R290 (Propane) PT Chart
Updated October 19, 2026
R-290 · Propane
Pure propane[4], A3 (higher flammability)[1], GWP 3.3 on the US EPA basis[5].
R-290 saturation pressure is 63.9 PSIG at 40°F, 110.2 PSIG at 70°F, and 173.9 PSIG at 100°F. These are the gauge readings on a static, fully-saturated system; a running system's high side sits well above them. The full table below runs from −40°F to 150°F in 1°F steps.
Checked against the NIST Chemistry WebBook (SRD 69) saturation data for propane (R-290)[9] at 18 points from −30°F to 134°F: largest difference 0.005 psi.
R-290 PT chart — printable saturation table
Looking for the R-290 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).
R-290 PT Chart — Pressure-Temperature Saturation Table
Computed with CoolProp 7.2.0 in 1°F steps · hvacptcharts.com
| Temp (°F) | Pressure (PSIG) |
|---|---|
| −40°F | 1.4 |
| −39°F | 1.8 |
| −38°F | 2.2 |
| −37°F | 2.6 |
| −36°F | 3.0 |
| −35°F | 3.4 |
| −34°F | 3.9 |
| −33°F | 4.3 |
| −32°F | 4.8 |
| −31°F | 5.2 |
| −30°F | 5.7 |
| −29°F | 6.1 |
| −28°F | 6.6 |
| −27°F | 7.1 |
| −26°F | 7.6 |
| −25°F | 8.1 |
| −24°F | 8.6 |
| −23°F | 9.1 |
| −22°F | 9.6 |
| −21°F | 10.2 |
| −20°F | 10.7 |
| −19°F | 11.3 |
| −18°F | 11.8 |
| −17°F | 12.4 |
| −16°F | 13.0 |
| −15°F | 13.6 |
| −14°F | 14.2 |
| −13°F | 14.8 |
| −12°F | 15.4 |
| −11°F | 16.1 |
| −10°F | 16.7 |
| −9°F | 17.4 |
| −8°F | 18.0 |
| −7°F | 18.7 |
| −6°F | 19.4 |
| −5°F | 20.1 |
| −4°F | 20.8 |
| −3°F | 21.5 |
| −2°F | 22.2 |
| −1°F | 22.9 |
| 0°F | 23.7 |
| 1°F | 24.5 |
| 2°F | 25.2 |
| 3°F | 26.0 |
| 4°F | 26.8 |
| 5°F | 27.6 |
| 6°F | 28.4 |
| 7°F | 29.2 |
| 8°F | 30.1 |
| 9°F | 30.9 |
| 10°F | 31.8 |
| 11°F | 32.7 |
| 12°F | 33.6 |
| 13°F | 34.5 |
| 14°F | 35.4 |
| 15°F | 36.3 |
| 16°F | 37.2 |
| 17°F | 38.2 |
| 18°F | 39.2 |
| 19°F | 40.1 |
| 20°F | 41.1 |
| 21°F | 42.1 |
| 22°F | 43.2 |
| 23°F | 44.2 |
| 24°F | 45.2 |
| 25°F | 46.3 |
| 26°F | 47.4 |
| 27°F | 48.5 |
| 28°F | 49.6 |
| 29°F | 50.7 |
| 30°F | 51.8 |
| 31°F | 53.0 |
| 32°F H₂O freeze | 54.1 |
| 33°F | 55.3 |
| 34°F | 56.5 |
| 35°F | 57.7 |
| 36°F | 58.9 |
| 37°F | 60.1 |
| 38°F | 61.4 |
| 39°F | 62.7 |
| 40°F | 63.9 |
| 41°F | 65.2 |
| 42°F | 66.5 |
| 43°F | 67.9 |
| 44°F | 69.2 |
| 45°F | 70.6 |
| 46°F | 72.0 |
| 47°F | 73.4 |
| 48°F | 74.8 |
| 49°F | 76.2 |
| 50°F | 77.6 |
| 51°F | 79.1 |
| 52°F | 80.6 |
| 53°F | 82.1 |
| 54°F | 83.6 |
| 55°F | 85.1 |
| 56°F | 86.7 |
| 57°F | 88.2 |
| 58°F | 89.8 |
| 59°F | 91.4 |
