R-427A
Quaternary HFC blend (15% R-32 / 25% R-125 / 10% R-143a / 50% R-134a). Branded as Arkema Forane 427A. ASHRAE A1, GWP 2138. Marketed as 'simple retrofit' from R-22 — works with any of mineral, alkylbenzene, or POE oils.
Lower toxicity (Occupational Exposure Limit ≥ 400 ppm). No flame propagation in air at standard atmospheric pressure and 60°C. R-134a, R-22, R-410A, R-404A, R-744 (CO2) are A1.
- Flammability
- None (no flame propagation)
- Toxicity
- Lower (OEL ≥ 400 ppm)
Classification per ANSI/ASHRAE Standard 34-2022. See full reference.
Saturation pressure-temperature curve
Saturation values from CoolProp 7.2.0 R427A.mix. Operating pressure on a running system differs — see the operating-pressure references for in-use values.
R-427A PT chart PDF — printable saturation table
Looking for the R-427A PT chart PDF for shop reference? The complete pressure-temperature saturation table is below — every 1° increment from −40°F to 150°F (or to the refrigerant's critical temperature). Use the Print / Save as PDF button in the table header to download a clean, table-only PDF (the rest of the page is hidden from the print output). Important service temperatures (normal boiling point, freezing point of water, residential AC evap and condenser targets) are tinted and tagged in the table for at-a-glance shop reference.
R-427A PT Chart — Pressure-Temperature Saturation Table
1° increments · Source: CoolProp 7.2.0 / manufacturer datasheet · hvacptcharts.com
| Temp (°F) | Bubble (PSIG) | Dew (PSIG) | Glide (PSI) |
|---|---|---|---|
| -40°F | 2.2 | -2.5 | 4.8 |
| -39°F | 2.7 | -2.2 | 4.8 |
| -38°F | 3.1 | -1.8 | 4.9 |
| -37°F | 3.6 | -1.5 | 5.0 |
| -36°F | 4.0 | -1.1 | 5.1 |
| -35°F | 4.5 | -0.7 | 5.2 |
| -34°F | 5.0 | -0.3 | 5.3 |
| -33°F | 5.5 | 0.1 | 5.4 |
| -32°F | 6.0 | 0.5 | 5.5 |
| -31°F | 6.5 | 0.9 | 5.6 |
| -30°F | 7.0 | 1.3 | 5.7 |
| -29°F | 7.6 | 1.7 | 5.8 |
| -28°F | 8.1 | 2.2 | 5.9 |
| -27°F | 8.7 | 2.6 | 6.0 |
| -26°F | 9.2 | 3.1 | 6.2 |
| -25°F | 9.8 | 3.5 | 6.3 |
| -24°F | 10.4 | 4.0 | 6.4 |
| -23°F | 11.0 | 4.5 | 6.5 |
| -22°F | 11.6 | 5.0 | 6.6 |
| -21°F | 12.2 | 5.5 | 6.7 |
| -20°F | 12.8 | 6.0 | 6.8 |
| -19°F | 13.5 | 6.5 | 7.0 |
| -18°F | 14.1 | 7.1 | 7.1 |
| -17°F | 14.8 | 7.6 | 7.2 |
| -16°F | 15.5 | 8.2 | 7.3 |
| -15°F | 16.2 | 8.8 | 7.4 |
| -14°F | 16.9 | 9.3 | 7.5 |
| -13°F | 17.6 | 9.9 | 7.7 |
| -12°F | 18.3 | 10.5 | 7.8 |
| -11°F | 19.1 | 11.1 | 7.9 |
| -10°F | 19.8 | 11.8 | 8.0 |
| -9°F | 20.6 | 12.4 | 8.2 |
