process. This is your standard process that we are all used to. The difference with a R-744 application is that its operating temperatures can exceed the critical point temperature.  Carbon Dioxide’s critical temperature is just under eighty-eight degrees Fahrenheit. That eighty-eight degrees mark can easily be at or below the ambient temperature and when this occurs is when a transcritical system is required.

For more information on transcritical systems you can click here to be taken to our overview. The pressure and temperatures for R-744 can be found below:



There you have it folks. I hope this article was helpful and if you find that something is inaccurate here in my chart please do not hesitate to reach out to me. I have sourced this the best I could but there is always going to be conflicting data.  I’ve seen it multiple times on various refrigerants. I’ll search for a refrigerant’s pressure chart and get various results all showing different pounds per square inch temperatures.

The aim with this article is to give you accurate information so again, if you see anything incorrect please let me know by contacting me here. On top of this post we are also working on a comprehensive refrigerant pressure/temperature listing. The goal is to have every refrigerant out there listed with a pressure/temperature chart that is easily available.

Thanks for reading,

Alec Johnson



A Look

A few weeks ago I did an article on transcritical refrigeration. In that article I stated that I knew very little on the subject, but as I wrote the article I was able to teach myself a bit about it and understand the principles behind the transcritical system.

Well today we are going to be doing the same type of post except this time on cascade refrigeration systems. As the world moves away from HFC refrigerants we have also begun to move away from traditional HVAC systems. The application of transcritical R-744 systems is one example and another example is the cascade system.

As most of you know each refrigerant has its upsides and downsides. Along with climate friendliness, flammability, and toxicity, there are also refrigerants that are better for lower temperature applications and there are some better at higher and medium temperature applications. A cascade system takes advantage of this by using two different refrigerants, one for high side and one for low side. (In some more complicated cases there can be more than two refrigerants used.)

These two refrigerants operate independently and each have their own boiling points. The refrigerants run through their own cycles and then are joined together by the heat exchanger. At the heat exchanger the high/medium temperature refrigerant is used to cool the condenser of the lower temperature refrigerant. Another way to look at it is the condenser for the lower temperature system acts like the evaporator of the higher temperature refrigerant. In fact, the condenser in the lower temperature side is coupled to the evaporator on the higher side. So the evaporator on the higher side removes the heat released by the condenser in the lower cycle. The website hvacrschool.com provided a great diagram on the flow which can be found by clicking here.

Cascade systems exist when we are working with two large temperature differences. Say for example, the ambient temperature is seventy-degrees but you need a desired temperature of negative fifty degrees. (Cascade systems are used a lot in laboratories and research institutes.) Now, with a normal system this extreme temperature difference would not be achievable. This is where the cascade system comes in handy as you are able to bridge the temperature difference when you have two different refrigerants. Using this method certain cascade systems can achieve temperatures as low as negative two-hundred degrees Fahrenheit.

The advantages of cascade systems are twofold. First, as we mentioned above, cascade systems can achieve drastically low temperatures that traditional refrigerant circuit systems just can’t reach. Along with the cold temperatures cascade systems can be more energy efficient than the standard systems. This is done by choosing the most efficient refrigerant for both high side and low side applications. This allows for maximum efficiency and a savings on operating costs per month.

The downsides to a cascade system are rather obvious. First, they can be more expensive to build then a traditional system. This may come into play if the business owner is looking to install a cascade system in their place of business. (An example of this will be in our next section.) The other downside is that while cascade systems still pretty much follow the traditional refrigerant circuit they can be a bit more complicated to diagnose then your standard system.

Future Use of Cascade Systems

While cascade systems were mainly used for lab work in the past we are beginning to see a growth of these applications in less traditional areas. An example of this is seeing a cascade system installed in a supermarket freezer/refrigerator section. Back in 2016 Whole Foods installed a cascade refrigeration system for their new Santa Clara, California store. This cascade system is comprised of propane (R-290) and Carbon Dioxide (R-744).

The system contains nearly three-hundred pounds of propane charge, BUT, the propane never leaves the roof of the building due to it being a cascade system. Inside the building the harmless and non-flammable CO2 is used (Seventeen-hundred pounds of CO2 used).

This system is a prime example of using a cascade system in place of a climate damaging HFC system such as R-404A or R-134a. With this cascade system, Whole Foods was able to use switch their entire store over to natural refrigerants while still remaining efficient and keeping their customers safe and secure. There are also instances where a split system of Ammonia (R-717) has been used.

This investment was a great way for Whole Foods to future proof their refrigeration system. Neither one of these refrigerants are going to be phased out as they have no impact on the climate rather it be through Ozone Depletion or Global Warming Potential. R-744 and R-290 will be around forever. While yes, the downside may have been a heavier investment then a traditional system, Whole Foods can sleep easy knowing that their system will be in compliance for decades to come.


As HFC refrigerants begin to see further decline across the country we will begin to see more and more cascade systems applied. The good news is that if you understand the basic refrigeration circuit then you’ll find that a diagnosing a cascade system isn’t much different.

To learn more about cascade systems I recommend you visit the source articles that I have linked below. This is where I got my information from. I also specifically recommend the articles from RSES.org. While these articles are older they still provide a wealth of information on cascade systems and how they work.

Lastly, if you see anything that appears to be inaccurate or if I forgot something key on cascade refrigeration please reach out and let me know and I will correct as soon as I can.

Thanks for reading,

Alec Johnson




The other day I was trying to find a comprehensive listing of which cars were using the newer R-1234yf HFO refrigerant. Over in Europe YF refrigerant is now the standard for all new vehicles. (In some cases R-744 is used as well.) R-134a is no longer used due to its high Global Warming Potential.

A few years back the Environmental Protection Agency issued a new SNAP Rule known as ‘Rule 20.’ This new rule stated that a lot of the most popular HFC refrigerants would no longer be acceptable in new applications. One of the refrigerants and applications listed was R-134a for all 2021 vehicle model years.  This all but dictated that automakers would have to use 1234yf in all of their new vehicles.

Well, as you all know, Rule 20 by the EPA was overturned by Federal Courts. The EPA had overreached their authority and had their proposed rules thrown back in their face. Having this rule thrown out left the future of R-134a uncertain. We all knew that 134a wasn’t going to be around forever. It did have a high GWP and it did need to go… but now there was no government mandate to do so.

Most everyone thought as the years passed by auto manufacturers would begin to switch to 1234yf without a government mandate. After all, it was the cleaner option and other states such as California and New York have begun to phase down HFC refrigerants.  It only made sense to protect yourself and make the switch over now.

Top Selling Cars in 2019

All that being said I was curious exactly what automakers and models of cars are now taking the HFO 1234yf refrigerant. How many of them are still holding onto the past? Since I couldn’t find an exact list I took a different approach.

I googled for a listing of the top selling cars of 2019. What I found was a listing of two-hundred cars from a website called ‘goodcarbadcar.net.’ The listing had sales volume, dollars, etc. I was only interested in the ranking though. What was the number one car sold, number two, etc.

Now that I had my listing I cut it down to the top fifty and then begin going to work. My goal here was to find out what refrigerant each of these 2019 model year cars were using.  Some of these were harder to find than others. In most cases I googled the year, make, model, and ‘owner’s manual.’ Usually I could find the manual and then find the refrigerant type in there.

In other cases I found the manual but the manufacturer kept the type of refrigerant a secret. In fact nearly anything to do with the air conditioning system was kept secret. The most I could find was to either ‘Check Under The Hood,’ for the refrigerant type, or to contact your dealer for maintenance questions. In these circumstances I Googled around a bit more and did my best to fill in the blanks.

The completed table can be found below. Overall, I couldn’t find the refrigerant type for eight vehicles. (If you know what they are please reach out to me and I will update the table.) But, for the others that I did find it painted a pretty clear picture of the refrigerant market today for new vehicles.

Let’s look at the facts first. For the top fifty selling cars in the United States only fifteen of them are still using R-134a. The other twenty-seven are using R-1234yf. Even if we give the missing ten cars the benefit of the doubt and state that they are all using R-134a we are still looking at over fifty percent market share of R-1234yf within the United States. Some folks will say as high as sixty or even seventy percent market share.

Even if it’s just fifty percent that is still a HUGE number and it is only going to continue to grow. Each year more and more auto manufacturers make the switch to 1234yf. You may have noticed that in the table some Makes have a mixture of R-134a and R-1234yf. This is most likely them testing the waters with YF. They want to see if everything works as it should before they go all in on YF.

2DodgeRam PickupR-1234yf
15JeepGrand CherokeeR-134a
28DodgeGrand CaravanR-134a
38HyundaiSanta FeR-134a


This table provides us with concrete evidence that R-1234yf is taking over the automotive market. If you haven’t come across it yet then I can assure that you will soon. From what I have read the average age of a vehicle that needs an air conditioner repair is between five to six years. So, at that fifty percent market share that we have today we could be looking at half of all vehicle AC repairs being done on YF systems by the year 2025.

R-134a is going the way of R-12. In another ten or fifteen years it’s going to be rare to find an 134a vehicle and when your vehicle does take R-134a you may have to pay a pretty penny to get a recharge. (Just look at how expensive R-12 is nowadays.) The only good news here folks is that there isn’t a mandatory phase out of R-134a yet… so the prices will still stay quite low for the foreseeable future.

The big problem that a lot of end users have with 1234yf is not that it’s a new refrigerant. No, the problem is the cost.  The cost of a pound of R-134a can hover between two to four dollars per pound. The cost of R-1234yf can hover between sixty to seventy dollars per pound. That’s nearly fifteen times more than the cost of R-134a. You can see an example of this cost from our Ebay partner by clicking here.

Because of this huge cost increase there has been a rash of end users manually converting their YF systems back over to R-134a. Hell, there is even an adapter out there for it… Rather these folks like it or not R-1234yf is here to stay and with each passing year the amount of vehicles using it is growing.

For more information on R-1234yf check out our ‘R-1234yf Refrigerant Fact Sheet,’ by clicking here.

Thanks for reading,

Alec Johnson



Flammable Refrigerants

Last month I wrote on the International Electrotechnical Commission (IEC) and their decision on rather or not to increase the allowed charge limit on hydrocarbon refrigerant applications. Before their decision was made the maximum approved amount was one-hundred and fifty grams under the IEC 60335-2-8 global standard. This proposed increase would have moved the one-hundred and fifty grams limit up to five-hundred grams.

In April the IEC voted against the charge increase amendment. The decision was lost by one no vote. This ruling caused great disappointment across the industry. Many companies and organizations have been pushing to increase charge limits on flammable hydrocarbon refrigerants. The increased charge limit would allow hydrocarbons to be used in larger variety of applications.

Hydrocarbons are one of the top contenders for future refrigerants as the world begins to phase down HFC refrigerants such as R-134a, R-404A, and R-410A due to their high Global Warming Potential. While hydrocarbons can be dangerous due to their flammability they are also one of the most environmentally friendly refrigerants out there as they have no Ozone Depletion Potential and have very little Global Warming Potential.

There is a fine line that has to be walked though as if the charge limit on a propane or isobutane system is too high then the risk of catastrophic failure becomes higher.

This Week’s Recount

It was announced this week by the IEC that a recount was done on last month’s vote. It was found that Malaysia’s no vote was cast illegitimately. The Malaysian vote did not follow the proper voting procedures. In order to vote no you had to provide technical justification for your no vote. If no justification was provided then your vote would be rejected. This is precisely what happened to Malaysia’s vote this month.

While it has not been made one-hundred percent official yet it appears that there are no further roadblocks in the path of IEC adjusting their 60335-2-89 standard. A3 refrigerants will see their charge limit increase to five-hundred grams and A2L refrigerants will see their charge limits increase to one point two kilograms. (One point one pounds on A3 refrigerants and two point four pounds on A2L refrigerants.)


While the IEC is not a governmental organization it serves as a global standard within various industries sand it is who governments look towards for guidance. The IEC ruling to increase charge limits on hydrocarbon applications will be seen as the first steps in seeing further hydrocarbon rollouts across the world.

There is a lot of debate on this decision.  Many folks have expressed concern about increasing charge limits on these highly flammable refrigerants. Obviously, the higher the charge limits the higher the chance of ignition and explosion.  But, if proper precautions are taken by both the manufacturers and the service technicians then all should be fine. All it could take though is one mistake and an incident could occur.

