R-32 PT Chart
A2L GWP 675Pure refrigerant (Difluoromethane). HFC.
About R-32
R-32 is a single-component HFC that makes up half of R-410A. Daikin and several other manufacturers use it straight in mini-splits and, increasingly, ducted systems, because it has a GWP of 675 and better heat transfer than R-410A. It has no glide, so one pressure column applies to both superheat and subcooling, but it runs slightly higher pressure and higher discharge temperatures than R-410A and is classified A2L.
Saturation pressures at typical operating points, taken from the table below:
- Evaporator (AC, 40°F): 121.0 PSIG
- Condensing (110°F): 374.9 PSIG
The table covers -80°F to 165°F in 5°F steps. Below about -61°F the saturation pressure is below atmospheric, so gauges read in vacuum (shown in blue in the table).
R-32 Pressure-Temperature Graph
R-32 Saturation Pressure Table
Blue values indicate vacuum (below atmospheric pressure).
| °F | °C | PSIG | PSIA | kPa | bar |
|---|---|---|---|---|---|
| -80 | -62.2 | -6.4 | 8.31 | 57.3 | 0.573 |
| -75 | -59.4 | -5.0 | 9.72 | 67.0 | 0.67 |
| -70 | -56.7 | -3.4 | 11.3 | 77.9 | 0.779 |
| -65 | -53.9 | -1.6 | 13.09 | 90.3 | 0.903 |
| -60 | -51.1 | 0.4 | 15.11 | 104.1 | 1.041 |
| -55 | -48.3 | 2.7 | 17.35 | 119.7 | 1.197 |
| -50 | -45.6 | 5.2 | 19.86 | 136.9 | 1.369 |
| -45 | -42.8 | 8.0 | 22.65 | 156.1 | 1.561 |
| -40 | -40.0 | 11.0 | 25.73 | 177.4 | 1.774 |
| -35 | -37.2 | 14.4 | 29.14 | 200.9 | 2.009 |
| -30 | -34.4 | 18.2 | 32.89 | 226.7 | 2.267 |
| -25 | -31.7 | 22.3 | 37.0 | 255.1 | 2.551 |
| -20 | -28.9 | 26.8 | 41.51 | 286.2 | 2.862 |
| -15 | -26.1 | 31.7 | 46.43 | 320.1 | 3.201 |
| -10 | -23.3 | 37.1 | 51.8 | 357.1 | 3.571 |
| -5 | -20.6 | 42.9 | 57.63 | 397.3 | 3.973 |
| 0 | -17.8 | 49.3 | 63.95 | 440.9 | 4.409 |
| 5 | -15.0 | 56.1 | 70.79 | 488.1 | 4.881 |
| 10 | -12.2 | 63.5 | 78.18 | 539.0 | 5.39 |
| 15 | -9.4 | 71.4 | 86.14 | 593.9 | 5.939 |
| 20 | -6.7 | 80.0 | 94.71 | 653.0 | 6.53 |
| 25 | -3.9 | 89.2 | 103.92 | 716.5 | 7.165 |
| 30 | -1.1 | 99.1 | 113.79 | 784.6 | 7.846 |
| 35 | 1.7 | 109.7 | 124.35 | 857.4 | 8.574 |
| 40 | 4.4 | 121.0 | 135.65 | 935.3 | 9.353 |
| 45 | 7.2 | 133.0 | 147.7 | 1018.3 | 10.183 |
| 50 | 10.0 | 145.8 | 160.54 | 1106.9 | 11.069 |
| 55 | 12.8 | 159.5 | 174.21 | 1201.2 | 12.012 |
| 60 | 15.6 | 174.0 | 188.74 | 1301.3 | 13.013 |
| 65 | 18.3 | 189.5 | 204.17 | 1407.7 | 14.077 |
| 70 | 21.1 | 205.8 | 220.52 | 1520.5 | 15.205 |
| 75 | 23.9 | 223.2 | 237.85 | 1639.9 | 16.399 |
| 80 | 26.7 | 241.5 | 256.18 | 1766.3 | 17.663 |
| 85 | 29.4 | 260.9 | 275.56 | 1899.9 | 18.999 |
| 90 | 32.2 | 281.3 | 296.02 | 2041.0 | 20.41 |
| 95 | 35.0 | 302.9 | 317.61 | 2189.8 | 21.898 |
| 100 | 37.8 | 325.7 | 340.37 | 2346.8 | 23.468 |
| 105 | 40.6 | 349.6 | 364.34 | 2512.1 | 25.121 |
| 110 | 43.3 | 374.9 | 389.58 | 2686.1 | 26.861 |
| 115 | 46.1 | 401.4 | 416.13 | 2869.1 | 28.691 |
| 120 | 48.9 | 429.3 | 444.04 | 3061.5 | 30.615 |
| 125 | 51.7 | 458.7 | 473.37 | 3263.8 | 32.638 |
| 130 | 54.4 | 489.5 | 504.17 | 3476.1 | 34.761 |
| 135 | 57.2 | 521.8 | 536.52 | 3699.1 | 36.991 |
| 140 | 60.0 | 555.8 | 570.47 | 3933.2 | 39.332 |
| 145 | 62.8 | 591.4 | 606.1 | 4178.9 | 41.789 |
| 150 | 65.6 | 628.8 | 643.51 | 4436.9 | 44.369 |
| 155 | 68.3 | 668.1 | 682.8 | 4707.7 | 47.077 |
| 160 | 71.1 | 709.4 | 724.09 | 4992.4 | 49.924 |
| 165 | 73.9 | 752.9 | 767.57 | 5292.2 | 52.922 |
Properties
| ASHRAE Designation | 32 |
| Safety Classification | A2L (mildly flammable) |
| GWP (AR4, 100-yr) | 675 |
| ODP | 0 |
| Molecular Weight | 52.02 g/mol |
| Boiling Point (1 atm) | -61.0°F / -51.7°C |
| Critical Temperature | 172.6°F / 78.1°C |
| Critical Pressure | 838.7 psia / 57.83 bar |
| Category | HFC |
Common Applications
- Residential AC
- Heat pumps
- Component of R-410A
Frequently Asked Questions
What pressure should R-32 be at 70°F?
At 70°F, R-32 has a saturation pressure of 205.8 PSIG (220.5 PSIA), slightly higher than R-410A (201.7 PSIG). R-32 is a single-component refrigerant with no temperature glide, making servicing straightforward.
What equipment uses R-32 refrigerant?
R-32 is the primary refrigerant in modern mini-split systems from Daikin, Mitsubishi, and other manufacturers. It is also used in many new ducted split systems. R-32 has a GWP of 675 — about 68% lower than R-410A's 2088.
Is R-32 safe to use?
R-32 is classified A2L (mildly flammable, low burning velocity). It requires A2L-rated service equipment and follows ASHRAE 15 safety guidelines. R-32 should not be used as a replacement refrigerant in R-410A equipment — systems must be designed for R-32.