| -8°F | 21.3 | 13.0 | 8.3 |
| -7°F | 22.1 | 13.7 | 8.4 |
| -6°F | 22.9 | 14.4 | 8.6 |
| -5°F | 23.7 | 15.1 | 8.7 |
| -4°F | 24.6 | 15.8 | 8.8 |
| -3°F | 25.4 | 16.5 | 9.0 |
| -2°F | 26.3 | 17.2 | 9.1 |
| -1°F | 27.1 | 17.9 | 9.2 |
| 0°F | 28.0 | 18.7 | 9.4 |
| 1°F | 28.9 | 19.4 | 9.5 |
| 2°F | 29.8 | 20.2 | 9.6 |
| 3°F | 30.8 | 21.0 | 9.8 |
| 4°F | 31.7 | 21.8 | 9.9 |
| 5°F | 32.7 | 22.6 | 10.1 |
| 6°F | 33.6 | 23.4 | 10.2 |
| 7°F | 34.6 | 24.3 | 10.3 |
| 8°F | 35.6 | 25.1 | 10.5 |
| 9°F | 36.6 | 26.0 | 10.6 |
| 10°F | 37.7 | 26.9 | 10.8 |
| 11°F | 38.7 | 27.8 | 10.9 |
| 12°F | 39.8 | 28.7 | 11.1 |
| 13°F | 40.9 | 29.7 | 11.2 |
| 14°F | 42.0 | 30.6 | 11.4 |
| 15°F | 43.1 | 31.6 | 11.5 |
| 16°F | 44.2 | 32.5 | 11.7 |
| 17°F | 45.4 | 33.5 | 11.8 |
| 18°F | 46.5 | 34.6 | 12.0 |
| 19°F | 47.7 | 35.6 | 12.1 |
| 20°F | 48.9 | 36.6 | 12.3 |
| 21°F | 50.1 | 37.7 | 12.5 |
| 22°F | 51.4 | 38.8 | 12.6 |
| 23°F | 52.6 | 39.9 | 12.8 |
| 24°F | 53.9 | 41.0 | 12.9 |
| 25°F | 55.2 | 42.1 | 13.1 |
| 26°F | 56.5 | 43.2 | 13.3 |
| 27°F | 57.8 | 44.4 | 13.4 |
| 28°F | 59.2 | 45.6 | 13.6 |
| 29°F | 60.5 | 46.8 | 13.8 |
| 30°F | 61.9 | 48.0 | 13.9 |
| 31°F | 63.3 | 49.2 | 14.1 |
| 32°FH₂O freeze | 64.7 | 50.5 | 14.2 |
| 33°F | 66.2 | 51.8 | 14.4 |
| 34°F | 67.6 | 53.1 | 14.6 |
| 35°F | 69.1 | 54.4 | 14.8 |
| 36°F | 70.6 | 55.7 | 14.9 |
| 37°F | 72.1 | 57.0 | 15.1 |
| 38°F | 73.7 | 58.4 | 15.3 |
| 39°F | 75.2 | 59.8 | 15.4 |
| 40°FAC evap target | 76.8 | 61.2 | 15.6 |
| 41°F | 78.4 | 62.6 | 15.8 |
| 42°F | 80.0 | 64.1 | 16.0 |
| 43°F | 81.7 | 65.6 | 16.1 |
| 44°F | 83.3 | 67.0 | 16.3 |
| 45°F | 85.0 | 68.6 | 16.5 |
| 46°F | 86.7 | 70.1 | 16.6 |
| 47°F | 88.5 | 71.7 | 16.8 |
| 48°F | 90.2 | 73.2 | 17.0 |
| 49°F | 92.0 | 74.8 | 17.2 |
| 50°F | 93.8 | 76.4 | 17.4 |
| 51°F | 95.6 | 78.1 | 17.5 |
| 52°F | 97.5 | 79.8 | 17.7 |
| 53°F | 99.3 | 81.4 | 17.9 |
| 54°F | 101.2 | 83.1 | 18.1 |
| 55°F | 103.1 | 84.9 | 18.3 |
| 56°F | 105.0 | 86.6 | 18.4 |
| 57°F | 107.0 | 88.4 | 18.6 |
| 58°F | 109.0 | 90.2 | 18.8 |
| 59°F | 111.0 | 92.0 | 19.0 |
| 60°F | 113.0 | 93.9 | 19.2 |
| 61°F | 115.1 | 95.8 | 19.3 |
| 62°F | 117.2 | 97.7 | 19.5 |
| 63°F | 119.3 | 99.6 | 19.7 |
| 64°F | 121.4 | 101.5 | 19.9 |
| 65°F | 123.5 | 103.5 | 20.0 |
| 66°F | 125.7 | 105.5 | 20.2 |
| 67°F | 127.9 | 107.5 | 20.4 |
| 68°F | 130.2 | 109.6 | 20.6 |
| 69°F | 132.4 | 111.6 | 20.8 |
| 70°FRoom T | 134.7 | 113.7 | 21.0 |
| 71°F | 137.0 | 115.9 | 21.1 |