As we move forward from the IEC’s decision we can expect to see other countries and manufacturers beginning to adopt larger hydrocarbon applications. We may first begin to see this in Asia and then in the European Union.

The United States is quite a bit behind the times when it comes to hydrocarbons. It was just a bit ago when the Environmental Protection Agency increased the approved charge limit from fifty grams to one-hundred and fifty grams. So, we just caught up to the global standard and now it has changed again to five-hundred grams.  I predict it will be quite a while before the EPA approves five-hundred gram applications.

No matter how you feel about the IEC’s decision, this topic is another example of the safety versus climate balance. No refrigerants are perfect and while we all know the world wants to get rid of HFCs is it really worth moving away from HFCs if we are risking our own safety to do so? Personally, I think not. I believe we should hold onto HFCs until a more suitable and safer alternative is discovered.

As to what will happen only time will tell.

Thanks for reading,

Alec Johnson




Hello all, hope all is well. I wanted to do a quick post here on the status of RefrigerantHQ. Earlier this week the website was down for just over forty hours. This downtime was intentional though. You see over the past year I have had random occurrences where my website would go offline. I would have to revert to a backup and then the site would come back up without any issues. Because of this reoccurring issue I had to watch the site like a hawk to ensure that if it did go down that I would be there to catch it and correct.

Well, last week I discovered the cause of the problem. RefrigerantHQ had gotten too large for it’s current hosting and memory plan. While too much growth is always a good problem to have… it would have been nice if my provider had notified me that I was going above and beyond the memory limits. Now that I understood what the problem was I was then able to fix it. I switched hosting providers and moved up capacity substantially.

This entire process took about a week and caused the website to be down for nearly two days, but in the end I have seen a significant improvement. So far there have been no downtimes and the overall speed of the site has improved greatly. In the past it may have taken five to six seconds to load a page on RefrigerantHQ. Today, with the new hosting plan, the average load time is between two to three seconds.

While a few extra seconds may not sound like a lot, in a lot of cases those few seconds will determine if the person visiting your site loses interest and looks elsewhere in Google. On just the first day of new hosting and faster load times my traffic has gone up nearly twenty-five percent. This is great timing as we all know the busy season is just around the corner.

Diversified Growth

Having a stable site is great but that is not the only thing to mention here. As of this summer RefrigerantHQ is five years old. Over those five years I had struggled with what I wanted the site to be. I moved back and forth between different topics and ideas until I finally settled into the niche that I have today and that you all know. One hurdle that I had in the past however was that the majority of my traffic came to three or four specific articles. While the other articles received views they were nothing compared to those top tiered posts.

While it’s great to have successful articles it is also a bit nerve racking to know that most of my traffic and income comes from a select few posts. Towards the end of last year and throughout 2019 I have been working on diversifying my traffic into various articles. This is where the idea for my ‘Refrigerant Fact Sheets,’ came from. This is also why I’ve decided to expand further into other types of refrigerants. I plan to write in-depth articles on R-744, R-717, and on new and developing HFO refrigerants. These wide ranges of articles will all receive traffic and help in spreading out my views per article so that if one article starts to lose value then the others will fill in and keep the numbers up. Also, if you know of any topics of conversations that I have not featured on my site please reach out to me. I am always looking to add more content!

Another step in diversification is the growth of my mailing list. As I write this article I am just shy of two-thousand subscribers. These subscribers come from all over the world and range from HVAC technicians, contractors, refrigerant distributors/reclaimers, and refrigerant manufacturers. RefrigerantHQ is quickly becoming known throughout the industry and I have a great sense of pride that my written words have circulated across the globe.  As this mailing list continues to grow the reach of RefrigerantHQ does as well. This mailing list is also a great insurance policy in case Google decides it doesn’t like my site anymore. Having this mailing list ensures that I can still reach all of you regardless if Google decides to derank my site.


I’ve put in a lot of work on the site in 2018 and so far in 2019. I have high hopes for this summer season and hope to not only make a good profit but also to keep everyone informed within the industry. As the site continues to grow and we move into 2020 I will start seeking out advertisers within the industry. Today, I use an artificial intelligence advertiser that looks at the cookies tracked by your web browser and recommends ads to you based off of that.

While this approach is profitable it is not how I would like my site to be in the future. These ads can look spammy at times and I feel it detracts some value from the site. My goal is to sign advertisers in 2020 and slowly begin to phase out these cookie based ads. The other side of this as well is if I get enough advertisers signed on over the next few years I come closer to making RefrigerantHQ a full time reality for me and my family.

Thanks for reading and let’s all hope for a great 2019 summer season!

Alec Johnson


Today Democratic Presidential Candidate Robert O’Rourke announced his climate action plan if he was to become president after the 2020 election. Of course, all of this is very speculative as we haven’t even gone through the primaries yet. We are still a very long ways away from the election and no one knows for sure what the landscape will look by the time we get there.What is concerning though is that these announcements and policy positions made by candidates today may be carried over towards the national stage as we progress further along. Even if Mr. O’Rourke doesn’t achieve the nomination his competitors may look at some of his policies and began to adopt them for themselves.

Now, I won’t get into all of the details of O’Rourke’s plan but instead I’m going to focus on one specific excerpt that affects us the most. Here is what his campaign website states:

“Rapidly phase-out hydrofluorocarbons, the super-polluting greenhouse gas that is up to 9,000 times worse for climate change than carbon dioxide.” – Source

What concerns mere here folks is the vagueness of his comments. HFCs are mentioned almost off offhandedly in a long laundry list of other goals and desires. Reading his comments above leads me to a variety of questions:

  1. What does a rapid phase out look like? Notice also, that it is stated as a phase out and not a phase down. Will this be an immediate phase out? Or, will it be staggered?
  2. In his climate plan he states that he would enact these HFC phase outs on the very first day of his presidency via executive order. Like I mentioned above, will this be staggered or he just going to shut the hose off and leave the market scrambling?
  3. Will R-410A be included in this proposed plan? In most HFC phase downs across the United States rather it be through the EPA or individual states we have seen R-410A more or less left alone. That is because it is still fairly new as a replacement for R-22.
  4. How will R-134a be handled in this phase out? Will all new vehicles be forced over to 1234yf?
  5. Will this phase out be focused on no more new machines being produced or imported in the United States? Or, will it be focused also on manufacturing and import limits on HFC refrigerants?

Of course there are many other questions that come to mind after reading his campaign website. But, this is all speculative and at this point no one knows for sure what’s going to happen. The only thing I can hope for is that as we move closer to the election and the field begins to narrow that we get a more details and concise plan from candidates.


I try to make RefrigerantHQ political neutral. You may have seen my political leanings in differing posts, but overall I feel it’s in bad taste to advocate for one side or another on an industry specific publication. It doesn’t make sense to exclude half of your audience just because you feel a certain way.

That being said, this plan from Mr. O’Rourke does concern me for the reasons I mentioned above. It has the potential to turn the industry upside down. Imagine, if you will, that he is elected President and on his first day he bans HFCs from all new machines and puts an import/production limit on HFC refrigerants. The market would go crazy. Prices would sky rocket and shortages would occur. We would look like Europe looked like in 2017 and 2018.

O’Rourke isn’t the only Democratic candidate pushing for these types of changes though. Mr. Inslee out of Washington, whom I wrote about earlier today, is also running for President and has also voiced desire to phase out HFC refrigerants.

It’s going to be a crazy eighteen months until Election Day. Here’s hoping we get some more details on these plans and may the best candidate win!

Thanks for reading,

Alec Johnson



Another state has moved forward with phasing down HFC refrigerants such as R-404A, R-134a, and R-410A. Last week the Washington State House Bill 1112 passed the Legislature with a large majority vote. This was widely expected to pass and now all it needs is a signature from Governor Jay Inslee which is expected to happen soon.

Washington is part of what’s known as the United States Climate Alliance. This alliance is a mixture of various States that came together when the Trump Administration announced that they were pulling out of the Paris Climate Accord. These twenty-two states include New York, Washington, New Jersey, Oregon, and California. In fact, Governor Inslee of Washington was one of the co-founders of this alliance.

The Washington Bill 1112 is modeled and built off of the Environmental Protection Agency’s former SNAP Rules 20 and 21. It aims at phasing down HFCs across the state and to make certain HFCs no longer acceptable in newly built applications. I won’t report on the exact specifics on the bill until it is fully signed as there is always a chance that there will be further amendments or changes before it is fully passed.

But, from what I have read the Washington bill is very similar to the California bill that was passed last year. Let’s take a look at what California did:


The California bill adopts the rules laid out on the Environmental Protection Agency’s SNAP Rules 20 and 21. The only exception here is for automobiles. (In the SNAP Rule 20 R-134a was deemed as no longer acceptable in 2021 model years.) These prohibitions and regulations in California took effect on January 1st, of this year.

Under the new California law manufacturers can no longer produce machines that use the prohibited HFC refrigerants. Now, just like with the EPA’s SNAP, this California plan is a staggered approach. So, not all applications were phased out all at once.

California did the carrot and stick approach. Obviously, the stick is not being compliant with the new regulations and facing fines and other repercussions. The carrot though is that the government is offering incentives to businesses that begin adopting new climate friendly equipment today.

All of these changes and regulations from the Senate Bill 1013 aim at cutting California’s HFC emissions to forty percent below 2013 levels by the time we reach the year 2030. This goal is mandated by the Senate Bill 1383.

The important thing to remember here folks is that this isn’t just an on or off switch. Like I mentioned earlier, this is a staggered approach that goes by application to application. That being said, one big change that has already occurred as of January of this year is that R-404A is no longer acceptable in supermarket systems in California. Along with that 404A is no longer accepted in vending machines, cold storage facilities, and many other applications. You can read more on this by clicking here.

While R-134a and R-410A were mentioned in their table, it was only briefly and not in their primary applications. For example, automobiles were not mentioned and home/commercial air conditioners were not mentioned. So, for the foreseeable future your air conditioner for your home and car will still be using HFCs in California without issue. All of that may change though folks as you never know what new law will come down the pipeline.


California was the first but there will be many more to follow. Washington will be next. Who knows who will come after that?

One thing is for certain, the United States Climate Alliance is a large collection of states and it is only getting larger as time goes on. As the dominoes began to fall we will eventually see manufacturers be forced to move away from HFC machines if they want to continue selling in Climate Alliance states.

Thanks for reading,

Alec Johnson



A Look

I’ll be the first to admit that I know very little when it comes to a transcritical system. I have seen it mentioned numerous times and have also seen that it is starting to become a trend in certain newer environmentally friendly applications. In an effort to educate myself I’m going to take a look at transcritical systems and how they work in this article.

We are all familiar with subcritical refrigeration process. This is the same process that is used in most every air conditioner or refrigerator across the world. It consists of four specific processes known as evaporation, compression, condensation, and expansion. A subcritical system has ALL of it’s processes occur below the refrigerant’s critical temperature.

When parts of the cycle process take place at pressures above the critical point and other parts below the critical pressure the cycle process is referred to as transcritical cycle. Transcritical systems are found when using R-744 Carbon Dioxide refrigerant. This is due to R-744 having an extremely low critical temperature of thirty-one degrees Celsius. As a comparison, R-134a has a critical temperature of one-hundred and one degrees.

There are many cases where the ambient temperature could be between twenty-five to thirty degrees Celsius. If your critical point for R-744 is only at thirty degrees then how can you expect to remove the heat?

Difference of Subcritical & Transcritical

The key difference with transcritical systems is that the heat rejection process is different. There is in fact no condensation. This is due to the low critical temperature of certain refrigerants. In transcritical systems the heat rejection takes place at temperatures above the refrigerant’s critical temperature.

When a refrigerant reaches a temperature above it’s critical point it is no longer known as a gas or a liquid but instead known as a fluid. This fluid condition is also known as a gas condition or state. So, when rejecting heat with a transcritical system it is known as ‘gas cooling.’ Therefore the heat exchanger in an transcritical system is known as a ‘gas cooler.’

Besides the difference in heat rejection though the rest of the refrigerant cycle remains the same. We will go into the transcritical process in our next section:

The Process

A transcritical process begins with the compressor just like it does with a subcritical system. The difference here though is that as the compressor compresses the vapor refrigerant the temperature rises and rises until it reaches past the refrigerant’s critical temperature. This is where the state change differs. Instead of a liquid we get a state in between liquid and vapor known as fluid.