| 60°F | 93.0 |
| 61°F | 94.7 |
| 62°F | 96.3 |
| 63°F | 98.0 |
| 64°F | 99.7 |
| 65°F | 101.4 |
| 66°F | 103.1 |
| 67°F | 104.9 |
| 68°F | 106.6 |
| 69°F | 108.4 |
| 70°F | 110.2 |
| 71°F | 112.0 |
| 72°F | 113.9 |
| 73°F | 115.7 |
| 74°F | 117.6 |
| 75°F | 119.5 |
| 76°F | 121.4 |
| 77°F | 123.4 |
| 78°F | 125.4 |
| 79°F | 127.3 |
| 80°F | 129.3 |
| 81°F | 131.4 |
| 82°F | 133.4 |
| 83°F | 135.5 |
| 84°F | 137.6 |
| 85°F | 139.7 |
| 86°F | 141.8 |
| 87°F | 143.9 |
| 88°F | 146.1 |
| 89°F | 148.3 |
| 90°F | 150.5 |
| 91°F | 152.8 |
| 92°F | 155.0 |
| 93°F | 157.3 |
| 94°F | 159.6 |
| 95°F | 161.9 |
| 96°F | 164.3 |
| 97°F | 166.7 |
| 98°F | 169.1 |
| 99°F | 171.5 |
| 100°F | 173.9 |
| 101°F | 176.4 |
| 102°F | 178.9 |
| 103°F | 181.4 |
| 104°F | 183.9 |
| 105°F | 186.5 |
| 106°F | 189.1 |
| 107°F | 191.7 |
| 108°F | 194.3 |
| 109°F | 197.0 |
| 110°F | 199.6 |
| 111°F | 202.4 |
| 112°F | 205.1 |
| 113°F | 207.8 |
| 114°F | 210.6 |
| 115°F | 213.4 |
| 116°F | 216.3 |
| 117°F | 219.1 |
| 118°F | 222.0 |
| 119°F | 224.9 |
| 120°F | 227.8 |
| 121°F | 230.8 |
| 122°F | 233.8 |
| 123°F | 236.8 |
| 124°F | 239.9 |
| 125°F | 242.9 |
| 126°F | 246.0 |
| 127°F | 249.1 |
| 128°F | 252.3 |
| 129°F | 255.5 |
| 130°F | 258.7 |
| 131°F | 261.9 |
| 132°F | 265.2 |
| 133°F | 268.5 |
| 134°F | 271.8 |
| 135°F | 275.1 |
| 136°F | 278.5 |
| 137°F | 281.9 |
| 138°F | 285.4 |
| 139°F | 288.8 |
| 140°F | 292.3 |
| 141°F | 295.8 |
| 142°F | 299.4 |
| 143°F | 303.0 |
| 144°F | 306.6 |
| 145°F | 310.2 |
| 146°F | 313.9 |
| 147°F | 317.6 |
| 148°F | 321.4 |
| 149°F | 325.1 |
| 150°F | 328.9 |
| Temp (°C) | Pressure (kPa) |
|---|---|
| −40°C | 10 |
| −39°C | 15 |
| −38°C | 20 |
| −37°C | 25 |
| −36°C | 30 |
| −35°C | 36 |
| −34°C | 42 |
| −33°C | 48 |
| −32°C | 54 |
| −31°C | 60 |
| −30°C | 67 |
| −29°C | 73 |
| −28°C | 80 |
| −27°C | 87 |
| −26°C | 95 |
| −25°C | 102 |
| −24°C | 110 |
| −23°C | 118 |
| −22°C | 126 |
| −21°C | 135 |
| −20°C | 143 |
| −19°C | 152 |
| −18°C | 161 |
| −17°C | 171 |
| −16°C | 180 |
| −15°C | 190 |
| −14°C | 200 |
| −13°C | 211 |
| −12°C | 222 |
| −11°C | 233 |
| −10°C | 244 |
| −9°C | 256 |
| −8°C | 267 |
| −7°C | 280 |
| −6°C | 292 |
| −5°C | 305 |
| −4°C | 318 |
| −3°C | 331 |
| −2°C | 345 |
| −1°C | 359 |
| 0°C H₂O freeze | 373 |
| 1°C | 388 |
| 2°C | 403 |
| 3°C | 418 |
| 4°C | 434 |
| 5°C | 450 |
| 6°C | 466 |
| 7°C | 483 |
| 8°C | 500 |
| 9°C | 517 |
| 10°C | 535 |
| 11°C | 553 |
| 12°C | 572 |
| 13°C | 591 |
