R404A PT Chart: Pressure Temperature Chart For -49°F To +150°F

R404A is one of the most commonly used refrigerants. This class of refrigerants (HFCs like R404A or R134A) were introduced in the 90s and 2000s to replace the harmful CFCs. Of course, as with every refrigerant, you need to use the R404A PT chart to get an idea of what kind of pressure you are working with at certain temperatures.

404R pressure temperature chart is quite simple to understand. This is a table that tells you precisely what the pressure of R404A is at a certain temperature. At the low end, the pressure of 404A is 0.9 psig. At the high end, the pressure of 404A is 456.8 psig. We are, of course, talking about 404A liquid pressure.

Example: What is the pressure of R404A at 85°F? Just check the R404A PT chart below and you will see that the pressure of 404A liquid at 85°F is 189.5 psig and the pressure of 404A vapor is 187.5 psig at the same temperature.

r404a pressure at 100 degree temperature
We use gauge meter to measure the pressure of R404A refrigerant at different temperatures.

Here it’s worth noting that the 404A PT chart includes both liquid and vapor (gas) pressures. The difference between these two pressures is quite insignificant and in practice, we usually just take the pressure of the 404A refrigerant in liquid state for various calculations.

Since we use a gauge meter to measure 404A pressures, the unit we use is not psi (pounds per square inch) but psig (pounds per square inch gauge). That’s how we can measure what is the R404A pressure on a 70-degree, 80-degree, 90-degree, and 100-degree day (you will find all of these examples under the chart).

Note: For on-site use, we include a printable R404A PT chart in PDF form at the end of the article.

Here is the full R404A PT chart from the low end (-49°F) to the high end (150°F):