The next step in the process is the rejection of the heat gained from compressing the vapor. The heat exchanger, or gas cooler, expels the heat all the while having the temperature staying above the critical point. During this process you will also have the temperature vary between the point it left to the compressor to when it goes to the expansion valve.

Next, as you know, is the expansion process. At the time the refrigerant comes into the expansion vale it is above the critical temperature and in a fluid state. When leaving the expansion valve the refrigerant is no longer above the critical temperature and it is a mixture state of liquid and vapor.

Lastly, we are at the evaporator. In the evaporator the refrigerant comes in as a liquid at a constant pressure. Obviously, during the evaporation cycle we change states again to vapor that is slightly superheated. The vapor then makes it’s way to the compressor to start the process over again.

One thing to note that with a transcritical system superheat and subcooling temperature aren’t as important. While they can still be helpful, most folks only look at evaporating and condensing temperatures. In fact, with a transcritical system there is no condensation process and therefore no subcooling.


Are There CO2 Systems That Aren’t Transcritical?

  • Yes, most often these are found in what’s known as cascade systems. These systems contain two types of refrigerants. In these examples the CO2 refrigerant is used during the low temperature stage of the refrigerant cycle. This ensures that the refrigerant does not rise above the critical temperature.

Are there other popular transcritical refrigerants?

  • From what I have researched CO2/R-744 is the only transcritical systems used today. I also went through a list of all refrigerants and their critical temperature and only found a few that were very low. R-744 was the only common one that I found that is used today. If you know otherwise, please reach out and let me know.
    • One reader reached out to me and informed me that in some cases R-410A can be used in a transcritical system. That is because 410A’s critical temperature is only one-hundred and sixty-two degrees Fahrenheit. If you are in a warmer climate, in the summer, and the sun is beating down on a rooftop condenser then temperatures could very well come close tot hat one-hundred and sixty degrees mark.

How often do we use transcritical systems?

  • With constantly improving technology and the push to move the worlds towards greener refrigerants we are seeing a substantial rise in transcritical systems across the globe. Most of these new systems are found in Europe and other countries but the United States is making inroads as well. We’re always just a bit behind Europe though…

Are transcritical systems more expensive?

  • Yes, they are when compared to traditional HFC systems. This is especially true here in the United States as there aren’t as many technicians who are familiar with the technology and the parts aren’t as readily available. In the US these systems are nearly twice as expensive but in the EU they are only around thirty percent more.
  • The good news here is that CO2 systems are slightly more efficient then HFC systems and the cost of R-744 refrigerant is significantly cheaper then HFC refrigerants.

Why Should I Choose a Transcritical CO2 System?

  • Yes these R-744 systems are more expensive but you get peace of mind with a transcritical CO2 system. They are never going to be phased out like a R-404A application will be. CO2 has a negligible environmental impact and will be around for decades to come. It is a safe investment in the future of your business.


Well folks I learned quite a bit during writing this article. I had to dig through some articles to educate myself. All of my sources articles can be found below. If you have further interest in learning about transcritical systems then I highly recommend the first two sources from ACHRNews & Danfoss. These articles are great and go in-depth on the transcritical process as well as including diagrams and illustrations to help drive the points home.

Thanks for reading,

Alec Johnson



Well folks, as most of you know today is Earth Day. Personally, I don’t do anything to celebrate it besides walking around my property and enjoying the view. I just cleared an area by our pond this weekend and now I’ve got a nice quiet place to relax after a day’s work.

As I was reading the news today I saw a plethora of Earth Day stores. One that stuck out to me though was that the Environmental Investigation Agency (EIA) announced that they had launched a website in honor of Earth Day. This website aims at identifying retailers within the United States who have begun to use natural refrigerants instead of HFCs. The goal here is to have the companies who have started moving forward with natural refrigerants to be recognized for leading the pack.

Before we get to the website, let’s take a look at who the Environmental Investigation Agency (IEA) is. I have not heard of them before, and when I haven’t heard of something I like to research it. EIA is a non-profit organization that was founded back in 1984 out of the United Kingdom. Today they have offices in London and in Washington DC and focus on environmental crime and abuse across the globe. Their main website can be found by clicking here. They work on wide variety of things from endangered animals and poaching all the way over to climate change and refrigerants.

The new HFC website that EIA created can be found by clicking here. At first glance when looking at this website and the map that shows you where the natural refrigerant supermarkets are within the United States I couldn’t help but laugh. Nearly every location is in California or New York. This was expected as California usually leads the way in environmental progress, but still it was quite funny to see that the closest one to me is about one-thousand miles away (I’m in Kansas City).

Regardless of how far away they are progress is progress. According to IEA there are five main companies that have been pushing their locations to move away from HFCs and switch over to natural refrigerants. These companies are: Target, Aldi, Ahold Delhaize, Whole Foods Market, and Sprouts. Each of these companies has their own innovative ways of applying these alternative refrigerants. These range from:

  • Transcritical CO2 systems
  • Cascade or indirect systems using a combination of two low-GWP refrigerants
  • Micro-distributed systems using hydrocarbon condensing units on a chilled water or glycol loop
  • Stand-alone display cases using hydrocarbons

I won’t get into the details of what every company has done over the past few years to make this listing, but instead give you a quick highlight from each company. If you wish to read more on the subject feel free to visit our ‘Sources’ section at the bottom of this article to continue reading.

Aldi has been one of the leaders here in the United States. This isn’t surprising in the slightest as they are a European based company and have European ideals. (Europe is always ahead of us when it comes to environmental changes.) According to IEA Aldi has over two-hundred stores with transcritical R-744 systems with plans to add another one-hundred by the end of 2019. Along with that they have launched R-290 propane self-contained refrigerators/freezers and they have transitioned their warehouses over to R-717 ammonia based systems.

Target is another big driver of change. So far they have over one-thousand stores using self-contained hydrocarbon refrigerators/freezers (R-290 and R-600a). They have also begun experimenting with CO2 applications. They are piloting a transcritical R-744 application in two stores and they have also begun using CO2 cascade systems in their larger stores. Also, just like Aldi, they are using ammonia R-717 in their food distribution warehouses.

The other stores haven’t done as much as Aldi and Target, but they are still making strides to cleaner refrigerants. Whole Foods, now owned by Amazon, has begun distributing propane stand-alone refrigerators/freezers across their entire store network. They have also been piloting a transcritical CO2 system in their Brooklyn, New York store. The company Ahold USA was the very first store ever in the United States to begin using a transcritical CO2 system. Lastly, Sprouts was the first grocery store in the United States to use a R-744 ejection refrigeration system.


Along with these companies being environmentally friendly and being recognized by such agencies such as the IEA they also get the added benefit of increased energy efficiency. More often than not natural refrigerants are far more efficient than your standard HFC refrigerant. Ammonia, for example, is the most efficient refrigerant out there. All of this efficiency means decreased monthly energy bills for these stores and companies. So, while there may be a larger expense up front with a natural system the business owner will make it back month to month with lower operating expenses. They also get the peace of mind knowing that natural refrigerants will never be phased out by the Environmental Protection Agency as they have no, or extremely little, impact on the climate and the Ozone layer.

While looking at the map of all of stores using natural refrigerants was comical, we do all have to start somewhere. I’m willing to bet though that the map isn’t covering every store in the country. There’s a Whole Foods and an Aldi not far from me and I bet one of those stores are using a propane based refrigerator. With each year that passes the chance of running into these systems increases. If you haven’t already familiarized yourself with them I would recommend looking into it soon.

What is interesting though was after reading this I saw very little mention of HFO refrigerants from Honeywell and Chemours. Are the HFO refrigerants being eclipsed by natural refrigerants?  Will we begin to see the mass conversion away from R-404A before HFOs can be fully rolled out? Time will tell.

Thanks for reading,

Alec Johnson



Alarm Alert

Hello all, I apologize for the two e-mails in one day but I figured this one was worth it. Over the past week I have had a few notifications from my contacts within the industry about incoming price changes.

First, before we get into what these changes are I want to take a look at why they are occurring. A few years back there was a suit filed with the International Trade Commission. This suit claimed that refrigerants from China were being dumped into the United States market at unfair prices. This dumping caused the prices on the most common HFC refrigerants to sink lower and lower.

In 2016 the Trade Commission ruled in favor of tariffs on imported HFC refrigerant blends from China (Two-hundred and ten percent tariff – Source from CoolingPost.com) The problem here though was that the Trade Commission’s ruling was on on HFC blends and not their components. That meant if you imported R-410A into the United States from China you would face a two-hundred and ten percent tariff, but if you imported R-125 and R-32 from China and then blended them within the US then you could work around the tariffs.

Obviously, this was a big hole. With this ruling there was going to be very little impact on HFC blend pricing. Sure, there is the extra cost of having to blend the product, but it is minimal when compared to purchasing competing product. The low priced product from China continued to flow freely.

The New Case

Everyone knew that the anti-dumping tariff had to be put in place on the components of blended refrigerants as well. But, in order to justify a new case with the Trade Commission it had to be proven that the tariffs instigated in 2016 were not effective and that companies were navigating around them by importing component refrigerants. From what I have read there needs to be at least a couple years of data in order for a case to move forward and be legitimized.

Well folks, here we are in 2019 and years have passed since the initial anti-dumping tariffs were passed. It is now time for a new case with the International Trade Commission. Yes, on April 4th, 2019 the American HFC Coalition and it’s members filed a new anti-dumping case with the Trade Commission. An excerpt can be seen below:

Section 781(a) of the Act is designed to address circumvention of an order by imports of out-of-scope merchandise, such as HFC components, that are completed or assembled in the United States after importation. As described below, the statutory criterion for initiating an anticircumvention inquiry are satisfied in this case. Evidence establishes that iGas USA, Inc., and its affiliate BMP USA, Inc., are mixing HFC blends in the United States using HFC components imported from China.

The process of blending HFC components from China into in-scope HFC blends adds only [ ] per kilogram of the finished HFC blend. As such, the blending performed by iGas and BMP is “minor or insignificant” within the meaning of section781(a)(1)(C) and 781(a)(2) of the Act. Additionally, the imported R-32, R-125, or R-143a, as the primary inputs of HFC blends, account for a “significant portion” of the total value of the merchandise within the meaning of section 781(a)(1)(D) of the Act. For these reasons, HFC components imported from China by TTI, Lianzhou, iGas and BMP are circumventing the antidumping duty order on HFC blends. Consequently, these components should be included within the antidumping duty order on HFC Blends from China pursuant to Section 781(a) of the Act.

As you can see, they have referenced companies bringing in HFC components from China and then mixing them in house to create R-410A, R-404A, and other popular HFC blends. Here is where things get a bit different though folks. Most people within the industry knew that this was coming. They had expected it to hit this year even, but what’s different is that the expected case was to be on the component refrigerants coming in from China. This new case though aims at the actual blending process. If you import HFC components into the United States from China and you then use those components to create a refrigerant blend that has a tariff then that tariff will apply to your newly blended refrigerant. In other words, you will be charged the tariff on R-410A even though you didn’t actually import R-410A. (You imported R-125 and R-32 instead.) An excerpt from the case is below as well:


All of this is preliminary. There is nothing official yet. The Trade Commission hasn’t even decided if they are going to investigate the matter. Their decision is expected to come towards the end of May. If the Commission does decide to investigate this case then we may have to wait a year, or more, to find out what the results are and if they will be levying a tariff on the blending of HFC refrigerants. Here’s the kicker though folks, if they do accept this case and rule in favor of a tariff a year down the road they could also make the decision to retroactively enact the tariff on blending refrigerants. That means that from the moment they accept the case up until their ruling refrigerant distributors could have to pay the new tariffs on their blended refrigerants… even on product that have already been sold. This is a worst case scenario, but if it does happen a lot of companies will have to write off these tariffs on product that they sold a year ago.

Price & Availability

As a direct result of the scenario above we have begun to see chaos in the HFC pricing and availability market here in the United States. In just a few days after the announced case two major refrigerant manufacturers sent notifications that they would no longer be accepting HFC refrigerant orders. Think about that for a second, two out of the four major manufacturers are no longer accepting orders. (I won’t name names here, but I’m sure you can make a good guess.) These companies put a hold on their distributing refrigerant because everyone is buying as much refrigerants as they can as soon as they can. Everyone is trying to beat that May deadline when the Trade Commission decides rather to pick up the case or not. That date is critical because, as we discussed before, if they do decide to investigate then ANY product brought in after that date could be subject to an anti-dumping tariff.

