PT chart · ASHRAE A1
R-427A PT Chart
R-427A pressure–temperature chart in psig and °F/°C. R-22 retrofit for AC and refrigeration.
R-427A is a zeotropic blend with temperature glide, so the chart has two columns: use the vapor (dew) column for superheat and the liquid (bubble) column for subcooling.
Vacuum readings are shown in inches of mercury (″ Hg) below atmospheric pressure.
| °F | °C | Liquid (bubble), psig | Vapor (dew), psig |
|---|---|---|---|
| -50 | -45.6 | 3.5″ Hg | 11.4″ Hg |
| -45 | -42.8 | 0.1 | 8.4″ Hg |
| -40 | -40.0 | 2.2 | 5.1″ Hg |
| -35 | -37.2 | 4.5 | 1.5″ Hg |
| -30 | -34.4 | 7.0 | 1.3 |
| -25 | -31.7 | 9.7 | 3.5 |
| -20 | -28.9 | 12.8 | 6.0 |
| -15 | -26.1 | 16.1 | 8.7 |
| -10 | -23.3 | 19.7 | 11.7 |
| -5 | -20.6 | 23.6 | 15.0 |
| 0 | -17.8 | 27.9 | 18.7 |
| 5 | -15.0 | 32.6 | 22.6 |
| 10 | -12.2 | 37.6 | 26.9 |
| 15 | -9.4 | 43.0 | 31.5 |
| 20 | -6.7 | 48.8 | 36.6 |
| 25 | -3.9 | 55.0 | 42.1 |
| 30 | -1.1 | 61.7 | 48.0 |
| 35 | 1.7 | 68.9 | 54.3 |
| 40 | 4.4 | 76.6 | 61.2 |
| 45 | 7.2 | 84.8 | 68.5 |
| 50 | 10.0 | 93.6 | 76.4 |
| 55 | 12.8 | 102.9 | 84.8 |
| 60 | 15.6 | 112.8 | 93.8 |
| 65 | 18.3 | 123.3 | 103.4 |
| 70 | 21.1 | 134.4 | 113.7 |
| 75 | 23.9 | 146.2 | 124.6 |
| 80 | 26.7 | 158.6 | 136.1 |
| 85 | 29.4 | 171.8 | 148.4 |
| 90 | 32.2 | 185.7 | 161.5 |
| 95 | 35.0 | 200.3 | 175.3 |
| 100 | 37.8 | 215.8 | 189.9 |
| 105 | 40.6 | 232.0 | 205.4 |
| 110 | 43.3 | 249.1 | 221.7 |
| 115 | 46.1 | 267.0 | 238.9 |
| 120 | 48.9 | 285.8 | 257.1 |
| 125 | 51.7 | 305.5 | 276.3 |
| 130 | 54.4 | 326.2 | 296.5 |
| 135 | 57.2 | 347.8 | 317.8 |
| 140 | 60.0 | 370.5 | 340.3 |
| 145 | 62.8 | 394.1 | 363.9 |
| 150 | 65.6 | 418.9 | 388.8 |
Source: Arkema Forane® Pressure-Temperature Wall Chart, Americas (2019). Reference only; verify against the equipment manufacturer's data.
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