| 14°C | 610 |
| 15°C | 630 |
| 16°C | 650 |
| 17°C | 671 |
| 18°C | 692 |
| 19°C | 713 |
| 20°C | 735 |
| 21°C | 757 |
| 22°C | 780 |
| 23°C | 803 |
| 24°C | 827 |
| 25°C | 851 |
| 26°C | 875 |
| 27°C | 900 |
| 28°C | 926 |
| 29°C | 951 |
| 30°C | 978 |
| 31°C | 1,004 |
| 32°C | 1,032 |
| 33°C | 1,060 |
| 34°C | 1,088 |
| 35°C | 1,117 |
| 36°C | 1,146 |
| 37°C | 1,176 |
| 38°C | 1,206 |
| 39°C | 1,237 |
| 40°C | 1,268 |
| 41°C | 1,300 |
| 42°C | 1,332 |
| 43°C | 1,365 |
| 44°C | 1,399 |
| 45°C | 1,433 |
| 46°C | 1,468 |
| 47°C | 1,503 |
| 48°C | 1,539 |
| 49°C | 1,575 |
| 50°C | 1,612 |
| 51°C | 1,650 |
| 52°C | 1,688 |
| 53°C | 1,726 |
| 54°C | 1,766 |
| 55°C | 1,806 |
| 56°C | 1,846 |
| 57°C | 1,888 |
| 58°C | 1,930 |
| 59°C | 1,972 |
| 60°C | 2,015 |
| 61°C | 2,059 |
| 62°C | 2,104 |
| 63°C | 2,149 |
| 64°C | 2,195 |
| 65°C | 2,242 |
| 66°C | 2,289 |
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-290 PT chart data: CoolProp 7.2.0 (published Helmholtz equations of state / mixture models — see the source citations above).
Lower toxicity, higher flammability. ASHRAE 34 class 3: lower flammability limit ≤ 0.10 kg/m³ or heat of combustion ≥ 19,000 kJ/kg. Includes hydrocarbons R-290 (propane), R-600a (isobutane), R-1150 (ethylene), R-1270 (propylene).
- Flammability
- Higher (LFL ≤ 0.10 kg/m³ or HoC ≥ 19,000 kJ/kg)
- Toxicity
- Lower
Classification per ANSI/ASHRAE Standard 34-2022[1], safety group definitions and refrigerant safety classifications. See full reference.
Saturation pressure-temperature curve
Saturation values from CoolProp 7.2.0[3]. Operating pressure on a running system differs — see the operating-pressure references for in-use values.
At a glance
Chemistry
Lubricant compatibility
Highly flammable (A3).
Common applications
- Household refrigerators and freezers
Properties
- Boiling point (1 atm)−43.8°F (−42.1°C)
- Critical point206.1°F (96.7°C) at 602 PSIG
- Molar mass44.10 g/mol
- ODP0
- GWP (100-yr)3.3 US EPA value, 40 CFR 84.64(b) IPCC: AR4 not assessed · AR5 not assessed · AR6 0.02 40 CFR 84.64(b) uses 3.3, the AR4 indirect GWP (Table 2.15); AR6 lists only the direct GWP (0.02).
- Atmospheric lifetime0.04 years
- New-equipment status (US)Not an AIM Act regulated substance; 40 CFR 84.54 GWP limits don't apply.
What is R-290?
Regulatory & phase-down status
R-290 is not on the AIM Act's list of regulated substances (42 U.S.C. 7675(c)(1)), so the US HFC phase-down does not apply to it[2].