| 72°F | 139.3 | 118.0 | 21.3 |
| 73°F | 141.7 | 120.2 | 21.5 |
| 74°F | 144.1 | 122.4 | 21.7 |
| 75°F | 146.5 | 124.7 | 21.8 |
| 76°F | 148.9 | 126.9 | 22.0 |
| 77°F | 151.4 | 129.2 | 22.2 |
| 78°F | 153.9 | 131.5 | 22.4 |
| 79°F | 156.4 | 133.9 | 22.6 |
| 80°F | 159.0 | 136.2 | 22.8 |
| 81°F | 161.6 | 138.6 | 22.9 |
| 82°F | 164.2 | 141.1 | 23.1 |
| 83°F | 166.8 | 143.5 | 23.3 |
| 84°F | 169.5 | 146.0 | 23.5 |
| 85°F | 172.2 | 148.5 | 23.6 |
| 86°F | 174.9 | 151.1 | 23.8 |
| 87°F | 177.7 | 153.7 | 24.0 |
| 88°F | 180.4 | 156.3 | 24.2 |
| 89°F | 183.3 | 158.9 | 24.3 |
| 90°F | 186.1 | 161.6 | 24.5 |
| 91°F | 189.0 | 164.3 | 24.7 |
| 92°F | 191.9 | 167.0 | 24.8 |
| 93°F | 194.8 | 169.8 | 25.0 |
| 94°F | 197.8 | 172.6 | 25.2 |
| 95°FAHRI design ambient | 200.8 | 175.4 | 25.3 |
| 96°F | 203.8 | 178.3 | 25.5 |
| 97°F | 206.8 | 181.2 | 25.7 |
| 98°F | 209.9 | 184.1 | 25.8 |
| 99°F | 213.1 | 187.1 | 26.0 |
| 100°F | 216.2 | 190.0 | 26.2 |
| 101°F | 219.4 | 193.1 | 26.3 |
| 102°F | 222.6 | 196.1 | 26.5 |
| 103°F | 225.9 | 199.2 | 26.6 |
| 104°F | 229.1 | 202.3 | 26.8 |
| 105°F | 232.5 | 205.5 | 27.0 |
| 106°F | 235.8 | 208.7 | 27.1 |
| 107°F | 239.2 | 211.9 | 27.3 |
| 108°F | 242.6 | 215.2 | 27.4 |
| 109°F | 246.1 | 218.5 | 27.5 |
| 110°FTypical cond saturation | 249.5 | 221.9 | 27.7 |
| 111°F | 253.1 | 225.2 | 27.8 |
| 112°F | 256.6 | 228.7 | 28.0 |
| 113°F | 260.2 | 232.1 | 28.1 |
| 114°F | 263.8 | 235.6 | 28.2 |
| 115°F | 267.5 | 239.1 | 28.4 |
| 116°F | 271.2 | 242.7 | 28.5 |
| 117°F | 274.9 | 246.3 | 28.6 |
| 118°F | 278.7 | 249.9 | 28.8 |
| 119°F | 282.5 | 253.6 | 28.9 |
| 120°F | 286.3 | 257.3 | 29.0 |
| 121°F | 290.2 | 261.1 | 29.1 |
| 122°F | 294.1 | 264.9 | 29.2 |
| 123°F | 298.1 | 268.7 | 29.3 |
| 124°F | 302.0 | 272.6 | 29.4 |
| 125°F | 306.1 | 276.5 | 29.5 |
| 126°F | 310.1 | 280.5 | 29.6 |
| 127°F | 314.2 | 284.5 | 29.7 |
| 128°F | 318.4 | 288.5 | 29.8 |
| 129°F | 322.5 | 292.6 | 29.9 |
| 130°F | 326.8 | 296.8 | 30.0 |
| 131°F | 331.0 | 300.9 | 30.1 |
| 132°F | 335.3 | 305.2 | 30.1 |
| 133°F | 339.6 | 309.4 | 30.2 |
| 134°F | 344.0 | 313.7 | 30.3 |
| 135°F | 348.4 | 318.1 | 30.3 |
| 136°F | 352.9 | 322.5 | 30.4 |
| 137°F | 357.4 | 326.9 | 30.4 |
| 138°F | 361.9 | 331.4 | 30.5 |
| 139°F | 366.5 | 336.0 | 30.5 |
| 140°F | 371.1 | 340.6 | 30.5 |
| 141°F | 375.8 | 345.2 | 30.6 |
| 142°F | 380.4 | 349.9 | 30.6 |
| 143°F | 385.2 | 354.6 | 30.6 |
| 144°F | 390.0 | 359.4 | 30.6 |
| 145°F | 394.8 | 364.2 | 30.6 |
