R-290 PT chart
Saturation pressures for R-290 from -40 °F to 150 °F, computed from reference equations of state[5]. Propane is a single compound, so liquid and vapor pressures are equal at a given temperature and there is no glide.
| Temp (°F) | Liquid / bubble (psig) | Vapor / dew (psig) |
|---|---|---|
| -40 | 1.4 | 1.4 |
| -35 | 3.4 | 3.4 |
| -30 | 5.7 | 5.7 |
| -25 | 8.1 | 8.1 |
| -20 | 10.7 | 10.7 |
| -15 | 13.6 | 13.6 |
| -10 | 16.7 | 16.7 |
| -5 | 20.1 | 20.1 |
| 0 | 23.7 | 23.7 |
| 5 | 27.6 | 27.6 |
| 10 | 31.8 | 31.8 |
| 15 | 36.3 | 36.3 |
| 20 | 41.1 | 41.1 |
| 25 | 46.3 | 46.3 |
| 30 | 51.8 | 51.8 |
| 35 | 57.7 | 57.7 |
| 40 | 63.9 | 63.9 |
| 45 | 70.6 | 70.6 |
| 50 | 77.6 | 77.6 |
| 55 | 85.1 | 85.1 |
| 60 | 93.0 | 93.0 |
| 65 | 101.4 | 101.4 |
| 70 | 110.2 | 110.2 |
| 75 | 119.5 | 119.5 |
| 80 | 129.3 | 129.3 |
| 85 | 139.7 | 139.7 |
| 90 | 150.5 | 150.5 |
| 95 | 161.9 | 161.9 |
| 100 | 173.9 | 173.9 |
| 105 | 186.5 | 186.5 |
| 110 | 199.6 | 199.6 |
| 115 | 213.4 | 213.4 |
| 120 | 227.8 | 227.8 |
| 125 | 242.9 | 242.9 |
| 130 | 258.7 | 258.7 |
| 135 | 275.1 | 275.1 |
| 140 | 292.3 | 292.3 |
| 145 | 310.2 | 310.2 |
| 150 | 328.9 | 328.9 |
Use the vapor (dew) column to check superheat at the suction line. Use the liquid (bubble) column to check subcooling at the liquid line and for charging. R-290 has no glide, so one pressure column serves both charging and superheat checks. R-290 values are computed, not transcribed; see Sources.
How to read it: measure suction pressure at the service port, find that pressure in the vapor column, and the temperature beside it is the saturation temperature. Suction line temperature minus saturation temperature is superheat. For subcooling, use the liquid column and liquid line pressure, then subtract the liquid line temperature from the saturation temperature.
About this data
Computed with CoolProp 8.0.0 predefined mixture models (Helmholtz-energy equations of state; Bell, Wronski, Quoilin, Lemort 2014, Ind. Eng. Chem. Res. 53(6), doi:10.1021/ie4033999).
Full R-290 reference: regulatory status, replacements, and equipment rated for it, on the R-290 page.
Updated