# 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.

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: