R448a PT Chart: -49°F To 150°F Temperatures (+ Chart PDF)

R448a PT chart is quite useful in HVAC. It tells you what is the pressure of R488a liquid and vapor refrigerant from -49°F to 150°F. Inversely, you can also tell the temperature of R488a refrigerant if you know the pressures (from 0.7 psig to 462.8 psig). Further on, you will find an online R448a pressure temperature chart as well as a printable R448a PT chart in PDF form you can take with you.

R448a (CAS name: Solistice N-40) is a blend of 4 HFC and HFO refrigerants. It is comprised of R32 (24.3%), R125 (24.7%), 134a (25.7%), 1234zf (25.3%) and it has a boiling point of -45.9°C (-50.62°F).

You can use the 448a PT chart for several different HVAC tasks, including:

  • Telling what are the pressures of 448a on 65-degree, 70-degree, 75-degree, 80-degree, 85-degree, 90-degree, 95-degree, 100-degree days, and so on. We include 8 examples of how high are the pressures of R448a on 65-100 degree days.
  • Identifying if the refrigerant in HVACR systems or reusable grey bottles are actually R448a or not.
  • Differentiating between 488a and other refrigerants, based on the pressure temperature chart.
  • Using the 488a vapor pressures to determine the superheat and total superheat and, if needed, charge more freon if 448a superheat is high or remove freon (recover it) if the 488a superheat is low.
  • Using the 488a liquid pressures to determine the subcooling and, if needed, charge or recover freon is the 448a set lines.

Note: You always have to measure both pressure and temperature when the HVAC unit (AC, refrigerator) is off and equalized. When equalized (mixture of liquid and vapor at the same temperature), the pressures of 448a on high and low sides are the same (measured at service ports). If you measure the pressure when the HVAC unit is running, the saturated state is found only at the evaporator and the condenser.

Here is the full R488a PT chart, followed by those 8 examples, and a printable PDF version you can take with you on the job:

