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.