404A Pressure Temperature Chart

Temperature (°F): Temperature (°C): 404A Liquid Pressure (psig): 404A Vapor Pressure (psig):
-49°F -45.0°C 0.9 psig 0.3 psig
-48°F -44.4°C 1.3 psig 0.7 psig
-47°F -43.9°C 1.7 psig 1.2 psig
-46°F -43.3°C 2.1 psig 1.6 psig
-45°F -42.8°C 2.6 psig 2.0 psig
-44°F -42.2°C 3.0 psig 2.4 psig
-43°F -41.7°C 3.5 psig 2.9 psig
-42°F -41.1°C 4.0 psig 3.4 psig
-41°F -40.6°C 4.4 psig 3.8 psig
-40°F -40.0°C 4.9 psig 4.3 psig
-39°F -39.4°C 5.4 psig 4.8 psig
-38°F -38.9°C 5.9 psig 5.3 psig
-37°F -38.3°C 6.4 psig 5.8 psig
-36°F -37.8°C 7.0 psig 6.3 psig
-35°F -37.2°C 7.5 psig 6.8 psig
-34°F -36.7°C 8.0 psig 7.4 psig
-33°F -36.1°C 8.6 psig 7.9 psig
-32°F -35.6°C 9.2 psig 8.5 psig
-31°F -35.0°C 9.7 psig 9.0 psig
-30°F -34.4°C 10.3 psig 9.6 psig
-29°F -33.9°C 10.9 psig 10.2 psig
-28°F -33.3°C 11.5 psig 10.8 psig
-27°F -32.8°C 12.2 psig 11.4 psig
-26°F -32.2°C 12.8 psig 12.0 psig
-25°F -31.7°C 13.4 psig 12.7 psig
-24°F -31.1°C 14.1 psig 13.3 psig
-23°F -30.6°C 14.8 psig 14.0 psig
-22°F -30.0°C 15.4 psig 14.6 psig
-21°F -29.4°C 16.1 psig 15.3 psig
-20°F -28.9°C 16.8 psig 16.0 psig
-19°F -28.3°C 17.5 psig 16.7 psig
-18°F -27.8°C 18.3 psig 17.4 psig
-17°F -27.2°C 19.0 psig 18.2 psig
-16°F -26.7°C 19.8 psig 18.9 psig
-15°F -26.1°C 20.5 psig 19.7 psig
-14°F -25.6°C 21.3 psig 20.4 psig
-13°F -25.0°C 22.1 psig 21.2 psig
-12°F -24.4°C 22.9 psig 22.0 psig
-11°F -23.9°C 23.7 psig 22.8 psig
-10°F -23.3°C 24.6 psig 23.6 psig
-9°F -22.8°C 25.4 psig 24.5 psig
-8°F -22.2°C 26.3 psig 25.3 psig
-7°F -21.7°C 27.1 psig 26.2 psig
-6°F -21.1°C 28.0 psig 27.0 psig
-5°F -20.6°C 28.9 psig 27.9 psig
-4°F -20.0°C 29.8 psig 28.8 psig
-3°F -19.4°C 30.8 psig 29.8 psig
-2°F -18.9°C 31.7 psig 30.7 psig
-1°F -18.3°C 32.7 psig 31.6 psig
0°F -17.8°C 33.7 psig 32.6 psig
1°F -17.2°C 34.7 psig 33.6 psig
2°F -16.7°C 35.7 psig 34.6 psig
3°F -16.1°C 36.7 psig 35.6 psig
4°F -15.6°C 37.7 psig 36.6 psig
5°F -15.0°C 38.8 psig 37.7 psig
6°F -14.4°C 39.8 psig 38.7 psig
7°F -13.9°C 40.9 psig 39.8 psig
8°F -13.3°C 42.0 psig 40.9 psig
9°F -12.8°C 43.1 psig 42.0 psig
10°F -12.2°C 44.3 psig 43.1 psig
11°F -11.7°C 45.4 psig 44.3 psig
12°F -11.1°C 46.6 psig 45.4 psig
13°F -10.6°C 47.8 psig 46.6 psig
14°F -10.0°C 49.0 psig 47.8 psig
15°F -9.4°C 50.2 psig 49.0 psig
16°F -8.9°C 51.5 psig 50.2 psig
17°F -8.3°C 52.7 psig 51.5 psig
18°F -7.8°C 54.0 psig 52.7 psig
19°F -7.2°C 55.3 psig 54.0 psig
20°F -6.7°C 56.6 psig 55.3 psig
21°F -6.1°C 57.9 psig 56.6 psig
22°F -5.6°C 59.3 psig 58.0 psig
23°F -5.0°C 60.6 psig 59.3 psig
24°F -4.4°C 62.0 psig 60.7 psig
25°F -3.9°C 63.4 psig 62.1 psig
26°F -3.3°C 64.8 psig 63.5 psig
27°F -2.8°C 66.3 psig 64.9 psig
28°F -2.2°C 67.8 psig 66.4 psig
29°F -1.7°C 69.2 psig 67.8 psig
30°F -1.1°C 70.7 psig 69.3 psig
31°F -0.6°C 72.3 psig 70.8 psig
32°F 0°C 73.8 psig 72.4 psig
33°F 0.6°C 75.4 psig 73.9 psig
34°F 1.1°C 77.0 psig 75.5 psig
35°F 1.7°C 78.6 psig 77.1 psig
36°F 2.2°C 80.2 psig 78.7 psig
37°F 2.8°C 81.8 psig 80.3 psig
38°F 3.3°C 83.5 psig 82.0 psig
39°F 3.9°C 85.2 psig 83.7 psig
40°F 4.4°C 86.9 psig 85.4 psig
41°F 5.0°C 88.6 psig 87.1 psig
42°F 5.6°C 90.4 psig 88.8 psig
43°F 6.1°C 92.2 psig 90.6 psig
44°F 6.7°C 94.0 psig 92.4 psig
45°F 7.2°C 95.8 psig 94.2 psig
46°F 7.8°C 97.6 psig 96.0 psig
47°F 8.3°C 99.5 psig 97.9 psig
48°F 8.9°C 101.4 psig 99.8 psig
49°F 9.4°C 103.3 psig 101.7 psig
50°F 10.0°C 105.3 psig 103.6 psig
51°F 10.6°C 107.2 psig 105.6 psig
52°F 11.1°C 109.2 psig 107.6 psig
53°F 11.7°C 111.2 psig 109.6 psig
54°F 12.2°C 113.3 psig 111.6 psig
55°F 12.8°C 115.3 psig 113.6 psig
56°F 13.3°C 117.4 psig 115.7 psig
57°F 13.9°C 119.5 psig 117.8 psig
58°F 14.4°C 121.7 psig 119.9 psig
59°F 15.0°C 123.8 psig 122.1 psig
60°F 15.6°C 126.0 psig 124.2 psig
61°F 16.1°C 128.2 psig 126.4 psig
62°F 16.7°C 130.5 psig 128.7 psig
63°F 17.2°C 132.7 psig 130.9 psig
64°F 17.8°C 135.0 psig 133.2 psig
65°F 18.3°C 137.3 psig 135.5 psig
66°F 18.9°C 139.7 psig 137.8 psig
67°F 19.4°C 142.0 psig 140.2 psig
68°F 20.0°C 144.4 psig 142.6 psig
69°F 20.6°C 146.9 psig 145.0 psig
70°F 21.1°C 149.3 psig 147.4 psig
71°F 21.7°C 149.3 psig 147.4 psig
72°F 22.2°C 154.3 psig 152.4 psig
73°F 22.8°C 156.8 psig 154.9 psig
74°F 23.3°C 159.4 psig 157.5 psig
75°F 23.9°C 162.0 psig 160.1 psig
76°F 24.4°C 164.6 psig 162.7 psig
77°F 25.0°C 167.3 psig 165.3 psig
78°F 25.6°C 170.0 psig 168.0 psig
79°F 26.1°C 172.7 psig 170.7 psig
80°F 26.7°C 175.4 psig 173.4 psig
81°F 27.2°C 178.2 psig 176.2 psig
82°F 27.8°C 181.0 psig 179.0 psig
83°F 28.3°C 183.8 psig 181.8 psig
84°F 29.4°C 186.7 psig 184.7 psig
85°F 30.0°C 189.5 psig 187.5 psig
86°F 30.6°C 192.5 psig 190.4 psig
87°F 31.1°C 195.4 psig 193.4 psig
88°F 31.7°C 198.4 psig 196.4 psig
89°F 31.7°C 201.4 psig 199.4 psig
90°F 32.2°C 204.5 psig 202.4 psig
91°F 32.8°C 207.6 psig 205.5 psig
92°F 33.3°C 210.7 psig 208.6 psig
93°F 33.9°C 213.8 psig 211.7 psig
94°F 34.4°C 217.0 psig 214.9 psig
95°F 35.0°C 220.2 psig 218.1 psig
96°F 35.6°C 223.4 psig 221.4 psig
97°F 36.1°C 226.7 psig 224.6 psig
98°F 36.7°C 230.0 psig 227.9 psig
99°F 37.2°C 233.4 psig 231.3 psig
100°F 37.8°C 236.8 psig 234.2 psig
105°F 40.6°C 254.2 psig 252.1 psig
110°F 43.3°C 272.5 psig 270.4 psig
115°F 46.1°C 291.8 psig 289.6 psig
120°F 48.9°C 312.1 psig 309.9 psig
125°F 51.7°C 333.3 psig 331.2 psig
130°F 54.4°C 355.7 psig 353.5 psig
135°F 57.2°C 379.1 psig 377.0 psig
140°F 60.0°C 403.7 psig 401.7 psig
145°F 62.8°C 429.6 psig 427.7 psig
150°F 65.6°C 456.8 psig 455.1 psig