448a Pressure Temperature Chart

Temperature (°F): Temperature (°C): 448a Liquid Pressure (psig): 448a Vapor Pressure (psig):
-49°F -45.0°C 0.7 psig 0.0 psig
-48°F -44.4°C 1.1 psig 0.0 psig
-47°F -43.9°C 1.5 psig 0.0 psig
-46°F -43.3°C 1.9 psig 0.0 psig
-45°F -42.8°C 2.4 psig 0.0 psig
-44°F -42.2°C 2.8 psig 0.0 psig
-43°F -41.7°C 3.3 psig 0.0 psig
-42°F -41.1°C 3.8 psig 0.0 psig
-41°F -40.6°C 4.2 psig 0.0 psig
-40°F -40.0°C 4.7 psig 0.0 psig
-39°F -39.4°C 5.2 psig 0.2 psig
-38°F -38.9°C 5.7 psig 0.6 psig
-37°F -38.3°C 6.2 psig 1.1 psig
-36°F -37.8°C 6.8 psig 1.5 psig
-35°F -37.2°C 7.3 psig 1.9 psig
-34°F -36.7°C 7.9 psig 2.4 psig
-33°F -36.1°C 8.4 psig 2.8 psig
-32°F -35.6°C 9.0 psig 3.3 psig
-31°F -35.0°C 9.6 psig 3.7 psig
-30°F -34.4°C 10.2 psig 4.2 psig
-29°F -33.9°C 10.8 psig 4.7 psig
-28°F -33.3°C 11.4 psig 5.2 psig
-27°F -32.8°C 12.0 psig 5.7 psig
-26°F -32.2°C 12.6 psig 6.3 psig
-25°F -31.7°C 13.3 psig 6.8 psig
-24°F -31.1°C 13.9 psig 7.3 psig
-23°F -30.6°C 14.6 psig 7.9 psig
-22°F -30.0°C 15.3 psig 8.4 psig
-21°F -29.4°C 16.0 psig 9.0 psig
-20°F -28.9°C 16.7 psig 9.6 psig
-19°F -28.3°C 17.4 psig 10.2 psig
-18°F -27.8°C 18.2 psig 10.8 psig
-17°F -27.2°C 18.9 psig 11.2 psig
-16°F -26.7°C 19.7 psig 12.1 psig
-15°F -26.1°C 20.4 psig 12.7 psig
-14°F -25.6°C 21.2 psig 13.4 psig
-13°F -25.0°C 22.0 psig 14.0 psig
-12°F -24.4°C 22.8 psig 14.7 psig
-11°F -23.9°C 23.7 psig 15.4 psig
-10°F -23.3°C 24.5 psig 16.1 psig
-9°F -22.8°C 25.4 psig 16.8 psig
-8°F -22.2°C 26.2 psig 17.6 psig
-7°F -21.7°C 27.1 psig 18.3 psig
-6°F -21.1°C 28.0 psig 19.1 psig
-5°F -20.6°C 28.9 psig 19.8 psig
-4°F -20.0°C 29.9 psig 20.6 psig
-3°F -19.4°C 30.8 psig 21.4 psig
-2°F -18.9°C 31.8 psig 22.2 psig
-1°F -18.3°C 32.7 psig 23.1 psig
0°F -17.8°C 33.7 psig 23.9 psig
1°F -17.2°C 34.7 psig 24.8 psig
2°F -16.7°C 35.8 psig 25.6 psig
3°F -16.1°C 36.8 psig 26.5 psig
4°F -15.6°C 37.8 psig 27.4 psig
5°F -15.0°C 38.9 psig 28.3 psig
6°F -14.4°C 40.0 psig 29.3 psig
7°F -13.9°C 41.1 psig 30.2 psig
8°F -13.3°C 42.2 psig 31.2 psig
9°F -12.8°C 43.4 psig 32.2 psig
10°F -12.2°C 44.5 psig 33.1 psig
11°F -11.7°C 45.7 psig 34.2 psig
12°F -11.1°C 46.9 psig 35.2 psig
13°F -10.6°C 48.1 psig 36.2 psig
14°F -10.0°C 49.3 psig 37.3 psig
15°F -9.4°C 50.6 psig 38.4 psig
16°F -8.9°C 51.8 psig 39.4 psig
17°F -8.3°C 53.1 psig 40.6 psig
18°F -7.8°C 54.4 psig 41.7 psig
19°F -7.2°C 55.7 psig 42.8 psig
20°F -6.7°C 57.1 psig 44.0 psig
21°F -6.1°C 58.4 psig 45.2 psig
22°F -5.6°C 59.8 psig 46.4 psig
23°F -5.0°C 61.2 psig 47.6 psig
24°F -4.4°C 62.6 psig 48.8 psig
25°F -3.9°C 64.0 psig 50.1 psig
26°F -3.3°C 65.5 psig 51.3 psig
27°F -2.8°C 66.9 psig 52.6 psig
28°F -2.2°C 68.4 psig 53.9 psig
29°F -1.7°C 70.0 psig 55.3 psig
30°F -1.1°C 71.5 psig 56.6 psig
31°F -0.6°C 73.0 psig 58.0 psig
32°F 0°C 74.6 psig 59.4 psig
33°F 0.6°C 76.2 psig 60.8 psig
34°F 1.1°C 77.8 psig 62.2 psig
35°F 1.7°C 79.5 psig 63.7 psig
36°F 2.2°C 81.1 psig 65.1 psig
37°F 2.8°C 82.8 psig 66.6 psig
38°F 3.3°C 84.5 psig 68.1 psig
39°F 3.9°C 86.3 psig 69.7 psig
40°F 4.4°C 88.0 psig 71.2 psig
41°F 5.0°C 89.8 psig 72.8 psig
42°F 5.6°C 91.6 psig 74.4 psig
43°F 6.1°C 93.4 psig 76.0 psig
44°F 6.7°C 95.2 psig 77.7 psig
45°F 7.2°C 97.1 psig 79.3 psig
46°F 7.8°C 99.0 psig 81.0 psig
47°F 8.3°C 100.9 psig 82.7 psig
48°F 8.9°C 102.9 psig 84.5 psig
49°F 9.4°C 104.8 psig 86.2 psig
50°F 10.0°C 106.8 psig 88.0 psig
51°F 10.6°C 108.8 psig 89.8 psig
52°F 11.1°C 110.8 psig 91.7 psig
53°F 11.7°C 112.9 psig 93.5 psig
54°F 12.2°C 115.0 psig 95.4 psig
55°F 12.8°C 117.1 psig 97.3 psig
56°F 13.3°C 119.2 psig 99.2 psig
57°F 13.9°C 121.4 psig 101.2 psig
58°F 14.4°C 123.6 psig 103.2 psig
59°F 15.0°C 125.8 psig 105.2 psig
60°F 15.6°C 128.0 psig 107.2 psig
61°F 16.1°C 130.3 psig 109.3 psig
62°F 16.7°C 132.6 psig 111.3 psig
63°F 17.2°C 134.9 psig 113.4 psig
64°F 17.8°C 137.3 psig 115.6 psig
65°F 18.3°C 139.6 psig 117.7 psig
66°F 18.9°C 142.0 psig 119.9 psig
67°F 19.4°C 144.5 psig 122.1 psig
68°F 20.0°C 146.9 psig 124.4 psig
69°F 20.6°C 149.4 psig 126.7 psig
70°F 21.1°C 151.9 psig 129.0 psig
71°F 21.7°C 154.4 psig 131.3 psig
72°F 22.2°C 157.0 psig 133.7 psig
73°F 22.8°C 159.6 psig 136.0 psig
74°F 23.3°C 162.2 psig 138.5 psig
75°F 23.9°C 164.9 psig 140.9 psig
76°F 24.4°C 167.6 psig 143.4 psig
77°F 25.0°C 170.3 psig 145.9 psig
78°F 25.6°C 173.0 psig 148.4 psig
79°F 26.1°C 175.8 psig 151.0 psig
80°F 26.7°C 178.6 psig 153.6 psig
81°F 27.2°C 181.4 psig 156.2 psig
82°F 27.8°C 184.3 psig 158.8 psig
83°F 28.3°C 187.2 psig 161.5 psig
84°F 29.4°C 190.1 psig 164.3 psig
85°F 30.0°C 193.1 psig 167.0 psig
86°F 30.6°C 196.1 psig 169.8 psig
87°F 31.1°C 199.1 psig 172.6 psig
88°F 31.7°C 202.2 psig 175.4 psig
89°F 31.7°C 205.2 psig 178.3 psig
90°F 32.2°C 208.4 psig 181.2 psig
91°F 32.8°C 211.5 psig 184.2 psig
92°F 33.3°C 214.7 psig 187.2 psig
93°F 33.9°C 217.9 psig 190.2 psig
94°F 34.4°C 221.2 psig 193.2 psig
95°F 35.0°C 224.4 psig 196.3 psig
96°F 35.6°C 227.7 psig 199.4 psig
97°F 36.1°C 231.1 psig 202.6 psig
98°F 36.7°C 234.5 psig 205.8 psig
99°F 37.2°C 237.9 psig 209.0 psig
100°F 37.8°C 241.3 psig 212.3 psig
105°F 40.6°C 297.4 psig 265.7 psig
110°F 43.3°C 277.8 psig 246.9 psig
115°F 46.1°C 291.8 psig 289.6 psig
120°F 48.9°C 317.9 psig 285.6 psig
125°F 51.7°C 339.4 psig 306.5 psig
130°F 54.4°C 362.0 psig 328.5 psig
135°F 57.2°C 385.5 psig 351.8 psig
140°F 60.0°C 410.2 psig 376.3 psig
145°F 62.8°C 435.9 psig 402.1 psig
150°F 65.6°C 462.8 psig 429.4 psig