Along with the two manufacturers who are no longer taking orders I have another mailer from a third global manufacturer. While this mailer isn’t stopping orders it is announcing a large price increase on all of their HFC refrigerants. This company announced an increase of eighty cents a pound on their various HFC refrigerants such as: R-410A, R-407A, R-407C, R-404A, and R-507. For some reason, R-134a was also mentioned as having an increase although theirs was smaller at sixty cents more per pound. Having R-134a in here is strange since it is not a blended refrigerant, but this may have been thrown in there just because.

Based off of the increases mentioned above let’s take a look at one of the most popular refrigerants and how they are impacted. Remember, that these prices are always ball park and can change at any time:

R-410A – Twenty-Five Pound Cylinder Pricing:

  • Fall 2017 – $140
  • Fall 2018 – $65
  • Jan 2019 – $68
  • Feb 2019 – $56
  • Mar 2019 – $49
  • Apr 2019 – $100

R-404A – Twenty-Four Pound Cylinder Pricing:

  • Fall 2017 – $175
  • Fall 2018 – $80
  • Jan 2019 – $70
  • Feb 2019 – $58
  • Mar 2019 – $50
  • Apr 2019 – $105


These two pricing trends above really tell the story on what has happened over the past week or so. The prices on these HFC blends have nearly doubled. ALL of this is due to speculation and rumor as to what the Trade Commission will decide. Will they take up the case? Or, will they hold off? 

Also, another point that I didn’t mention is that it’s not just the larger global manufacturers that are having a run on their HFC inventory. The Chinese are seeing huge trailerload orders placed as a last ditch effort to get as much product on hand as possible before a possible tariff begins. If this keeps up there very well may be a global shortage of R-125 again similar to what we saw in the spring of 2017. (At some points during that year we saw 410A and 404A prices upwards of four-hundred dollars.)

The only good news I can offer here is that once the May deadline approaches things began to slow down. Right now it is the uncertainty that is driving the market mad. At least once a decision is made everyone can sleep a bit easier. 

Thanks for reading,

Alec Johnson


Flammable Refrigerants

Last Friday the International Electrotechnical Commission (IEC) voted against increasing the charge limits on flammable hydrocarbon refrigerants such as propane (R-290) and isobutene (R-600a). The proposed changes aimed at increasing the global standard charge limit to five-hundred grams. Today, the International Standard known as IEC 60335-2-89 limits hydrocarbon A3 refrigerants at a charge of one-hundred and fifty. In order for it to pass the amendment needed a three quarters approval. It failed by one vote.

The International Electrotechnical Commission is an international standards organization that reviews, prepares, and publishes worldwide standards for electrical and other technologies. The group is made of nearly twenty-thousand experts from various industries. Their goal is to provide the companies, governments, and industries standards to follow when working with specific equipment. You can read more about them by clicking here.

Over the past decade or so there has been a large push to get back to the basics when it comes to refrigerants. Hydrocarbons were one of the very first refrigerants used way back in the 1800s. Back then, they were used because they were naturally found within the environment, were easily accessible, and performed efficiently. The problem with them back then, and in today’s world, is that they are highly flammable. Their flammability posed a potential risk and as soon as CFCs and HCFCs were synthesized we began to see a decline in hydrocarbon usage.

The push for hydrocarbons today comes from them being so environmentally friendly. Hydrocarbons have no Ozone Depletion Potential and they have very low, sometimes non-existent, Global Warming Potential. In order to use these climate friendly refrigerants while being conscious of their flammability many governments and organizations have imposed charge limits. By limiting the charge the risk of explosion is much lessened.

As a global standard IEC had a maximum charge of one-hundred and fifty grams as we mentioned above. Other governments have their own specific regulations, but they more or less follow the standard which is one-hundred and fifty grams. Here in the United States we were a bit behind the times. Up until a few years ago the maximum charge allowed by the EPA was fifty-seven grams. Most applications today have been approved by the EPA’s SNAP up to one-hundred and fifty grams. But, this was a recent development and you will still certain applications only allowing up to fifty-seven grams.

The hope from Friday’s decision was that the IEC would rule in favor of the five-hundred gram charge. This ruling would then inspire other governments and regulatory agencies to move forward with higher charged systems. It would be a cumulative effect across the world that would allow us to see hydrocarbons used in larger applications.

IEC’s ruling is disappointing to many. All is not lost though. The amendment will go back to a sub-committee where they will revisit the issue. They may end up making revisions so that it is not as such an aggressive change. In the meantime, we may see other countries move forward with their own increase in charge.

It is a delicate decision. Yes, there is a lot of pressure on having climate friendly refrigerants, but that doesn’t mean we should dive into flammable refrigerants. There has to be a balance between safety and climate. This balance may mean we need steer more towards less flammable refrigerants such as HFOs. Hydrocarbons will always have their place in their world but their growth into newer applications will be limited this latest ruling. This story broke from Hydrocarbons21.com.


Alec Johnson



It is human nature. If the demand is high enough then the market will provide. It doesn’t matter if the product is illegal or not. If there are people willing to pay for it than others will provide the product, even if there is great risk involved.  When most people hear the terms ‘black market’ they think of various drugs and or weapons. These items are sold under the radar of government agencies and often times at great profit.

While the above items are mostly illegal there is another kind of black market that can occur when a product is strictly regulated, refrigerant for example. By now, we all know the amount of regulations, rules, and restrictions that are in place on various refrigerants across the globe. To complicate things more these regulations can change from country to country and now state to state.  Due to these regulations the price of refrigerant has risen significantly in certain parts of the world. Eventually, there was a breaking point where the increased price meant substantial profits to those who were willing to bypass the law.


The large majority of illegal refrigerants are being found within the European Union. The CoolingPost.com has done a fantastic job about reporting every one of these instances. I’m not going to go into every documented case here but to start reading on some of these scroll to the bottom of our article under the ‘Sources’ section.

Instead, in this section we’re going to focus on why and what kind of illegal trade is occurring. The biggest violation in Europe is under the ‘F-Gas’ quota system.  Just like here in the United States, the EU has a quota on how much a specific refrigerant can be produced or imported into the EU. The difference here is that Europe has begun phasing down HFC refrigerants such as R-134a, R-404A, and R-410A. The phase down came with a very aggressive import/production quota similar to what we have on R-22. This aggressive phase down caused the prices on HFC refrigerants in Europe to go up hundreds of percent. I recall reading that at one point a cylinder of R-404A was going for over seven-hundred dollars.

That crazy price point was a prime target for illegal trade. Companies from outside of the European Union saw a window of opportunity for a hefty profit. Let’s think about it for a moment. A cylinder of R-404A from China could cost around fifty dollars. If you could smuggle multiple pallets of 404A into Europe and sell it for a hundred bucks less than the going rate then the reward would be huge. For argument’s sake let’s say five pallets at forty cylinders each. So, two –hundred cylinders selling at five-hundred dollars a cylinder equals out to one-hundred thousand dollars in sales. Take out your ten-thousand dollars of cost for the Chinese product and you’re looking at ninety-thousand profit. (Minus transport fees.)

I have read from a few reports that the amount of illegal refrigerants flowing into Europe equals nearly twenty percent of the yearly F-Gas quota. So, best case Europe is looking at one-hundred and twenty percent of their HFC quota. This number could be even higher as there is no good way to measure all illegal imports. It is easy to see why Europe is having such an illegal refrigerant problem. Something has to be done to shrink these smuggler’s profit margins. Only then will we begin to see the number of illegal shipments shrink.

Other EU Struggles

Another struggle that the EU is facing is on non-refillable disposable cylinders.  These types of refrigerant containers have been banned in the EU since 2007. They were banned due to there always being a slight remainder of refrigerant gas leftover in the disposable cylinder. In some cases this leftover refrigerant can be as high as five percent. When disposed of this cylinder can leak out which in turn can harm the environment. The smugglers however see these disposable cylinders as another cost cutting point so that they can make even more profit on their illegal sales.

The last struggle that I have seen in Europe is online refrigerant sales.  There are refrigerants being sold on sites like Amazon, Ebay, and other EU specific sites. This wouldn’t be a problem if the buyer was certified and licensed to handle refrigerant, but in many cases the sellers on these websites do not ask for any certification details. In most cases they are willing to sell to anyone who wants it. This again, bypasses EU law. There is also no way to tell if these online sales are compliant with the F-Gas quota.

United States

The United States has not seen the scale of illegal refrigerants that Europe has. This is mostly due to the US still hanging onto HFC refrigerants. As I write this article, in April of 2019, there is still not formal HFC phase down plan for the US. Heck, we still haven’t even ratified the Kigali Amendment. Because of these factors the prices on HFCs have been relatively low. In fact, this year I am seeing some of the lowest prices on HFCs that I have seen in ten years.

That doesn’t mean that everything is perfect in the United States though. We have our problems as well. The first one I mentioned already in the European section, but I’ll mention it again here. In January 1st, of 2018 there was a new regulation that added HFC refrigerants to the refrigerant sales restriction. Before this rule, you could purchase a variety of HFCs on websites like Amazon.com or Ebay.com.  Shortly after the rule went into place there were a few stragglers on Amazon.com but after some more time the refrigerant listings on Amazon began to dissipate. The same story cannot be said for Ebay. I can pull up the website today and find numerous listings for R-22, R-134a, R-410A, R-404A, and more.  Now, in Ebay’s defense most of these listings ask for an EPA certification number before purchasing… but there is no way to know if they all do. I am one-hundred percent certain that sales are done without collecting the proper information.


Another problem in the United States is non-compliant refrigerant cans. The Department of Transportation has four main groups of pressure ratings for aerosol cans. (Source from Cornell.edu) This includes your typical household products like furniture polish, hairspray, tire shine, etc.  What determines the correct rating is the pressure of the product being filled at one-hundred and thirty degrees Fahrenheit.  The required ratings are below.

  • <140 psig = 2N (Non-Spec)
  • 140-160 psig = 2P
  • 160-180 psig = 2Q
  • >180 psig = Special Permit

R-134a at one-hundred and thirty degrees Fahrenheit is rated at 199 psig. As you can see, this puts 134a well outside the range of the 2Q can type. Products like refrigerants that are routinely higher than 180 psig have to be packaged in either a cylinder or in an aerosol can with a special permit. There are companies who specialize in manufacturing and obtaining special permit cans. (One example is ITW Sexton.) As you can imagine, a specialized can costs more than a standard 2Q can.

In another example of companies cutting corners there have been R-134a cans imported into the United States in a 2Q can. This is not only against government regulation but it can also be quite dangerous. There is a reason for this regulation. If refrigerant is packaged in an improperly rated can then there is risk of explosion.

Now, I am not going to name company names here for legal reasons and also not to publically shame. It is distasteful to do so. Instead, I wanted to educate you , the reader, that if you are working with or purchasing refrigerants cans please ensure that the refrigerant is stored in the correct can type. Sure, you might save some money with a 2Q can but you’re in violation of DOT regulations and you are also risking safety of yourself and others.


In both cases, in the European Union and the United States, the majority of this illegal product is sourced from China. In the case of Europe the product is being sneaked in through Turkey or through Russia. There are many instances where trucks are stopped and searched in Belarus or Bulgaria for illegal refrigerants.

While the world knows about these illegal refrigerants the biggest struggle is enforcing the laws on the books. Many governments are failing to impose penalties on companies who are in violation. This applies both within the United States and Europe. As an example, in the US government agencies are aware of companies importing non-compliant cans, but so far, nothing has been done about it. (At least that I am aware of, if I am incorrect please let me know.)

Over in Europe, if the government does find an illegal shipment they will often charge the truck driver and fail to follow the source of the shipment and the company behind the shipment. The driver is the pawn and without tackling the source of the problems the illegal shipments will continue.  There will be a new driver right away that is willing to take the risk.

The refrigerant black market is only going to flourish unless governments decide to crack down. While it can never be truly stopped we can at least make a dent in the amount of illegal refrigerants by strictly enforcing the laws on the books and punishing those who are defying said laws.

