R-454B pressure-temperature chart
R-454B saturation pressures from -40 °F to 150 °F, in gauge pressure (psig), with both the liquid (bubble) and vapor (dew) values. At 40 °F, R-454B vapor saturates at 107.0 psig; at 105 °F, the liquid saturates at 322.8 psig.
R-454B PT chart (psig, every 5 °F)
| °F | °C | Liquid (bubble) psig | Vapor (dew) psig |
|---|---|---|---|
| -40 | -40.0 | 9.5 | 8.4 |
| -35 | -37.2 | 12.7 | 11.4 |
| -30 | -34.4 | 16.2 | 14.8 |
| -25 | -31.7 | 20.1 | 18.5 |
| -20 | -28.9 | 24.3 | 22.6 |
| -15 | -26.1 | 28.9 | 27.0 |
| -10 | -23.3 | 33.9 | 31.8 |
| -5 | -20.6 | 39.4 | 37.0 |
| 0 | -17.8 | 45.3 | 42.7 |
| 5 | -15.0 | 51.7 | 48.8 |
| 10 | -12.2 | 58.5 | 55.4 |
| 15 | -9.4 | 66.0 | 62.6 |
| 20 | -6.7 | 73.9 | 70.3 |
| 25 | -3.9 | 82.5 | 78.5 |
| 30 | -1.1 | 91.7 | 87.4 |
| 35 | 1.7 | 101.5 | 96.9 |
| 40 | 4.4 | 112.0 | 107.0 |
| 45 | 7.2 | 123.1 | 117.8 |
| 50 | 10.0 | 135.0 | 129.3 |
| 55 | 12.8 | 147.7 | 141.6 |
| 60 | 15.6 | 161.1 | 154.6 |
| 65 | 18.3 | 175.4 | 168.5 |
| 70 | 21.1 | 190.5 | 183.1 |
| 75 | 23.9 | 206.5 | 198.7 |
| 80 | 26.7 | 223.4 | 215.2 |
| 85 | 29.4 | 241.2 | 232.6 |
| 90 | 32.2 | 260.0 | 251.0 |
| 95 | 35.0 | 279.9 | 270.4 |
| 100 | 37.8 | 300.8 | 290.9 |
| 105 | 40.6 | 322.8 | 312.5 |
| 110 | 43.3 | 345.9 | 335.2 |
| 115 | 46.1 | 370.2 | 359.1 |
| 120 | 48.9 | 395.7 | 384.3 |
| 125 | 51.7 | 422.4 | 410.8 |
| 130 | 54.4 | 450.5 | 438.7 |
| 135 | 57.2 | 479.9 | 468.0 |
| 140 | 60.0 | 510.7 | 498.8 |
| 145 | 62.8 | 543.0 | 531.3 |
| 150 | 65.6 | 576.8 | 565.4 |
Need a reading between rows, or your elevation corrected? Use the tool above: type a temperature or a pressure and it fills in the other.
About R-454B
R-454B is a blend of R-32 and R-1234yf and one of the main replacements for R-410A in new residential and light-commercial AC and heat pumps. It is classed A2L, mildly flammable, so follow the manufacturer's A2L procedures and use tools and recovery equipment rated for A2L refrigerants.
It runs at slightly lower pressure than R-410A (about 107 against 118 psig at 40 °F) and has a temperature glide of about 2 to 3 °F, which is why this chart has two columns.
How to read a PT chart
A pressure-temperature chart gives the saturation temperature: the temperature at which the refrigerant boils or condenses at a given pressure. Inside the evaporator and condenser, where liquid and vapor are both present, pressure and temperature are locked together, so one gauge reading tells you the other.
- Find your pressure on the chart (or type it into the tool) and read the saturation temperature next to it.
- Superheat = suction line temperature − saturation temperature at suction pressure. Use the superheat calculator.
- Subcooling = saturation temperature at liquid line pressure − liquid line temperature. Use the subcooling calculator.
- Gauges read psig, pressure above the air around you. Charts are built for sea level (14.696 psi). At 5,000 ft your gauge reads about 2.5 psi high against the chart; enter your elevation in the tool and it corrects for it.
Liquid and vapor columns: temperature glide
R-454B is a blend whose components boil at slightly different temperatures, so at the same pressure it starts boiling (the bubble point, liquid column) a little colder than it finishes condensing (the dew point, vapor column). That difference is the glide. Use the vapor (dew) value for superheat and the liquid (bubble) value for subcooling. The tool does this for you.
Working on refrigerant circuits?
Opening the refrigerant circuit on stationary equipment using the refrigerants on this page requires EPA Section 608 certification, and suppliers can only sell you most refrigerants if you have it. See how to get EPA 608 certified or take the free EPA 608 practice tests.
Where the numbers come from
Saturation pressures for R-454B: Chemours, Thermodynamic Properties of Opteon XL41 (R-454B) (based on NIST REFPROP 10). Converted to gauge pressure at sea level (psig = psia − 14.696); below 0 psig the chart shows inches of mercury of vacuum. Values are for pure refrigerant: air, moisture or a mixed charge will throw readings off. The equipment manufacturer's charging chart and data plate govern.
FAQ
What is R-454B pressure at 40 degrees?
107.0 psig vapor (dew) and 112.0 psig liquid (bubble) at sea level. For superheat use the vapor value.
Is R-454B the same pressure as R-410A?
Close but lower. At 40 °F R-454B vapor is about 107 psig against 118 psig for R-410A; at 105 °F liquid it is about 323 against 342. Use the chart for the refrigerant on the data plate.
Which column do I use for superheat and subcooling?
Vapor (dew) for superheat, liquid (bubble) for subcooling. The superheat and subcooling calculators pick the right one automatically.
Is this tool free?
Yes. No account, no email, no download. It runs in your browser and works on your phone at the unit.