As always, the pressure of 448a rises with the temperature. If you want to figure out if you have a 448a refrigerant in the line set or in a bottle at certain temperatures, you can consult this PT chart.

Here are just a few examples of how to use the 448a pressure temperature chart given the outdoor temperature:

Example 1: What Are 448a Pressures On A 65-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on a 65-degree day is 139.6 psig.

Similarly, we can see that the vapor pressure of 448a on a 65-degree is 117.7 psig.

Example 2: What Are 448a Pressures On A 70-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on a 70-degree day is 151.9 psig.

Similarly, we can see that the vapor pressure of 448a on a 70-degree is 129.0 psig.

Example 3: What Are 448a Pressures On A 75-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on a 75-degree day is 164.9 psig.

Similarly, we can see that the vapor pressure of 448a on a 75-degree is 140.9 psig.

Example 4: What Are 448a Pressures On A 80-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on an 80-degree day is 178.6 psig.

Similarly, we can see that the vapor pressure of 448a on an 80-degree is 153.6 psig.

Example 5: What Are 448a Pressures On A 85-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on an 85-degree day is 193.1 psig.

Similarly, we can see that the vapor pressure of 448a on an 85-degree is 167.0 psig.

Example 6: What Are 448a Pressures On A 90-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on a 90-degree day is 208.4 psig.

Similarly, we can see that the vapor pressure of 448a on a 90-degree is 181.2 psig.

Example 7: What Are 448a Pressures On A 95-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on a 95-degree day is 224.4 psig.

Similarly, we can see that the vapor pressure of 448a on a 95-degree is 196.3 psig.

Example 8: What Are 448a Pressures On A 100-Degree Day?

From the PT chart, we can read that the pressure of liquid 448a on a 100-degree day is 241.3 psig.

Similarly, we can see that the vapor pressure of 448a on a 100-degree is 212.3 psig.

448a Pressure Temperature Chart PDF

As promised, you can get the printable PDF version of the 448a PT chart here if you need it on-site. Here is the full chart you can freely download and take with you:

 

With this printable PT chart, we hope that you will be able to use a 448aPT chart without any problems.

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