Thanks for reading,

Alec Johnson



Top 5

Greetings ladies and gentlemen. Hope everyone is ready for the weekend. I certainty am after the week I had. I had every intention on working on another article over the course of the week but before I knew it Friday had arrived and the week was over. On top of that my Saturday and Sunday are completely booked with either yard work or family time. So, here I am on a Friday night just after ten o’clock working on an article.

Today’s post is a bit different then my others. Typically, when I do an article I like to write it myself and provide all of the details and sources myself as well. Over the course of this week I had a few contacts at Bacharach reach out to me. They had just completed a study on leak detection and they wanted to spread the word on what their study and what their findings were. If you are an avid reader of other HVAC or refrigerant news you may have already seen other websites such as CoolingPost.com do an article on this study.

A refrigerant leak is obviously never a good thing. If you’re a home owner it can mean an expensive repair bill to fix the leak and recharge your system. If you’re a business owner that expensive repair just increased ten fold. Now, imagine if you’re dealing with an industrial refrigeration system that has thousands of pounds of refrigerant in it. That bill just keeps going up and up. This is why it is so important to identify and catch refrigerant leaks before they get out of control. Typically, the quicker the problem is found the less money you will have to pay in repairs.

On top of refrigerant leaks being expensive they are also hugely detrimental to the environment. Obviously, it matters what kind of refrigerant you’re using in but more often then not the refrigerant leaking is either hurting the Ozone or is affecting Global Warming. refrigerant either. There was a story last month that involved a seafood company not correcting their leaking R-22 units. They were then fined by the Environmental Protection Agency for not following the Clean Air Act. Leaks are serious.

The problem though when dealing with refrigerant leaks is finding and identifying the leak. You need the right equipment and the right knowledge on how to find a leak but even in the best cases a leak can be difficult to find. In fact, there are instances where leaks can come and go making it that much more difficult to find. So, how can we improve this process? How can we help our customers before the leak gets out of control?


What Bacharach has done is they have recorded leak detection data from all over the world. Over three billion samples, yes three billion. That is a huge number and an amazing amount of data at their fingertips. The aim here is to aggregate all of this data and determine what exactly are the top five refrigerant leak types. I am a big fan of this type of thing as I am a data guy and love digging into the numbers and analyzing the results.

To show these results Bacharach has created a free webinar for anyone to watch. All you need to do is fill out a simple form of name, e-mail, phone and then the webinar pops right up. The video is twenty-five minutes but it contains a lot of great information. It is narrated by Jason Ayres, a veteran at the Bacharach company with over twenty years of experience.

It’s easy to see after just a few minutes of watching the video that these guys know what they’re talking about. If you’d like to watch the video then please click here to be taken to Bacharach’s website. Again, you’ll have to fill out a short form but it only took me a few seconds.


Just so you all know, I was not compensated for this post. I did enjoy a nice dinner with the Bacharach guys here in Kansas City, but that was more of a meet and greet then anything else. We enjoyed some of that famous Kansas City barbecue! I watched this leak detection video myself and thought that it was a great resources for those of you within the industry. Check it out if you’ve got some time over the weekend or if you’ve got a slow day at the office!

Thanks for reading,

Alec Johnson


To start off with a quote from one of my favorite movies, “You ain’t no kind of man unless you got land.” – Delmar, O’Brother Where Art Thou? Well, the same can be said about tools. “You ain’t no kind of man unless you’ve got tools.” A man isn’t nothing without the right tools. I don’t care what line of work you are in, having the proper tools is essential. Along with that, having tools that are a step above can not only save you time but frustration.

Just the other day I was prepping my zero turn mower for the season and noticed I had a flat front tire. Once I jacked the mower up I got my tools out to remove the tire. Now, I could have used two wrenches to get the job done. One to hold it in place and the other to loosen the bolt. While this would have worked it would have also taken longer and also cost some frustration if one of the wrenches slipped off. Instead, I held it in place with one wrench and then used my socket wrench to loosen the bolt. Bam. It was over in just a few seconds and the tire came right off. The same logic can be applied when working on an HVAC job. It can become a whole lot harder if you don’t have the right tools on hand.Tools

The aim of this article is to layout the essential tools that an HVAC service technician will need in the field and then to also make recommendations on those very tools. I’ll be forward with you up front though that the recommendations I am providing are sourced through Amazon.com and that I will receive a percentage of the sale if you decide to purchase. However, if you return that item then my commission is lost. That is why I will only recommend quality products to ensure that you have the proper tools for the job and that you’re receiving quality items. That is also why I am doing research on the recommenced products.

In order to create this listing of tools and recommendations I went through numerous other articles on the same topic. The goal was to aggregate the information into one easily readable source. The references for this article can be found at the very bottom of the post under the title, ‘Sources.’ Also note, that you may not have to purchase all of these tools, especially if you’re working for a larger contractor. A lot of the times the contractor will provide you with SOME of these tools. It is up to you to determine which tools will be provided and which ones you need to source for yourself.

When we look at these tools we are going to divide this up by category. First we’ll start with the specialized tools that an HVAC technician. Afterwards we’ll move towards the more standard tools that most every tradesmen can’t go without and then we’ll take a look at safety. Without further ado, let’s dive in and take a look:

HVAC Tech Specific:


  • This is one of your most important tools to have with you on the job. You won’t be much of a technician if you can’t measure temperature and pressure of the system you’re working on. A lot of folks end up having a few pair of gauges they take with them. If you wanted to you could even go for the more expensive route and purchase a digital gauge, or you could stick the the tried and true classic analog gauge.
  • For an analog gauge we recommend the Mastercool 59161 2-Way Manifold Gauge Set with 3-1/8 Inch Gauges, 3-60 Inch Hoses and Standard 1/4 Inch Fittings. This gauge set will allow you to check on R-22, R-410A, R-404A and many other common refrigerants used today.
  • For a digital, or micron, gauge we recommend the Fieldpiece SMAN360 3-Port Digital Manifold with Micron Gauge. This gauge works with forty-five different refrigerants and simultaneous readings of superheat and subcooling. Just be aware though folks that digital gauges can be quite expensive.


  • Thermometers will be used routinely to help determine temperature change on the system you’re working on. And, no, it is not the same type of thermometer you give to your kid during the winter season. There is a ton of variety here when it comes to choosing a product. You can get the best of the best or a decent product and save some money.
  • We recommend the Fieldpiece ST4 Dual Temperature Meter, -58 to 2000F(-50 to 1300C). This unit comes with the reputable Fieldpiece name, has the ability to check two temperatures at once, and comes with a magnetic clip. While the magnetic clip may not seem like a big deal it is definitely a great feature to have while on the job. You just clip it to the system and you now have one less tool to hold. Just don’t forget it at the job site when you’re done!


  • Having a multi-meter with you on a job site is essential. A multi-meter will stop you from being electrocuted, which is always good! It can check for electrical currents and will let you know if voltage is found. It is best to find one that can test for alternating current, direct current, amps, temperature, and microfarads. Here at RefrigerantHQ we recommend the UEi Test Instruments DL369 Digital Clamp-On Meter.

Leak Detector

  • The choice of a leak detector is an important one. If you choose a poorly designed one, or go for a cheaper model, then you could end up costing yourself a lot of time trying to identify the source of a leak. A lot of guys will use the soap and bubbles method or even ultraviolet oil to find a leak. The leak detector will be the last resort for them. Other guys go right for the sniffer on the leak detector. Either way, you will need a quality one.
  • There are quite a few options to choose from when selecting a leak detector. I’ll offer two recommendations in this article. The first is none other then Bacharach’s H-10 Pro. This detector from Bacharach is widely considered one of the best on the market. The downside is that it can get quite expensive.
  • The other model we will recommend that isn’t quite as expensive as the Bacharach is the Fieldpiece Heated Diode Refrigerant Leak Detector. It is still a high quality detector that is about half the price of the H-10.

Vacuum Pump

  • One of the worst things you can do after repairing a customer’s system is forgetting to vacuum it out before you recharge. By not removing any air, moisture, or other impurities from the system before charging you risk contaminating the oil. The contaminated oil Having a vacuum pump is a must for any technician so that you can remove those impurities.
  • Here at RefrigerantHQ we recommend  Robinair (15500) VacuMaster Economy Vacuum Pump – 2-Stage, 5 CFM. While there are larger pumps out there this is a good basic model for contract work.

Recovery Machine

  • You’re going to need a way to get that refrigerant out of your customer’s system. Recovery machines are a must for any technician. Without one you can’t even do standard diagnosis.
  • Here at RefrigerantHQ we recommend the Robinair RG3 Twin-Cylinder Portable Refrigerant Recovery Machine – 115V AC, 60 Hz. This machine will work with all of the common refrigerants of today such as R-22, R-404A, R-410A, etc.

Refrigerant Scale

Core Removal Tool

  • This tool isn’t a must for techs out there but it can certifiably make your job easier. This will allow you to remove the valve core during refrigerant recovery to make for a much faster process. A brochure about the product can be found by clicking here.
  • We recommend the product that is found in the brochure above known as the Appion MGAVCT 1/4″ MegaFlow Vacuum-Rated Valve Core Removal Tool.

Tubing Cutters

Recovery Cylinder

  • These will most likely be provided to you by your contractor. But, in the off chance that they are not you will definitely need one of these when working on a system. That extracted refrigerant needs to go somewhere, right? You sure as hell better not vent it! Our recommend recovery tank is the MASTERCOOL 62010 Gray/Yellow Recovery Tank.

General Tools:

These tools aren’t necessarily exclusive to the HVAC world but they can come quite handy when at a job site.  Let’s take a look:


  •  This is by far one of my favorite tools. Mainly… because it’s a lot of fun and also allows you to get a lot of work done quickly. For the most part, if you need something removed or cut through then your sawzall will do it. I demolished my sub basement entirely with a sawzall and a sledgehammer. Between my metal and wood blades there wasn’t anything I could saw right through. I recommend the Milwaukee 2720-20 M18 SAWZALL. I push for this one as I’ve had a Milwaukee sawzall for years and have never had a problem with it.


  • Yes, I realize this is the most basic of all tools there is but you would be surprised how many people forget the basics. You will need both flathead and phillips head screwdrivers. A lot of people aim for the insulated handles, but these aren’t necessary. We recommend the Craftsman 8 Piece Phillips and Slotted Set, 9-47136. Some folks will opt for the adjustable screw driver set instead of having multiple screw drivers to carry around. It’s up to you, but I prefer the classics.



  • I can go on and on about hammers. I honestly couldn’t tell you why, but I have a fascination with hammers. There are so many types of them out there. It doesn’t matter what trade or job you are in a hammer is always useful. I’l tell you right now though that I’m going to try and sell you on a titanium hammer. I love these damn things. The whole concept is that you get the striking power of a heavy duty framing hammer but in an fifteen ounce package. So, you get a powerful light weight hammer.
  • Our recommended titanium hammers are either the Stiletto or the Martinez. Either one are great… just be prepared to pay a heavy price. Don’t be wary though, as this is a life time hammer. You’ll never need to buy another one again.


  • The more wrenches the better, right? Well, that’s what I always say. I don’t even know how many dam sets of wrenches I’ve got lying around in my workshop. The good news though is that if I lose one I can find another one just like it in no time! For HVAC work it is recommended to have a wrench set, a crescent wrench set, a set of allen wrenches, and a pipe wrench. For more on the various types of wrenches there are you can click here to be taken to homequicks.com complete wrench guide.


  • Having a powerful flashlight will make your life easier especially in those hard to see places like attics, basements, or even crawl spaces. I’ve seen some techs use the flashlight app on their phone, but if it was me, that wouldn’t be enough. I recommend the GearLight LED Tactical Flashlight S1000. It’s powerful, gives you plenty of light, and it’s small. There is another option though that some techs like to use as it frees their hands up. It is the DanForce LED headlamp. Yes, that’s right a head lamp. You just pop it on and flip the switch and you’ve got light without having to move your flashlight all around.

Wire Strippers/Crimpers

  • This is a very commonly used tool within the trade and is used numerous times during a job. You also don’t want to go cheap on a tool like this as it is much easier to strip the wire in one clean sweep then having to go over it again and again. Having a crimping function built in as well is a must. The crimper provides you with a great cutting tool allowing you to cut through wires and sheet metal alike. We recommend the Neiko 01924A Ultimate Self-Adjusting Wire and Cable Stripper.

