by Alec Johnson
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, thesubcool, and thesuperheat 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 eachpressurelevel. This article aims at providing you with just that information.
R-452A XP44 Basic Info
R-452A is a newer refrigerant that falls into the Hydrofluoroolefins classification family (HFOs). It can also be found under the Opteon XP44 brand name from Chemours. It is a zeotropic blend of R-1234yf (30%), R-32 (11%), and R-125 (59%). This refrigerant was designed to be an alternative to the extremely high Global Warming Potential refrigerants R-404A and R-507. R-452A closely matches the performance and energy efficiency of R-404A. You’ll also find that the compressor discharge temperature nearly matches when compared to R-404A/R-507 systems in both low and medium temperature applications.
While this newer refrigerant can be used in various commercial/industrial refrigeration, condensing units, and stand alone plug-ins you are most likely to find this refrigerant being used in transport refrigeration. These are your refrigerated trucks, vans, or reefer containers. This niche application is forgotten by a lot of folks but the sheer amount of refrigerated trucks that are out there is staggering. Think about it for a moment. All of the meat, dairy, and any other cold groceries are delivered by these refrigerated trucks. All of the meat being transported from processing plant to distributor use a refrigerated truck. Heck, even the ice cream truck that rolls down your neighborhood falls under this application.
452A XP44 is ideal for newer applications but can also be used for retrofits of existing systems. It uses POE oil so in most cases you’ll find that you do not even need to swap the oil as R-404A uses POE as well. The refrigerant is also rated with an A1 safety rating from ASHRAE. What that means is that it is non-flammable and non-toxic just like R-404A is rated.
I had mentioned earlier that the idea behind this refrigerant was to provide an alternative to the extremely high GWP that is R-404A. You see R-404A has a GWP number of nearly four-thousand! That is a huge number. The good news here is that with R-452A it reduces the GWP by forty-five percent when compared to R-404A. While that is a significant number that still leaves us with a high GWP of R-452A itself.
Yes, R-452A comes in with a GWP of two-thousand one-hundred and forty-one. If you compare that to other refrigerants it is still a VERY high number. Because of this fact I have to say that I do not see this newer HFO refrigerant from Chemours lasting very long. There will come a time in the near future that this refrigerant will be phased out shortly. If you are looking into switching over your 404A system it may make more sense to either wait until a lower GWP alternative comes out or to take a serious look at natural refrigerants out there like R-744 CO2.
Alright folks, with all that being said I’ve talked enough. Let’s get onto the actual pressure chart. When I create these tables I strive to create them as accurate as possible so if you see something that is not right please reach out to me and I will get it corrected as soon as possible.
R-452A XP44 PT Chart
Temp (F) | Temp (C) | Liquid Pressure (PSIG) | Vapor Pressure (PSIG) |
---|---|---|---|
-94 | -70 | -10.84 | -11.61 |
-90.4 | -68 | -10.33 | -11.19 |
-86.8 | -66 | -9.76 | -10.72 |
-83.2 | -64 | -9.14 | -10.21 |
-79.6 | -62 | -8.45 | -9.64 |
-76 | -60 | -7.7 | -9.01 |
-72.4 | -58 | -6.87 | -8.32 |
-68.8 | -56 | -5.97 | -7.56 |
-65.2 | -54 | -4.99 | -6.74 |
-61.6 | -52 | -3.93 | -5.83 |
-58 | -50 | -2.77 | -4.85 |
-54.4 | -48 | -1.52 | -3.78 |
-50.8 | -46 | -0.02 | -2.63 |
-47.2 | -44 | 1.3 | -1.37 |
-43.6 | -42 | 2.88 | -0.02 |
-40 | -40 | 4.57 | 1.45 |
-36.4 | -38 | 6.39 | 3.02 |
-32.8 | -36 | 8.35 | 4.71 |
-29.2 | -34 | 10.44 | 6.53 |
-25.6 | -32 | 12.67 | 8.48 |
-22 | -30 | 15.06 | 10.56 |
-18.4 | -28 | 17.6 | 12.79 |
-14.8 | -26 | 20.3 | 15.17 |
-11.2 | -24 | 23.18 | 17.71 |
-7.6 | -22 | 26.23 | 20.41 |
-4 | -20 | 29.47 | 23.28 |
-0.4 | -18 | 32.9 | 26.33 |
3.2 | -16 | 36.53 | 29.57 |
6.8 | -14 | 40.37 | 33 |
10.4 | -12 | 44.42 | 36.62 |
14 | -10 | 48.69 | 40.46 |
17.6 | -8 | 53.19 | 44.51 |
21.2 | -6 | 57.93 | 48.79 |
24.8 | -4 | 62.91 | 53.3 |
28.4 | -2 | 68.14 | 58.04 |
32 | 0 | 73.63 | 63.04 |
35.6 | 2 | 79.39 | 68.29 |
39.2 | 4 | 85.42 | 73.82 |
42.8 | 6 | 91.74 | 79.61 |
46.4 | 8 | 98.35 | 85.68 |
50 | 10 | 105.26 | 92.05 |
53.6 | 12 | 112.48 | 98.72 |
57.2 | 14 | 120.02 | 105.7 |
60.8 | 16 | 127.88 | 113.01 |
64.4 | 18 | 136.08 | 120.64 |
68 | 20 | 144.61 | 128.61 |
71.6 | 22 | 153.51 | 136.94 |
75.2 | 24 | 162.76 | 145.62 |
78.8 | 26 | 172.38 | 154.69 |
82.4 | 28 | 182.38 | 164.14 |
86 | 30 | 192.76 | 173.97 |
89.6 | 32 | 203.55 | 184.22 |
93.2 | 34 | 214.75 | 194.89 |
96.8 | 36 | 226.36 | 205.99 |
100.4 | 38 | 238.38 | 217.53 |
104 | 40 | 250.85 | 229.54 |
107.6 | 42 | 263.77 | 242.02 |
111.2 | 44 | 277.14 | 254.98 |
114.8 | 46 | 290.99 | 268.45 |
118.4 | 48 | 305.3 | 282.45 |
122 | 50 | 320.1 | 296.97 |
125.6 | 52 | 335.41 | 312.05 |
129.2 | 54 | 351.22 | 327.73 |
132.8 | 56 | 367.56 | 344 |
136.4 | 58 | 384.42 | 360.89 |
140 | 60 | 401.84 | 378.44 |
143.6 | 62 | 419.82 | 396.69 |
147.2 | 64 | 438.35 | 415.67 |
150.8 | 66 | 457.46 | 435.44 |
154.4 | 68 | 477.15 | 456.07 |
158 | 70 | 497.41 | 477.64 |