| 146°F | 399.7 | 369.1 | 30.6 |
| 147°F | 404.6 | 374.0 | 30.6 |
| 148°F | 409.6 | 379.0 | 30.5 |
| 149°F | 414.6 | 384.1 | 30.5 |
| 150°F | 419.6 | 389.1 | 30.4 |
| Temp (°C) | Bubble (kPa) | Dew (kPa) | Glide (kPa) |
|---|---|---|---|
| -40°C | 15 | -17 | 33 |
| -39°C | 21 | -13 | 34 |
| -38°C | 27 | -9 | 35 |
| -37°C | 33 | -4 | 36 |
| -36°C | 39 | 1 | 38 |
| -35°C | 45 | 6 | 39 |
| -34°C | 51 | 11 | 40 |
| -33°C | 58 | 17 | 41 |
| -32°C | 65 | 22 | 43 |
| -31°C | 73 | 28 | 44 |
| -30°C | 80 | 35 | 46 |
| -29°C | 88 | 41 | 47 |
| -28°C | 96 | 47 | 48 |
| -27°C | 104 | 54 | 50 |
| -26°C | 112 | 61 | 51 |
| -25°C | 121 | 68 | 53 |
| -24°C | 130 | 76 | 54 |
| -23°C | 140 | 84 | 56 |
| -22°C | 149 | 92 | 58 |
| -21°C | 159 | 100 | 59 |
| -20°C | 169 | 109 | 61 |
| -19°C | 180 | 117 | 62 |
| -18°C | 191 | 127 | 64 |
| -17°C | 202 | 136 | 66 |
| -16°C | 213 | 146 | 67 |
| -15°C | 225 | 156 | 69 |
| -14°C | 237 | 166 | 71 |
| -13°C | 250 | 177 | 73 |
| -12°C | 263 | 188 | 75 |
| -11°C | 276 | 199 | 77 |
| -10°C | 290 | 211 | 79 |
| -9°C | 303 | 223 | 80 |
| -8°C | 318 | 236 | 82 |
| -7°C | 332 | 248 | 84 |
| -6°C | 348 | 261 | 86 |
| -5°C | 363 | 275 | 88 |
| -4°C | 379 | 289 | 90 |
| -3°C | 395 | 303 | 92 |
| -2°C | 412 | 318 | 94 |
| -1°C | 429 | 333 | 96 |
| 0°CH₂O freeze | 446 | 348 | 98 |
| 1°C | 464 | 364 | 100 |
| 2°C | 483 | 380 | 102 |
| 3°C | 502 | 397 | 105 |
| 4°CAC evap target | 521 | 414 | 107 |
| 5°C | 541 | 432 | 109 |
| 6°C | 561 | 450 | 111 |
| 7°C | 582 | 469 | 113 |
| 8°C | 603 | 488 | 115 |
| 9°C | 625 | 507 | 117 |
| 10°C | 647 | 527 | 120 |
| 11°C | 669 | 548 | 122 |
| 12°C | 693 | 569 | 124 |
| 13°C | 716 | 590 | 126 |
| 14°C | 741 | 612 | 129 |
| 15°C | 765 | 635 | 131 |
| 16°C | 791 | 658 | 133 |
| 17°C | 817 | 681 | 135 |
| 18°C | 843 | 705 | 137 |
| 19°C | 870 | 730 | 140 |
| 20°C | 897 | 755 | 142 |
| 21°CRoom T | 926 | 781 | 144 |
| 22°C | 954 | 808 | 146 |
| 23°C | 984 | 835 | 149 |
| 24°C | 1,013 | 863 | 151 |
| 25°C | 1,044 | 891 | 153 |
| 26°C | 1,075 | 920 | 155 |
| 27°C | 1,107 | 949 | 158 |
| 28°C | 1,139 | 979 | 160 |
| 29°C | 1,172 | 1,010 | 162 |
| 30°C | 1,206 | 1,042 | 164 |
| 31°C | 1,240 | 1,074 | 166 |
| 32°C | 1,275 | 1,107 | 168 |
| 33°C | 1,311 | 1,140 | 171 |
| 34°C | 1,347 | 1,174 | 173 |
| 35°CAHRI design ambient | 1,384 | 1,209 | 175 |
| 36°C | 1,422 | 1,245 | 177 |
| 37°C | 1,460 | 1,281 | 179 |
| 38°C | 1,500 | 1,319 | 181 |
| 39°C | 1,539 | 1,356 | 183 |
| 40°C | 1,580 | 1,395 | 185 |