Snips/Sheers & Metal Cutters

  • These tools will allow you to cut through sheet metal. They come as right handed, left handed, or straight. These can be bought individually or as a set of three. Here at RefrigerantHQ we recommend the Craftsman Evolv 3 pc. Aviation Snip Set.

Tape Measure

  • This should be just a default tool on any job even if you’re not in HVAC. Tape measures can be used to measure duct placement, air conditioner placement, and furnace placement. Be sure to get a self-locking measure that can also retract at a moment’s notice. We recommend the Stanley Tools 33-725 25-Feet FatMax Tape Measure.

Cordless Drill

  • There are so many opportunities that you will need to use a drill for and you never truly know when you’ll need one. We recommend using a twenty-four volt model for the most power. What’s that Home Improvement line, MORE POWER? I did some searching on this as it was hard to find a reputable twenty-four volt drill. What I ended up settling on was the Greenworks 24V 2-Speed Cordless Compact Drill, Two 2.0 AH Batteries included 37012B.

Staple Gun

Caulk & Caulking Gun

  • Having a caulking gun handy will allow you to clean any work you’ve done on a customer’s duct work. It also allows you to fix any mistakes you’ve made along the way without any serious damage being done. You can’t really go to wrong with this tool. Here is what I found from Amazon.

Hand Seamers

  • A hand seaming tool is designed to use with your duct work. This tool will allow you to mold the duct work by bending, flattening, or shaping as you require. Here at RefrigerantHQ we recommend the ABN Metal Hand Seamer.


  • This is a great tool to have in your arsenal. It allows you to punch openings through drywall, sheet metal, or wood whenever necessary. It also allows you to scratch as well. This can be used for marking a line before cutting. The Malco A1 USA Made Regular Grip Scratch Awl is a great choice here.

Extension Cords

  • More often then not the job site that you are working at is farther away from an outlet or power source. You could be outside on the side of the homeowner’s house or you could be in an unfinished basement that isn’t wired yet. Whatever the situation you are in it would be a whole lot nicer if you had an extension cord with you so that you could actually use some of your machines during the job. We recommend the outdoor fifty foot extension cord which can be found by clicking here.

Tool Bag & Tool Belt

  • We couldn’t wrap this article up without the most important ‘tool’ you’ll need on the job. With all of the tools we recommended above you are going to need a way to carry them around. Now, you can be like my father and carry around the Milwaukee tool bag. It’s just a big open duffel bag with everything piled into it. But, hey, it works for him so who’s to judge?
    • If you find however, that you want to be a bit more organized then we recommend getting the backpack tool bag. I’m a big fan of the backpack approach as you can carry it on your shoulders instead of with one hand to the side. It’s easier on the back that way. You also get a ton of pockets and side compartments for organized storage. There are quite a few models like this but today we’re going to recommend the Veto Pro Pac TECH PAC Service Technician Bag. Yes, I understand that it is pricey but it is one of those times where you want to spend a bit more to get that quality. Otherwise, you’re going to have to keep buying a bag every few years due to tears and rips.
    • As for a tool belt there are hundreds to choose from. Just make sure that it stays on you, isn’t too burdensome, and that it can carry what you want it to carry. We recommend the NoCry Heavy Duty Canvas Tool Pouch with 7 Roomy Pockets, 10 Tool Loops, Adjustable Waist Strap, and Sturdy Velcro Belt Flap. It’s highly rated on Amazon and after reading some of the reviews I am quite confident with it.


Safety is very important as an HVAC technician. There is a tendency for the younger generations to disregard safety. They have that mentality that nothing will happen to them and that they’ll just be fine. I know this because I was like this fifteen years or so ago. Now, I wouldn’t consider myself old but I am old enough to know better now. I take precautions nowadays and you should too especially if you’re going to be doing this job day in and day out. If you rely on your body then take care of it and take the proper steps and precautions.

Our first recommendation is having a nice pair of safety glasses. I would actually buy a couple that way if you forget a pair you have a back up. These are, along with the gloves I’m going to mention next, are some of the most important when it comes to safety. If you’re using a sawzall or even just clipping through sheet metal you never know what’s going to happen. Something could come up and fly right into your eye.  We recommend the JORESTECH Eyewear Protective Safety Glasses. You get a pack of twelve for a decent price. That way when you lose a pair, which I always do, you have a back up.

Along with the safety glasses having a nice pair of work gloves will not only make your life easier but will also serve to protect your hands from cuts, abrasions, and even frostbite if you have a nasty encounter with some refrigerant. What kind of gloves you like to purchase are up to you. Personally, I like the pig skin leather with the insulated interior. Word of the wise though, keep them somewhere secure. I made the mistake of leaving my last pair of gloves in my workshop over the winter. I went out there the other day to get something and notice a mouse had chewed them all up. Here at RefrigerantHQ we recommend the G & F 2012M-3 Cold Weather Premium Genuine Grain Pig Skin Leather Gloves with Red Fleece Lining. Again, you get multiple pairs here, three to be exact, to allow you to misplace a pair or here every now and then.

These next two aren’t as important, but they are still great to have. First, I would recommend having a set of painter’s masks either in your van or in your toolbox. These will come in handy when you’re crawling around in a moldy basement, an attic covered in insulation, or worst of all… a crawl space. For those of you who haven’t experienced before, there are a lot of homeowners who like to spray their crawl space with pesticides to ensure no bugs come in through the floor. Obviously, a painter’s mask isn’t going to solve everything and you should exercise your best caution when working jobs like this. If it doesn’t look safe, don’t do it. We recommend the Universal 4528 Non-Toxic Disposable Dust & Filter Safety Masks (50 Count Box). You get a fifty pack that should last you quite a while.

The last point I’ll mention is that it is always good to have a standard first aid kit in your van. You never truly know what’s going to happen at a job site and having a kit within reach can be extremely helpful. Even the most experienced technicians make mistakes and it only takes one to get a nasty cut either from the sheet metal or one of your tools. Having some gauze and disinfectant will help you recover and get back to the job, or limp back home! We recommend the Swiss Safe 2-in-1 First Aid Kit.


Well there you have it folks. That should be absolutely everything you would ever need during an HVAC job. I tried to be as thorough as I could with this article but if you find that you’re still wanting more information please visit our sources below. These are all great articles that have their own flair on exactly what tools an HVAC technician needs for the job.

Thanks for reading,

Alec Johnson



RefrigerantHQ's Pressure Charts

The HFO R-1234yf is the refrigerant of the future. Or, at least, that is how it has been marketed. Yf was the first HFO refrigerant to see mainstream attention. A few years back there was immense pressure in the European Union to stop using the HFC R-134a for automotive air conditioning. The pressure was there due to the extremely high Global Warming Potential (GWP) that R-134a has. R-134a has a GWP of one-thousand four-hundred and thirty. It is classified as a super pollutant.

The answer to the world’s problems came with the announcement of the new HFO refrigerant known as R-1234yf. Yf refrigerant has a Global Warming Potential of only four. That is a huge difference when comparing it to other refrigerants on the market today. The only downside for yf is that it is rated as slightly flammable or 2L from ASHRAE and other air conditioning organizations.

The European Union quickly phased down and out R-134a and had their new vehicles start taking R-1234yf. While the acceptance of yf is much slower here in the United States there are numerous vehicle manufacturers who have begun using this refrigerant in their newer model vehicles. With each year that passes more and more vehicles begin taking yf.

To read more about 1234yf please click here to be taken to our official refrigerant fact sheet on yf.

1234yf Pressure Chart

One of the very first steps when it comes to diagnosing a vehicle’s air conditioner is understanding the temperature and the current pressure that your system is operating at. Having these facts along with the saturation point, the subcool, and the superheat  numbers for the refrigerant you are working on are essential when it comes to really understanding what is going wrong with your system.

The chart below details the pressures and the saturation point, or boiling point, R-1234yf:

-94 -70 -9.82 -67.7
-90.4 -68 -9.26 -63.8
-86.8 -66 -8.65 -59.6
-83.2 -64 -7.99 -55.1
-79.6 -62 -7.27 -50.1
-76 -60 -6.49 -44.7
-72.4 -58 -5.65 -39.0
-68.8 -56 -4.73 -32.6
-65.2 -54 -3.75 -25.9
-61.6 -52 -2.69 -18.5
-58 -50 -1.55 -10.7
-54.4 -48 -0.33 -2.3
-50.8 -46 0.99 6.8
-47.2 -44 2.39 16.5
-43.6 -42 3.89 26.8
-40 -40 5.49 37.9
-36.4 -38 7.19 49.6
-32.8 -36 9.01 62.1
-29.2 -34 10.94 75.4
-25.6 -32 12.99 89.6
-22 -30 15.17 104.6
-18.4 -28 17.47 120.5
-14.8 -26 19.91 137.3
-11.2 -24 22.49 155.1
-7.6 -22 25.21 173.8
-4 -20 28.08 193.6
-0.4 -18 31.11 214.5
3.2 -16 34.29 236.4
6.8 -14 37.64 259.5
10.4 -12 41.17 283.9
14 -10 44.87 309.4
17.6 -8 48.75 336.1
21.2 -6 52.82 364.2
24.8 -4 57.09 393.6
28.4 -2 61.56 424.4
32 0 66.23 456.6
35.6 2 71.11 490.3
39.2 4 76.21 525.4
42.8 6 81.54 562.2
46.4 8 87.09 600.5
50 10 92.89 640.5
53.6 12 98.92 682.0
57.2 14 105.21 725.4
60.8 16 111.75 770.5
64.4 18 118.55 817.4
68 20 125.63 866.2
71.6 22 132.98 916.9
75.2 24 140.62 969.5
78.8 26 148.54 1024.1
82.4 28 156.77 1080.9
86 30 165.3 1139.7
89.6 32 174.15 1200.7
93.2 34 183.32 1263.9
96.8 36 192.82 1329.4
100.4 38 202.65 1397.2
104 40 212.85 1467.5
107.6 42 223.39 1540.2
111.2 44 234.29 1615.4
114.8 46 245.57 1693.1
118.4 48 257.24 1773.6
122 50 269.31 1856.8
125.6 52 281.76 1942.7
129.2 54 94.75 653.3
132.8 56 100.09 690.1
136.4 58 105.62 728.2
140 60 111.34 767.7
143.6 62 117.26 808.5
147.2 64 123.38 850.7
150.8 66 129.71 894.3
154.4 68 136.26 939.5
158 70 143 986.0



There you have it folks. I hope this article was helpful and if you find that something is inaccurate here in my chart please do not hesitate to reach out to me. I have sourced this the best I could but there is always going to be conflicting data.  I’ve seen it multiple times on various refrigerants. I’ll search for a refrigerant’s pressure chart and get various results all showing different pounds per square inch temperatures.

The aim with this article is to give you accurate information so again, if you see anything incorrect please let me know by contacting me here. On top of this post we are also working on a comprehensive refrigerant pressure/temperature listing. The goal is to have every refrigerant out there listed with a pressure/temperature chart that is easily available. 

Thanks for reading,

Alec Johnson



RefrigerantHQ's Pressure Charts

One of the very first steps when it comes to diagnosing your home air conditioner, refrigerator, or even your vehicle’s air conditioner is understanding the temperature and the current pressure that your system is operating at. Having these facts along with the saturation point, the subcool, and the superheat  numbers for the refrigerant you are working on are essential when it comes to really understanding what is going wrong with your system.

After a visual inspection the very next step for the most seasoned technicians is pulling out their gauges and checking the pressure and temperature. It just becomes second nature after enough calls. I have heard stories of rookie techs calling some of the pros on their team for help on a system that they’re stuck on. It doesn’t matter what the situation is. It doesn’t matter if you’re in Miami or in Fargo. It will never fail that one of the first questions the pros ask the rookie is what is your subcool and what is your superheat? Having  and understanding these numbers is key to figuring out what to do next.

But, these numbers won’t do you any good if you don’t know what refrigerant you are dealing with and what the refrigerant’s boiling point is at each pressure level. This article aims at providing you with just that information.

R-32 Pressure Chart

The HFC R-32 refrigerant is quickly becoming popular, more so then it already was. Most of you know R-32 as a necessary component in the widely popular HFC blend known as R-410A Puron. R-32 along with R-125 gets you that R-410A that is found in nearly every air conditioner today.

However, in recent years there has been a push to slowly phase down R-410A. That is because of 410A’s very high Global Warming Potential, or GWP. The higher the GWP the more harm the refrigerant does to the climate. R-410A has a GWP of over two-thousand whereas R-32 has a GWP of only six-hundred and seventy-five.

