R-454B / Puron Advance (A2L, near-azeotrope)
R-454B PT Chart
The full R-454B pressure-temperature reference table, from -20 to 130°F, with both the bubble and dew columns its about 2°F glide requires. Use the dew point for superheat and the bubble point for subcooling. Checked cell by cell against 4 other published tables, 2 of them separate publishers: Arkema, Chemours, Honeywell and Weitron. Three of them, Weitron, Arkema and Chemours, have full columns on file here, so this chart prints where those tables and ours disagree at every pressure instead of quietly picking one. The widest gap on the bubble column, which is the one compared here, is 0.69 degrees F, against Weitron, Arkema and Chemours, at 58.5 psig.
R-454B Pressure-Temperature Table
| R-454B | |||
|---|---|---|---|
| Pressure (psig) | Bubble °F (subcooling) | Dew °F (superheat) | Publisher spread (°F) |
| 24.3 | -20°F | -18.3°F | 0.67 |
| 33.9 | -10°F | -7.9°F | 0.67 |
| 45.3 | 0°F | 1.9°F | 0.64 |
| 58.5 | 10°F | 12.2°F | 0.69 |
| 73.9 | 20°F | 22°F | 0.67 |
| 91.7 | 30°F | 32.3°F | 0.63 |
| 112 | 40°F | 42.1°F | 0.60 |
| 135 | 50°F | 52.4°F | 0.65 |
| 161.1 | 60°F | 62.1°F | 0.65 |
| 190.5 | 70°F | 72.4°F | 0.65 |
| 223.4 | 80°F | 82.2°F | 0.64 |
| 260 | 90°F | 92.4°F | 0.65 |
| 300.8 | 100°F | 102.1°F | 0.65 |
| 345.9 | 110°F | 112.3°F | 0.65 |
| 395.7 | 120°F | 122.1°F | 0.66 |
| 450.5 | 130°F | 132.2°F | 0.66 |
About the spread column. It is the widest gap in saturation temperature between the published tables we hold, at that pressure, on the bubble column. Across this chart the widest is 0.69°F, at 58.5 psig. Our table and 3 other published tables are compared here: 1 is a separate publisher, and 2 resolve to the same equation of state as our base, so those are consistency checks rather than independent confirmation. A narrow spread means the charts agree, which is not the same as the charts being right: they are all computed from equations of state fitted to lab data, and no field measurement settles it.
- Checked against Arkema Forane 454B, within 0.1 psig [same model]
- Checked against Chemours Opteon XL41, within 0.05 psig [same model]
- Checked against Honeywell Solstice 454B, within 2 psig [separate publisher]
- Checked against Weitron, reprinted as Daikin/Goodman PM-A2LPTC-USA_04-24, bubble line about 0.64 F away [separate publisher]
Arkema and Chemours make this blend, and both state their tables were generated from NIST REFPROP, the same equation-of-state lineage our own base resolves to. Their agreement is close and it is not independent confirmation. Weitron is the one table that disagrees: its bubble line sits about 0.64 F from ours across the whole range, a constant offset rather than noise, and no further chart can settle which is right. The calculator says so on any reading close enough to a band edge for that difference to change the call.
A separate publisher can catch a transcription, edition or rounding error. A cross-check marked same model resolves to the same equation of state as the base table, so it is a consistency check rather than independent confirmation. One marked same printing prints numbers identical to another table listed here, so the two are one witness and we do not count them twice. Sources last re-verified 2026-08-25.
Read the low-side (suction) pressure and its dew temperature for superheat, and the high-side (liquid) pressure and its bubble temperature for subcooling. The chart is in psig (gauge) and °F. To convert: kPa gauge = psig × 6.895; °C = (°F − 32) / 1.8.
R-454B PT Chart FAQs
What is the R-454B pressure at a 40F bubble point?
On the R-454B PT chart, a 40F bubble point corresponds to about 112 psig, where the dew point is 42.1F. At 260 psig the bubble point is 90F and the dew point is 92.4F. R-454B (Puron Advance) is a near-azeotropic A2L blend with only about 2F of glide, so its pressures sit close to R-410A but a hair lower.
Why does the R-454B PT chart have two temperature columns?
R-454B is a zeotropic blend, so at any given pressure it boils and condenses across a small range of temperatures rather than at one point. The lower temperature is the bubble point and the higher one is the dew point; the gap is the glide, only about 2 degrees F for R-454B, which is why it is called a near-azeotrope. Because the glide is small, the two columns are close, but the table still lists both so you read the correct one.
Do I use bubble or dew point for R-454B superheat and subcooling?
Use the dew point for superheat and the bubble point for subcooling. Superheat is measured on the suction line where the refrigerant is fully vapor, which is the dew side. Subcooling is measured on the liquid line where it is fully liquid, which is the bubble side. R-454B's glide is only about 2F, so the penalty for reading the wrong column is small, but reading it right keeps the charge diagnosis clean.
Is the R-454B PT chart the same as R-410A?
Very close but not identical. R-454B runs a few psig below R-410A at the same temperature, which is why R-454B is a low-glide near-match on the pressure side and the R-410A line set is usually pressure-adequate. It is still not a drop-in: R-454B is A2L (mildly flammable), so it requires A2L-listed equipment, leak detection, and A2L service practices.
Related R-454B Tools
R-454B Superheat & Subcooling Calculator
Enter your readings; the calculator splits bubble and dew for you and returns the verdict.
R-454B vs R-410A
Pressures, GWP, glide, and why the line set reuses without an oil flush.
A2L Charge Limit Calculator
Maximum R-454B charge for a room, or minimum room area for a charge, per UL 60335-2-40.
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