| 41°C | 1,621 | 1,435 | 187 |
| 42°C | 1,663 | 1,475 | 189 |
| 43°CTypical cond saturation | 1,706 | 1,516 | 190 |
| 44°C | 1,750 | 1,558 | 192 |
| 45°C | 1,794 | 1,600 | 194 |
| 46°C | 1,839 | 1,644 | 196 |
| 47°C | 1,885 | 1,688 | 197 |
| 48°C | 1,932 | 1,733 | 199 |
| 49°C | 1,979 | 1,779 | 200 |
| 50°C | 2,028 | 1,826 | 202 |
| 51°C | 2,077 | 1,874 | 203 |
| 52°C | 2,127 | 1,923 | 204 |
| 53°C | 2,178 | 1,973 | 205 |
| 54°C | 2,230 | 2,023 | 206 |
| 55°C | 2,282 | 2,075 | 207 |
| 56°C | 2,336 | 2,128 | 208 |
| 57°C | 2,390 | 2,181 | 209 |
| 58°C | 2,445 | 2,236 | 210 |
| 59°C | 2,502 | 2,291 | 210 |
| 60°C | 2,559 | 2,348 | 211 |
| 61°C | 2,617 | 2,406 | 211 |
| 62°C | 2,676 | 2,465 | 211 |
| 63°C | 2,736 | 2,525 | 211 |
| 64°C | 2,796 | 2,586 | 211 |
| 65°C | 2,858 | 2,648 | 210 |
Full saturation values at 1° increments — toggle between °F / PSIG and °C / kPa. Use Print / Save as PDF for laminated shop reference, or download the CSV / JSON below for use in other tools. R-427A PT chart data: CoolProp 7.2.0 (REFPROP-compatible Helmholtz EOS) or manufacturer datasheet, validated against AHRI Standard 700-2019.
At a glance
Chemistry
Lubricant compatibility
Marketed as 'simple retrofit' from R-22 — designed to work with any of MO/AB/POE oils.
Blend composition
- R-3215.0%
- R-12525.0%
- R-143a10.0%
- R-134a50.0%
Trade names
- Forane 427AArkema
Common applications
- R-22 retrofit (commercial AC, heat pumps, supermarket refrigeration)
- Compatible with mineral oil systems
Properties
- Boiling point (1 atm)-43.0°C / -45.4°F
- Critical pointNo single point — blend critical locus
- Molar mass90.44 g/mol
- Temperature glide10.4°F
- ODP0
- GWP (AR5, 100-yr)2138
- GWP (AR6, 100-yr)2370
What is R-427A?
R-427A is Arkema's four-component R-22 retrofit blend, developed in the 2000s alongside the other R-22 retrofit families (Chemours' ISCEON line, Honeywell's Genetron MO99). The composition includes 15% R-32 — the higher-volatility HFC component that contributes capacity — alongside the R-125, R-143a, and R-134a components that provide the operating envelope and non-flammability.
Unlike the hydrocarbon-aided R-22 retrofits (R-417A, R-422A, R-422D, R-438A), R-427A achieves mineral-oil compatibility through blend composition rather than a hydrocarbon additive. Arkema markets this as oil-flexibility — R-427A works with MO, AB, or POE — so the retrofit doesn't require an oil change but POE can be added if preferred.
