PT chart · ASHRAE A1
R-744 PT Chart
R-744 pressure–temperature chart in psig and °F/°C. CO2: transcritical refrigeration and heat pumps.
Vacuum readings are shown in inches of mercury (″ Hg) below atmospheric pressure.
| °F | °C | Pressure, psig |
|---|---|---|
| -50 | -45.6 | 103.4 |
| -45 | -42.8 | 116.6 |
| -40 | -40.0 | 131.0 |
| -35 | -37.2 | 146.5 |
| -30 | -34.4 | 163.1 |
| -25 | -31.7 | 181.0 |
| -20 | -28.9 | 200.2 |
| -15 | -26.1 | 220.8 |
| -10 | -23.3 | 242.7 |
| -5 | -20.6 | 266.1 |
| 0 | -17.8 | 291.0 |
| 5 | -15.0 | 317.6 |
| 10 | -12.2 | 345.7 |
| 15 | -9.4 | 375.6 |
| 20 | -6.7 | 407.2 |
| 25 | -3.9 | 440.7 |
| 30 | -1.1 | 476.1 |
| 35 | 1.7 | 513.4 |
| 40 | 4.4 | 552.9 |
| 45 | 7.2 | 594.5 |
| 50 | 10.0 | 638.3 |
| 55 | 12.8 | 684.5 |
| 60 | 15.6 | 733.1 |
| 65 | 18.3 | 784.2 |
| 70 | 21.1 | 838.1 |
| 75 | 23.9 | 894.9 |
| 80 | 26.7 | 954.9 |
| 85 | 29.4 | 1018.4 |
Source: NIST Chemistry WebBook, SRD 69, saturation properties. Converted from absolute pressure (psia) to psig. Reference only; verify against the equipment manufacturer's data.
The whole job, on your phone
HVAC Charge: Superheat & PT
Look up R-744 offline in the field and get superheat, subcooling and a charge call in seconds. See what's inside.