PT chart · ASHRAE A1
R-409A PT Chart
R-409A pressure–temperature chart in psig and °F/°C. Refrigeration (R-12 retrofit).
R-409A 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 | 12.2″ Hg | 18.7″ Hg |
| -45 | -42.8 | 9.6″ Hg | 16.9″ Hg |
| -40 | -40.0 | 6.7″ Hg | 14.8″ Hg |
| -35 | -37.2 | 3.5″ Hg | 12.5″ Hg |
| -30 | -34.4 | 0.0 | 9.9″ Hg |
| -25 | -31.7 | 1.9 | 7.0″ Hg |
| -20 | -28.9 | 4.0 | 3.8″ Hg |
| -15 | -26.1 | 6.3 | 0.2″ Hg |
| -10 | -23.3 | 8.8 | 1.8 |
| -5 | -20.6 | 11.6 | 4.0 |
| 0 | -17.8 | 14.6 | 6.3 |
| 5 | -15.0 | 17.8 | 8.8 |
| 10 | -12.2 | 21.3 | 11.6 |
| 15 | -9.4 | 25.1 | 14.7 |
| 20 | -6.7 | 29.2 | 18.0 |
| 25 | -3.9 | 33.6 | 21.6 |
| 30 | -1.1 | 38.4 | 25.5 |
| 35 | 1.7 | 43.4 | 29.7 |
| 40 | 4.4 | 48.9 | 34.2 |
| 45 | 7.2 | 54.7 | 39.1 |
| 50 | 10.0 | 60.9 | 44.3 |
| 55 | 12.8 | 67.4 | 49.9 |
| 60 | 15.6 | 74.5 | 55.9 |
| 65 | 18.3 | 81.9 | 62.3 |
| 70 | 21.1 | 89.8 | 69.1 |
| 75 | 23.9 | 98.2 | 76.4 |
| 80 | 26.7 | 107.0 | 84.2 |
| 85 | 29.4 | 116.4 | 92.5 |
| 90 | 32.2 | 126.2 | 101.2 |
| 95 | 35.0 | 136.6 | 110.5 |
| 100 | 37.8 | 147.6 | 120.3 |
| 105 | 40.6 | 159.1 | 130.7 |
| 110 | 43.3 | 171.2 | 141.7 |
| 115 | 46.1 | 183.9 | 153.3 |
| 120 | 48.9 | 197.2 | 165.6 |
| 125 | 51.7 | 211.1 | 178.5 |
| 130 | 54.4 | 225.7 | 192.0 |
| 135 | 57.2 | 241.0 | 206.3 |
| 140 | 60.0 | 257.0 | 221.3 |
| 145 | 62.8 | 273.7 | 237.1 |
| 150 | 65.6 | 291.1 | 253.6 |
Source: Arkema Forane® Pressure-Temperature Wall Chart, Americas (2019). Reference only; verify against the equipment manufacturer's data.
The whole job, on your phone
HVAC Charge: Superheat & PT
Look up R-409A offline in the field and get superheat, subcooling and a charge call in seconds. See what's inside.