One of the very first steps when it comes to diagnosing a home air conditioner, refrigerator, a vehicle’s air conditioner, or a commercial cooler is understanding the temperature and the current pressure that the 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 are 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-455A Solstice L40X Basic Info & PT Chart
R-455A is another newer refrigerant from the Honeywell Corporation under their Solstice brand. The actual brand name of this refrigerant is Solstice L40X. Like a lot of the other newer refrigerants this is classified as an Hydrofluoroolefins refrigerant (HFO). It is a zeotropic blend of R-1234yf (75.50%), R-32 (21.50%), and R-744 (3.00%). This refrigerant was designed as an alternative for low, medium, and high temperature applications. In most cases it was meant to be used in newer systems but there are cases where it can be used to retrofit older systems. Just note that you will have to take all of the proper steps for a full retrofit and you will most likely need to change the oil as well (R-455A uses POE oil).
L40X aims to replace some of the more popular refrigerants such as R-404A, R-22, and R-407C. It has a very close capacity level to that of R-404A and nearly matches the efficiency of 404A as well. R-455A can be used to replace R-290 Propane systems, but I’m not really sure why you would want to replace these applications. Just like the refrigerants I mentioned, R-455A works well in plug-in cabinet applications, cold/freezer rooms, chillers, heat pumps, and other types of commercial and industrial refrigeration.
The great selling point with this newer refrigerant is the GWP number. To understand the difference let’s first look at R-404A’s GWP number of nearly four-thousand. Now, we can really understand why R-455A’s GWP number of one-hundred and forty-six is so significant. That is an amazing difference between the two refrigerants. Since this refrigerant is under the one-hundred and fifty GWP number it also makes 455A F-Gas compliant with the European Union. That means that this refrigerant can be used through the EU without the risk of possible phase down. In fact Emerson Technologies, out of Missouri, has already announced that they will be using R-455A in some of their newer compressor builds.
There is a downside to this refrigerant though folks. Like most HFO refrigerants this one is rated as an A2L from ASHRAE. The A stands for non-toxic but the ‘2L’ stands for mildly flammable. All of the other refrigerants that this Solstice brand aims to replace are NOT flammable. They are all rated as an A1 from ASHRAE. What this means is that if you use this refrigerant then you are moving to increased risk. Your previous system had no flammability risk and this newest one with R-455A does. As the rating states, the risk is ‘mild.’
Something else to note is that the ‘2L’ rating from ASHRAE is newer. If you rewind about ten years ago there was no ‘2L’ rating. Refrigerants were either flammable, or they weren’t. Since the introduction of the HFO refrigerant line from Chemours and Honeywell we began to see the introduction of the ‘2L’ or mildly flammable refrigerant rating. This new rating is meant to distinguish itself from the other flammability ratings of 1, 2, and 3.
If you can get over the medium flammability risk that comes with this refrigerant then R-455A L40X is a great long term refrigerant. So many of these newer HFO refrigerants still have a higher Global Warming Potential number which will ultimately result in them being phased out in five or ten years. But, since R-455A’s GWP is under that one-hundred and fifty mark I can see it lasting for a long time. There shouldn’t be any pressure to phase this refrigerant out in the near future. If I was purchasing a new system I would either consider this Solstice refrigerant, a hydrocarbon, or a natural refrigerant. Each one has its downsides/upsides, so the decision ultimately lies on you.
Alright folks, I’ve written enough though on this refrigerant. I know the reason you came here was for the pressure table and you can view it below. As you are viewing this table please let me know if you see anything that is incorrect or if I have missed anything. I aim to have this website as accurate as possible.
|PSIG||kPA||Liquid Temp (F)||Liquid Temp (C)||Vapor Temp (F)||Vapor Temp (C)|
Thanks for reading,