Let’s look at some cases to illustrate how you can use this PT chart for R404A:

R404A Pressures On A 70-Degree Day?

If you check the chart above, you can see that the pressure of the liquid R404A refrigerant is 149.3 psig. If you are measuring the pressure of a 404A gas (vapor), your gauge meter should read 147.4 psig on a 70-degree day. The difference between liquid and vapor pressure here is 1.7 psig.

R404A Pressures On A 80-Degree Day?

If you check the chart above, you can see that the pressure of the liquid R404A refrigerant is 175.4 psig. If you are measuring the pressure of a 404A gas (vapor), your gauge meter should read 173.4 psig on an 80-degree day. The difference between liquid and vapor pressure here is 1.7 psig.

R404A Pressures On A 90-Degree Day?

If you check the chart above, you can see that the pressure of the liquid R404A refrigerant is 204.5 psig. If you are measuring the pressure of a 404A gas (vapor), your gauge meter should read 202.4 psig on a 90-degree day. The difference between liquid and vapor pressure here is 1.9 psig.

R404A Pressures On A 100-Degree Day?

If you check the chart above, you can see that the pressure of the liquid R404A refrigerant is 236.8 psig. If you are measuring the pressure of a 404A gas (vapor), your gauge meter should read 234.2 psig on a 100-degree day. The difference between liquid and vapor pressure here is 2.6 psig.

R404A PT Chart PDF (Printable PDF For On-Site Use)

As promised, you can get the printable PDF version of the R404A PT chart here if you need it on-site:

Hopefully, this illustrates the correlation between pressure and temperature for an R404A refrigerant. You can check similar PT charts for:

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