R502 pressure–temperature chart
R502 is a near-azeotropic blend. Its normal boiling point is -44.3 °C. At the AHRI 540 air-conditioning rating point — 7.2 °C evaporating, 54.4 °C condensing — the saturation pressures are 6.91 and 22.81 bar, a pressure ratio of 3.30. As a near-azeotropic blend it evaporates and condenses over a range of temperatures at one pressure — a glide of 0.2 K at 0.0 °C — so the dew line (where the last liquid boils off) and the bubble line (where the first vapour forms) are both tabulated. Superheat is measured up from the dew temperature and subcooling down from the bubble temperature; a map's 8.3 K of subcooling is 8.3 K under the bubble line, not the dew line, and this solver reads it so.
Units: SI · US customary
Saturation table, -75 to 70 °C
| Dew °C | Bubble °C | Glide K | kPa abs | bar abs | psig | hfg kJ/kg | ρ liquid kg/m³ | ρ vapour kg/m³ |
|---|---|---|---|---|---|---|---|---|
| -75 | -75.8 | 0.8 | 18.4 | 0.184 | -12.0 | 188.2 | 1585 | 1.26 |
| -70 | -70.7 | 0.7 | 25.3 | 0.253 | -11.0 | 185.9 | 1570 | 1.70 |
| -65 | -65.7 | 0.7 | 34.2 | 0.342 | -9.7 | 183.6 | 1555 | 2.25 |
| -60 | -60.6 | 0.6 | 45.5 | 0.455 | -8.1 | 181.3 | 1539 | 2.93 |
| -55 | -55.6 | 0.6 | 59.6 | 0.596 | -6.1 | 178.9 | 1523 | 3.77 |
| -50 | -50.5 | 0.5 | 77.0 | 0.770 | -3.5 | 176.5 | 1507 | 4.78 |
| -45 | -45.5 | 0.5 | 98.1 | 0.981 | -0.5 | 174.1 | 1491 | 6.00 |
| -40 | -40.4 | 0.4 | 123.5 | 1.235 | 3.2 | 171.6 | 1475 | 7.45 |
| -35 | -35.4 | 0.4 | 153.8 | 1.538 | 7.6 | 169.0 | 1458 | 9.15 |
| -30 | -30.3 | 0.3 | 189.5 | 1.895 | 12.8 | 166.3 | 1441 | 11.14 |
| -25 | -25.3 | 0.3 | 231.3 | 2.313 | 18.9 | 163.6 | 1424 | 13.45 |
| -20 | -20.3 | 0.3 | 279.8 | 2.798 | 25.9 | 160.7 | 1407 | 16.12 |
| -15 | -15.2 | 0.2 | 335.7 | 3.357 | 34.0 | 157.8 | 1389 | 19.19 |
| -10 | -10.2 | 0.2 | 399.6 | 3.996 | 43.3 | 154.7 | 1370 | 22.70 |
| -5 | -5.2 | 0.2 | 472.2 | 4.722 | 53.8 | 151.5 | 1351 | 26.69 |
| 0 | -0.2 | 0.2 | 554.3 | 5.543 | 65.7 | 148.2 | 1332 | 31.23 |
| 5 | 4.9 | 0.1 | 646.6 | 6.466 | 79.1 | 144.7 | 1312 | 36.37 |
| 10 | 9.9 | 0.1 | 749.8 | 7.498 | 94.1 | 141.1 | 1292 | 42.19 |
| 15 | 14.9 | 0.1 | 864.8 | 8.648 | 110.7 | 137.3 | 1271 | 48.76 |
| 20 | 19.9 | 0.1 | 992.3 | 9.923 | 129.2 | 133.3 | 1249 | 56.19 |
| 25 | 24.9 | 0.1 | 1133.2 | 11.332 | 149.7 | 129.0 | 1226 | 64.59 |
| 30 | 29.9 | 0.1 | 1288.3 | 12.883 | 172.2 | 124.5 | 1202 | 74.10 |
| 35 | 35.0 | 0.0 | 1458.5 | 14.585 | 196.8 | 119.8 | 1177 | 84.91 |
| 40 | 40.0 | 0.0 | 1644.8 | 16.448 | 223.9 | 114.7 | 1150 | 97.23 |
| 45 | 45.0 | 0.0 | 1848.2 | 18.482 | 253.4 | 109.1 | 1122 | 111.38 |
| 50 | 50.0 | 0.0 | 2069.9 | 20.699 | 285.5 | 103.1 | 1092 | 127.76 |
| 55 | 55.0 | 0.0 | 2310.9 | 23.109 | 320.5 | 96.5 | 1059 | 146.97 |
| 60 | 60.0 | 0.0 | 2572.8 | 25.728 | 358.5 | 89.2 | 1022 | 169.90 |
| 65 | 65.0 | 0.0 | 2857.2 | 28.572 | 399.7 | 80.7 | 980 | 198.03 |
| 70 | 70.0 | 0.0 | 3166.2 | 31.662 | 444.5 | 70.7 | 931 | 234.09 |
Pressures are absolute in kPa and bar, gauge in psig (at 101.325 kPa atmospheric); hfg is the latent heat of vaporisation at the dew pressure; densities are saturated liquid and saturated vapour. Computed with CoolProp 8.0.0, the open-source property library the solver runs on, sampled every 0.5 K and printed every 5 K — the same tables the builder reads when it solves a circuit on R502.
R502 compressors in the catalog
1 compressor map runs on R502, a page with its AHRI 540 / EN 12900 map across the published envelope, and selectable in the builder. Read it at your own evaporating and condensing temperatures →
- Embraco — 1 map
Open the R502 chart in the app — the pressure–temperature line drawn, readable at any point, with a compressor's envelope over it — or open the builder and draw a circuit on R502: the solver finds its evaporating and condensing temperatures from the coils and the compressor's map.