While R-32 isn’t perfect it is a lot better then R-410A. That is why we are beginning to see a rise of usage of R-32 in the European Union and here in the United States as well. I do not foresee this becoming a long term trend but only as a temporary place holder until the world finds a more suitable R-410A replacement.

If you would like to read more about R-32 refrigerant please click here to be taken to our refrigerant fact sheet.

Let’s take a look at our pressure chart:

-94 -70 -9.46 -65.2
-90.4 -68 -8.77 -60.5
-86.8 -66 -8.02 -55.3
-83.2 -64 -7.19 -49.6
-79.6 -62 -6.27 -43.2
-76 -60 -5.27 -36.3
-72.4 -58 -4.17 -28.8
-68.8 -56 -2.98 -20.5
-65.2 -54 -1.67 -11.5
-61.6 -52 -0.26 -1.8
-58 -50 1.28 8.8
-54.4 -48 2.95 20.3
-50.8 -46 4.75 32.8
-47.2 -44 6.69 46.1
-43.6 -42 8.78 60.5
-40 -40 11.04 76.1
-36.4 -38 13.45 92.7
-32.8 -36 16.05 110.7
-29.2 -34 18.82 129.8
-25.6 -32 21.79 150.2
-22 -30 24.96 172.1
-18.4 -28 28.34 195.4
-14.8 -26 31.94 220.2
-11.2 -24 35.77 246.6
-7.6 -22 39.83 274.6
-4 -20 44.15 304.4
-0.4 -18 48.72 335.9
3.2 -16 53.56 369.3
6.8 -14 58.68 404.6
10.4 -12 64.09 441.9
14 -10 69.79 481.2
17.6 -8 75.81 522.7
21.2 -6 82.15 566.4
24.8 -4 88.82 612.4
28.4 -2 95.84 660.8
32 0 103.21 711.6
35.6 2 110.95 765.0
39.2 4 119.07 821.0
42.8 6 127.58 879.6
46.4 8 136.49 941.1
50 10 145.81 1005.3
53.6 12 155.57 1072.6
57.2 14 165.76 1142.9
60.8 16 176.41 1216.3
64.4 18 187.53 1293.0
68 20 199.13 1373.0
71.6 22 211.21 1456.2
75.2 24 223.81 1543.1
78.8 26 236.93 1633.6
82.4 28 250.59 1727.8
86 30 264.8 1825.7
89.6 32 279.57 1927.6
93.2 34 294.93 2033.5
96.8 36 310.89 2143.5
100.4 38 327.47 2257.8
104 40 344.67 2376.4
107.6 42 362.51 2499.4
111.2 44 381.05 2627.2
114.8 46 400.24 2759.6
118.4 48 420.15 2896.8
122 50 440.79 3039.1
125.6 52 462.17 3186.6
129.2 54 484.33 3339.3
132.8 56 507.27 3497.5
136.4 58 531.02 3661.3
140 60 555.63 3830.9
143.6 62 581.1 4006.5
147.2 64 607.49 4188.5
150.8 66 634.81 4376.9
154.4 68 663.11 4572.0
158 70 692.45 4774.3


There you have it folks. I hope this article was helpful and if you find that something is inaccurate here in my chart please do not hesitate to reach out to me. I have sourced this the best I could but there is always going to be conflicting data.  I’ve seen it multiple times on various refrigerants. I’ll search for a refrigerant’s pressure chart and get various results all showing different pounds per square inch temperatures.

The aim with this article is to give you accurate information so again, if you see anything incorrect please let me know by contacting me here. On top of this post we are also working on a comprehensive refrigerant pressure/temperature listing. The goal is to have every refrigerant out there listed with a pressure/temperature chart that is easily available. 

Thanks for reading,

Alec Johnson



RefrigerantHQ's Pressure Charts

One of the very first steps when it comes to diagnosing your home air conditioner, refrigerator, or even your vehicle’s air conditioner is understanding the temperature and the current pressure that your system is operating at. Having these facts along with the saturation point, the subcool, and the superheat  numbers for the refrigerant you are working on are essential when it comes to really understanding what is going wrong with your system.

After a visual inspection the very next step for the most seasoned technicians is pulling out their gauges and checking the pressure and temperature. It just becomes second nature after enough calls. I have heard stories of rookie techs calling some of the pros on their team for help on a system that they’re stuck on. It doesn’t matter what the situation is. It doesn’t matter if you’re in Miami or in Fargo. It will never fail that one of the first questions the pros ask the rookie is what is your subcool and what is your superheat? Having  and understanding these numbers is key to figuring out what to do next.

But, these numbers won’t do you any good if you don’t know what refrigerant you are dealing with and what the refrigerant’s boiling point is at each pressure level. This article aims at providing you with just that information.

R-22 Pressure Chart

R-22 refrigerant is the major refrigerant, or… it was. R-22 was invented by a partnership with General Motors and DuPont back in the 1930’s. In the 1950’s the use of R-22 exploded and for nearly sixty years it was THE refrigerant to be used in home, office, and commercial air conditioning. Along with air conditioning it was also used in chillers, ice rinks, and many other applications.

It was in the 1980’s that it was discovered that R-22 was damaging the Ozone layer with the chlorine that it contained. In order to correct this R-22 was phased out across the world. Here in America our phase out began in 2010 and the refrigerant will be completely phased out in 2020. Taking R-22’s place is the HFC refrigerant blend known as R-410A, our Puron.

As I write this article, in 2019, there are still thousands of R-22 machines out there, but they are a dying breed and within the next ten to twenty years R-22 will be as rare to find as R-12 is today.

If you would like to read more about R-22 Freon  refrigerant please click here to be taken to our refrigerant fact sheet.

Let’s take a look at our pressure chart:

-40 -40.0 0.5 3.4
-35 -37.2 2.6 17.9
-30 -34.4 4.9 33.8
-25 -31.7 7.4 51.0
-20 -28.9 10.1 69.6
-15 -26.1 13.2 91.0
-10 -23.3 16.5 113.8
-5 -20.6 20.1 138.6
0 -17.8 24 165.5
5 -15.0 28.2 194.4
10 -12.2 32.8 226.1
15 -9.4 37.7 259.9
20 -6.7 43 296.5
25 -3.9 48.8 336.5
30 -1.1 54.9 378.5
35 1.7 61.5 424.0
40 4.4 68.5 472.3
45 7.2 76 524.0
50 10.0 84 579.2
55 12.8 92.6 638.5
60 15.6 102 703.3
65 18.3 111 765.3
70 21.1 121 834.3
75 23.9 132 910.1
80 26.7 144 992.8
85 29.4 156 1075.6
90 32.2 168 1158.3
95 35.0 182 1254.8
100 37.8 196 1351.4
105 40.6 211 1454.8
110 43.3 226 1558.2
115 46.1 243 1675.4
120 48.9 260 1792.6
125 51.7 278 1916.7
130 54.4 297 2047.7
135 57.2 317 2185.6
140 60.0 337 2323.5
145 62.8 359 2475.2
150 65.6 382 2633.8


There you have it folks. I hope this article was helpful and if you find that something is inaccurate here in my chart please do not hesitate to reach out to me. I have sourced this the best I could but there is always going to be conflicting data.  I’ve seen it multiple times on various refrigerants. I’ll search for a refrigerant’s pressure chart and get various results all showing different pounds per square inch temperatures.

The aim with this article is to give you accurate information so again, if you see anything incorrect please let me know by contacting me here. On top of this post we are also working on a comprehensive refrigerant pressure/temperature listing. The goal is to have every refrigerant out there listed with a pressure/temperature chart that is easily available. 

Thanks for reading,

Alec Johnson



RefrigerantHQ's Pressure Charts

One of the very first steps when it comes to diagnosing your home air conditioner, refrigerator, or even your vehicle’s air conditioner is understanding the temperature and the current pressure that your system is operating at. Having these facts along with the saturation point, the subcool, and the superheat  numbers for the refrigerant you are working on are essential when it comes to really understanding what is going wrong with your system.

After a visual inspection the very next step for the most seasoned technicians is pulling out their gauges and checking the pressure and temperature. It just becomes second nature after enough calls. I have heard stories of rookie techs calling some of the pros on their team for help on a system that they’re stuck on. It doesn’t matter what the situation is. It doesn’t matter if you’re in Miami or in Fargo. It will never fail that one of the first questions the pros ask the rookie is what is your subcool and what is your superheat? Having  and understanding these numbers is key to figuring out what to do next.

But, these numbers won’t do you any good if you don’t know what refrigerant you are dealing with and what the refrigerant’s boiling point is at each pressure level. This article aims at providing you with just that information.

R-404A Pressure Chart

R-404A rose to prominence in the late 1990’s with the phasing out of CFC and HCFC refrigerants like R-12 and R-502. There had to be a replacement for the Ozone damaging refrigerants of the past and the successor was the HFC R-404A that we all know of today.

404A’s reign however was short lived. R-404A has one of the highest Global Warming Potential numbers of any modern day refrigerant and is known as a super pollutant. Because of this we are seeing various countries and manufacturers no longer using R-404A in new machinery. Instead, companies and countries are opting for more climate friendly refrigerants such as natural refrigerants, hydrocarbons, and newer less GWP heavy HFO refrigerants

If you would like to read more about R-404A  refrigerant please click here to be taken to our refrigerant fact sheet.

Let’s take a look at our pressure chart:

-40 -40.0 4.3 29.6
-35 -37.2 6.8 46.9
-30 -34.4 9.5 65.5
-25 -31.7 12.5 86.2
-20 -28.9 15.7 108.2
-15 -26.1 19.3 133.1
-10 -23.3 23.2 160.0
-5 -20.6 27.5 189.6
0 -17.8 32.1 221.3
5 -15.0 37 255.1
10 -12.2 42.4 292.3
15 -9.4 48.2 332.3
20 -6.7 54.5 375.8
25 -3.9 61.2 422.0
30 -1.1 68.4 471.6
35 1.7 76.1 524.7
40 4.4 84.4 581.9
45 7.2 93.2 642.6
50 10.0 103 710.2
55 12.8 113 779.1
60 15.6 123 848.1
65 18.3 135 930.8
70 21.1 147 1013.5
75 23.9 159 1096.3
80 26.7 173 1192.8
85 29.4 187 1289.3
90 32.2 202 1392.7
95 35.0 218 1503.1
100 37.8 234 1613.4
105 40.6 252 1737.5
110 43.3 270 1861.6
115 46.1 289 1992.6
120 48.9 310 2137.4
125 51.7 331 2282.2
130 54.4 353 2433.9
135 57.2 377 2599.3
140 60.0 401 2764.8



There you have it folks. I hope this article was helpful and if you find that something is inaccurate here in my chart please do not hesitate to reach out to me. I have sourced this the best I could but there is always going to be conflicting data.  I’ve seen it multiple times on various refrigerants. I’ll search for a refrigerant’s pressure chart and get various results all showing different pounds per square inch temperatures.

The aim with this article is to give you accurate information so again, if you see anything incorrect please let me know by contacting me here. On top of this post we are also working on a comprehensive refrigerant pressure/temperature listing. The goal is to have every refrigerant out there listed with a pressure/temperature chart that is easily available. 

Thanks for reading,

Alec Johnson



RefrigerantHQ's Pressure Charts

One of the very first steps when it comes to diagnosing your home air conditioner, refrigerator, or even your vehicle’s air conditioner is understanding the temperature and the current pressure that your system is operating at. Having these facts along with the saturation point, the subcool, and the superheat  numbers for the refrigerant you are working on are essential when it comes to really understanding what is going wrong with your system.

After a visual inspection the very next step for the most seasoned technicians is pulling out their gauges and checking the pressure and temperature. It just becomes second nature after enough calls. I have heard stories of rookie techs calling some of the pros on their team for help on a system that they’re stuck on. It doesn’t matter what the situation is. It doesn’t matter if you’re in Miami or in Fargo. It will never fail that one of the first questions the pros ask the rookie is what is your subcool and what is your superheat? Having  and understanding these numbers is key to figuring out what to do next.

But, these numbers won’t do you any good if you don’t know what refrigerant you are dealing with and what the refrigerant’s boiling point is at each pressure level. This article aims at providing you with just that information.