Where R-427A is used
- R-22 retrofit (residential AC, heat pumps, light commercial)
- Medium-temperature commercial refrigeration (R-22 retrofit)
- Some compressor manufacturers' R-22 service literature names R-427A as a preferred retrofit
Regulatory & phase-down status
R-427A's GWP of 2138 is above the EPA AIM Act 700 threshold for new equipment. For new installations R-427A is not the choice; for R-22 retrofit work it remains commercially available.
GWP-wise, R-427A is the lower-GWP option among the major R-22 retrofit family (R-407C at 1774 is lower, but requires POE oil change). The trade-offs across the R-22 retrofit family are: R-407C (lowest GWP, requires oil change), R-417A/R-421A/R-422D/R-427A/R-438A (moderate-to-higher GWP, mineral-oil compatible, no oil change).
Service notes
Compatible with mineral oil (MO), alkylbenzene (AB), and POE oils. For R-22 retrofits the existing mineral oil stays in the system — no oil change is required. R-427A has moderate temperature glide (~6-7°F at typical evaporator pressures); TXV operation may require attention after retrofit.
Temperature glide
R-427A is a zeotropic blend: at constant pressure it boils across a temperature range rather than at a single point. This affects EXV sizing, charge measurement, and superheat measurement. Use the dew curve for superheat, bubble curve for subcooling.
Operating cycle
Phase-down timeline
No phase-down milestones documented for R-427A in this build. This may mean: (a) no regulatory phase-down currently published; (b) the refrigerant has local regulatory schedules not yet transcribed into the site dataset; or (c) it is a specialty refrigerant outside the main regulatory frameworks. For authoritative current status, consult the EPA AIM Act allocations (40 CFR Part 84), EU F-Gas Regulation 517/2014 + 2024/573, and the relevant national implementations of the Kigali Amendment.
Global warming potential, in context
R-22 retrofit blends
Retrofit and replacement paths
R-427A replaces
Replacements for R-427A
Frequently asked
›How does R-427A compare to other R-22 retrofit blends?
R-427A has the lowest GWP (2138) among the major mineral-oil-compatible R-22 retrofit blends. R-417A (2346), R-421A (2630), R-422D (2729), R-438A (2265) are similar in function but higher GWP. R-407C (1774) is lower GWP than R-427A but requires POE oil change. R-427A's appeal is the combination of mineral-oil compatibility (no oil change) and the lowest GWP in that subset.
›What is the normal operating pressure of R-427A?
Close to R-22 across the envelope. At 95°F outdoor ambient on a residential AC retrofitted from R-22 to R-427A, expect roughly 65-78 PSIG suction and 235-275 PSIG discharge — within a few PSI of R-22's operating envelope. The 15% R-32 content gives R-427A slightly higher capacity than the hydrocarbon-aided retrofits.
›What lubricant does R-427A use?
Compatible with mineral oil (MO), alkylbenzene (AB), and POE. For R-22 retrofits the existing mineral oil stays in the system. R-427A doesn't include a hydrocarbon component — the mineral-oil compatibility comes from the blend chemistry itself.
›Does R-427A have temperature glide?
Yes — about 6-7°F at typical evaporator pressures. Use the dew curve for superheat measurement. TXV systems may require retuning after retrofit; EXV systems handle the glide automatically.
›Is R-427A the same as Forane 427A?
Yes. Forane 427A is Arkema's commercial brand name; R-427A is the ASHRAE 34 designation. Forane is Arkema's refrigerant brand family — Forane 22, Forane 410A, Forane 134a, etc., spanning the HFC and HCFC product lines.
›Should I use R-427A or R-407C for an R-22 retrofit?
Trade-off between operational simplicity and GWP. R-407C requires POE oil change but has lower GWP (1774 vs 2138). R-427A works with the existing mineral oil but has higher GWP. For service-cost-sensitive retrofits R-427A is the simpler choice; for systems expected to remain in service long enough for the GWP difference to matter, R-407C is the cleaner choice.
›What's the GWP of R-427A?
2138 (IPCC AR5, mass-weighted from R-32, R-125, R-143a, R-134a components). This is the lowest among the mineral-oil-compatible R-22 retrofit blends, though still above the AIM Act 700 threshold for new equipment.