R-410A Pressure Chart

R-410A, or Puron, is one of the most popular refrigerants in today’s modern world. However, if you rewind just fifteen or twenty years you would find that very little people even knew about it. Most contractors and technicians worked with R-22 systems for home and commercial air conditioning. R-22 had been the standard bearer refrigerant for nearly fifty years. However, R-22 harmed the Ozone Layer and a replacement refrigerant needed to be found. This is where our friend R-410A came into play. New machines from 2010 and onwards were banned from using R-22. Instead, they were outfitted with R-410A. 

If you would like to read more about R-410A  refrigerant please click here to be taken to our refrigerant fact sheet.

Let’s take a look at our pressure chart:

–37.7 -38.7 12 82.7
–34.7 -37.0 14 96.5
–32.0 -35.6 16 110.3
–29.4 -34.1 18 124.1
–36.9 -38.3 20 137.9
–24.5 -31.4 22 151.7
–22.2 -30.1 24 165.5
–20.0 -29.0 26 179.3
–17.9 -27.7 28 193.1
–15.8 -26.6 30 206.8
–13.8 -25.4 32 220.6
–11.9 -24.4 34 234.4
–10.1 -23.4 36 248.2
–8.3 -22.4 38 262.0
–6.5 -21.4 40 275.8
–4.5 -20.3 42 289.6
–3.2 -19.6 44 303.4
–1.6 -18.7 46 317.2
0 -17.8 48 330.9
1.5 -16.9 50 344.7
3 -16.1 52 358.5
4.5 -15.3 54 372.3
5.9 -14.5 56 386.1
7.3 -13.7 58 399.9
8.6 -13.0 60 413.7
10 -12.2 62 427.5
11.3 -11.5 64 441.3
12.6 -10.8 66 455.1
13.8 -10.1 68 468.8
15.1 -9.4 70 482.6
16.3 -8.7 72 496.4
17.5 -8.1 74 510.2
18.7 -7.4 76 524.0
19.8 -6.8 78 537.8
21 -6.1 80 551.6
22.1 -5.5 82 565.4
23.2 -4.9 84 579.2
24.3 -4.3 86 592.9
25.4 -3.7 88 606.7
26.4 -3.1 90 620.5
27.4 -2.6 92 634.3
28.5 -1.9 94 648.1
29.5 -1.4 96 661.9
30.5 -0.8 98 675.7
31.2 -0.4 100 689.5
32.2 0.1 102 703.3
33.2 0.7 104 717.1
34.1 1.2 106 730.8
35.1 1.7 108 744.6
35.5 1.9 110 758.4
36.9 2.7 112 772.2
37.8 3.2 114 786.0
38.7 3.7 116 799.8
39.5 4.2 118 813.6
40.5 4.7 120 827.4
41.3 5.2 122 841.2
42.2 5.7 124 855.0
43 6.1 126 868.7
43.8 6.6 128 882.5
44.7 7.1 130 896.3
45.5 7.5 132 910.1
46.3 7.9 134 923.9
47.1 8.4 136 937.7
47.9 8.8 138 951.5
48.7 9.3 140 965.3
49.5 9.7 142 979.1
50.3 10.2 144 992.8
51.1 10.6 146 1006.6
51.8 11.0 148 1020.4
52.5 11.4 150 1034.2
53.3 11.8 152 1048.0
54 12.2 154 1061.8
54.8 12.7 156 1075.6
55.5 13.1 158 1089.4
56.2 13.4 160 1103.2
57 13.9 162 1117.0
57.7 14.3 164 1130.7
58.4 14.7 166 1144.5
59 15.0 168 1158.3
59.8 15.4 170 1172.1
60.5 15.8 172 1185.9
61.1 16.2 174 1199.7
61.8 16.6 176 1213.5
62.5 16.9 178 1227.3
63.1 17.3 180 1241.1
63.8 17.7 182 1254.8
64.5 18.1 184 1268.6
65.1 18.4 186 1282.4
65.8 18.8 188 1296.2
66.4 19.1 190 1310.0
67 19.4 192 1323.8
67.7 19.8 194 1337.6
68.3 20.2 196 1351.4
68.9 20.5 198 1365.2
69.5 20.8 200 1379.0
70.1 21.2 202 1392.7
70.7 21.5 204 1406.5
71.4 21.9 206 1420.3
72 22.2 208 1434.1
72.6 22.6 210 1447.9
73.2 22.9 212 1461.7
73.8 23.2 214 1475.5
74.3 23.5 216 1489.3
74.9 23.8 218 1503.1
75.5 24.2 220 1516.8
76.1 24.5 222 1530.6
76.7 24.8 224 1544.4
77.2 25.1 226 1558.2
77.8 25.4 228 1572.0
78.4 25.8 230 1585.8
78.9 26.1 232 1599.6
79.5 26.4 234 1613.4
80 26.7 236 1627.2
80.6 27.0 238 1641.0
81.1 27.3 240 1654.7
81.6 27.6 242 1668.5
82.2 27.9 244 1682.3
82.7 28.2 246 1696.1
83.3 28.5 248 1709.9
83.8 28.8 250 1723.7
84.3 29.1 252 1737.5
84.8 29.3 254 1751.3
85.4 29.7 256 1765.1
85.9 29.9 258 1778.8
86.4 30.2 260 1792.6
86.9 30.5 262 1806.4
87.4 30.8 264 1820.2
87.9 31.1 266 1834.0
88.4 31.3 268 1847.8
88.9 31.6 270 1861.6
89.4 31.9 272 1875.4
89.9 32.2 274 1889.2
90.4 32.4 276 1903.0
90.9 32.7 278 1916.7
91.4 33.0 280 1930.5
91.9 33.3 282 1944.3
92.4 33.6 284 1958.1
92.8 33.8 286 1971.9
93.3 34.1 288 1985.7
93.8 34.3 290 1999.5
94.3 34.6 292 2013.3
94.8 34.9 294 2027.1
95.2 35.1 296 2040.8
95.7 35.4 298 2054.6
96.2 35.7 300 2068.4
96.6 35.9 302 2082.2
97.1 36.2 304 2096.0
97.5 36.4 306 2109.8
98 36.7 308 2123.6
98.4 36.9 310 2137.4
98.9 37.2 312 2151.2
99.3 37.4 314 2165.0
99.7 37.6 316 2178.7
100.2 37.9 318 2192.5
100.7 38.2 320 2206.3
101.1 38.4 322 2220.1
101.6 38.7 324 2233.9
102 38.9 326 2247.7
102.4 39.1 328 2261.5
102.9 39.4 330 2275.3
103.3 39.6 332 2289.1
103.7 39.8 334 2302.8
104.2 40.1 336 2316.6
104.6 40.3 338 2330.4
105.1 40.6 340 2344.2
105.4 40.8 342 2358.0
105.8 41.0 344 2371.8
106.3 41.3 346 2385.6
106.6 41.4 348 2399.4
107.1 41.7 350 2413.2
107.5 41.9 352 2427.0
107.9 42.2 354 2440.7
108.3 42.4 356 2454.5
108.8 42.7 358 2468.3
109.2 42.9 360 2482.1
109.6 43.1 362 2495.9
110 43.3 364 2509.7
110.4 43.6 366 2523.5
110.8 43.8 368 2537.3
111.2 44.0 370 2551.1
111.6 44.2 372 2564.9
112 44.4 374 2578.6
112.4 44.7 376 2592.4
112.6 44.8 378 2606.2
113.1 45.1 380 2620.0
113.5 45.3 382 2633.8
113.9 45.5 384 2647.6
114.3 45.7 386 2661.4
114.7 45.9 388 2675.2
115 46.1 390 2689.0
115.5 46.4 392 2702.7
115.8 46.6 394 2716.5
116.2 46.8 396 2730.3
116.6 47.0 398 2744.1
117 47.2 400 2757.9
117.3 47.4 402 2771.7
117.7 47.6 404 2785.5
118.1 47.8 406 2799.3
118.5 48.1 408 2813.1
118.8 48.2 410 2826.9
119.2 48.4 412 2840.6
119.6 48.7 414 2854.4
119.9 48.8 416 2868.2
120.3 49.1 418 2882.0
120.7 49.3 420 2895.8
121 49.4 422 2909.6
121.4 49.7 424 2923.4
121.7 49.8 426 2937.2
122.1 50.1 428 2951.0
122.5 50.3 430 2964.7
122.8 50.4 432 2978.5
123.2 50.7 434 2992.3
123.5 50.8 436 3006.1
123.9 51.1 438 3019.9
124.2 51.2 440 3033.7
124.6 51.4 442 3047.5
124.9 51.6 444 3061.3
125.3 51.8 446 3075.1
125.6 52.0 448 3088.9
126 52.2 450 3102.6
126.3 52.4 452 3116.4
126.6 52.6 454 3130.2
127 52.8 456 3144.0
127.3 52.9 458 3157.8
127.7 53.2 460 3171.6
128 53.3 462 3185.4
128.3 53.5 464 3199.2
128.7 53.7 466 3213.0
129 53.9 468 3226.7
129.3 54.1 470 3240.5
129.7 54.3 472 3254.3
130 54.4 474 3268.1
130.3 54.6 476 3281.9
130.7 54.8 478 3295.7
131 55.0 480 3309.5
131.3 55.2 482 3323.3
131.6 55.3 484 3337.1
132 55.6 486 3350.9
132.3 55.7 488 3364.6
132.6 55.9 490 3378.4
132.9 56.1 492 3392.2
133.3 56.3 494 3406.0
133.6 56.4 496 3419.8
133.9 56.6 498 3433.6
134 56.7 500 3447.4
134.5 56.9 502 3461.2
134.8 57.1 504 3475.0
135.2 57.3 506 3488.7
135.5 57.5 508 3502.5
135.8 57.7 510 3516.3
136.1 57.8 512 3530.1
136.4 58.0 514 3543.9
136.7 58.2 516 3557.7
137 58.3 518 3571.5
137.3 58.5 520 3585.3
137.6 58.7 522 3599.1
137.9 58.8 524 3612.9
138.3 59.1 526 3626.6
138.6 59.2 528 3640.4
138.9 59.4 530 3654.2
139.2 59.6 532 3668.0
139.5 59.7 534 3681.8
139.8 59.9 536 3695.6
140.1 60.1 538 3709.4
140.4 60.2 540 3723.2
141 60.6 544 3750.7
141.6 60.9 548 3778.3
142.1 61.2 552 3805.9
142.7 61.5 556 3833.5
143.3 61.8 560 3861.1
143.9 62.2 564 3888.6
144.5 62.5 568 3916.2
145 62.8 572 3943.8
145.6 63.1 576 3971.4
146.2 63.4 580 3999.0
146.7 63.7 584 4026.5
147.3 64.1 588 4054.1
147.9 64.4 592 4081.7
148.4 64.7 596 4109.3
149 65.0 600 4136.9
149.5 65.3 604 4164.4
150.1 65.6 608 4192.0
150.6 65.9 612 4219.6
151.2 66.2 616 4247.2
151.7 66.5 620 4274.8
152.3 66.8 624 4302.3
152.8 67.1 628 4329.9
153.4 67.4 632 4357.5
153.9 67.7 636 4385.1
154.5 68.1 640 4412.6
155 68.3 644 4440.2
155.5 68.6 648 4467.8
156.1 68.9 652 4495.4
156.6 69.2 656 4523.0
157.1 69.5 660 4550.5
157.7 69.8 664 4578.1
158.2 70.1 668 4605.7
158.7 70.4 672 4633.3
159.2 70.7 676 4660.9
159.8 71.0 680 4688.4
160.3 71.3 684 4716.0
160.8 71.6 688 4743.6
161.3 71.8 692 4771.2
161.8 72.1 696 4798.8


There you have it folks. I hope this article was helpful and if you find that something is inaccurate here in my chart please do not hesitate to reach out to me. I have sourced this the best I could but there is always going to be conflicting data.  I’ve seen it multiple times on various refrigerants. I’ll search for a refrigerant’s pressure chart and get various results all showing different pounds per square inch temperatures.

The aim with this article is to give you accurate information so again, if you see anything incorrect please let me know by contacting me here. On top of this post we are also working on a comprehensive refrigerant pressure/temperature listing. The goal is to have every refrigerant out there listed with a pressure/temperature chart that is easily available. 

Thanks for reading,

Alec Johnson