Operating cycle
Phase-down timeline
R-290 is not an AIM Act regulated substance (not one of the 18 HFCs in 42 U.S.C. 7675(c), and not a blend containing one). The 40 CFR 84.54 GWP limits don't apply.
Global warming potential, in context
Household refrigeration
Retrofit and replacement paths
Reading the R-290 pressure-temperature chart
R-290's PT chart is a single saturation curve. R-290 is pure propane with no temperature glide and no bubble/dew distinction[1]. Read across from temperature to saturation pressure or vice versa, identically to R-22, R-32, or R-134a.
R-290 has no glide because it is a single-component substance. The simplicity helps service: no bubble/dew curve distinction, no fractionation concern during partial charging, no composition shift in leaking systems.
R-290 vs R-22, R-134a, R-404A: saturation pressure
| Temp | R-290 | R-22 | R-134a | R-404A |
|---|---|---|---|---|
| 0°F | 23.7 | 24.0(+1%) | 6.5(−73%) | 33.7(+42%) |
| 40°F | 63.9 | 68.6(+7%) | 35.0(−45%) | 86.9(+36%) |
| 70°F | 110.2 | 121.4(+10%) | 71.1(−35%) | 149.3(+35%) |
| 100°F | 173.9 | 195.9(+13%) | 124.2(−29%) | 236.8(+36%) |
Frequently asked
›What is the normal operating pressure of R-290?
Operating pressure depends on evaporator load and ambient. The saturation pressures are in the PT table and the comparison table on this page.
›What's R-290's GWP?
3.3 on the US EPA basis (40 CFR 84.64(b)), essentially zero compared to HFC alternatives like R-410A or R-404A[5].
Sources & citations
- [1]ANSI/ASHRAE Standard 34-2022, Designation and Safety Classification of Refrigerants (free read-only version). ASHRAE. 2022. https://www.ashrae.org/technical-resources/standards-and-guidelines/read-only-versions-of-ashrae-standards (accessed October 2, 2026)
- [2]42 U.S.C. 7675 — American Innovation and Manufacturing Act. US Code (via Cornell LII). current. https://www.law.cornell.edu/uscode/text/42/7675 (accessed October 2, 2026)
- [3]CoolProp 7.2.0. CoolProp (I. H. Bell, J. Wronski, S. Quoilin, V. Lemort). https://coolprop.org/ (accessed October 2, 2026). Bell, I. H.; Wronski, J.; Quoilin, S.; Lemort, V. Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp. Ind. Eng. Chem. Res. 53, 2498–2508 (2014). https://doi.org/10.1021/ie4033999
- [4]ASHRAE Refrigerant Designations. ASHRAE. web page, updated May 25, 2021. https://www.ashrae.org/technical-resources/standards-and-guidelines/ashrae-refrigerant-designations (accessed October 2, 2026)
- [5]40 CFR 84.64 — Global warming potentials. eCFR (Office of the Federal Register). current as of 9/28/2026. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-84/subpart-B/section-84.64 (accessed October 2, 2026)
- [6]Substitutes in Household Refrigerators and Freezers. US EPA (SNAP). last updated March 16, 2026. https://www.epa.gov/snap/substitutes-household-refrigerators-and-freezers (accessed October 2, 2026)
- [7]NIOSH Pocket Guide to Chemical Hazards — Propane. CDC/NIOSH. web page. https://www.cdc.gov/niosh/npg/npgd0524.html (accessed October 2, 2026)
- [8]2017 Guideline for Assignment of Refrigerant Container Colors (AHRI Guideline N-2017). AHRI. 2017. https://www.ahrinet.org/system/files/2023-06/AHRI_Guideline_N_2017.pdf (accessed October 2, 2026)
- [9]NIST Chemistry WebBook (SRD 69) saturation data for propane (R-290). NIST. https://webbook.nist.gov/cgi/fluid.cgi?TLow=-40&THigh=150&TInc=10&Digits=6&ID=C74986&Action=Load&Type=SatT&TUnit=F&PUnit=psia&DUnit=lbm%2Fft3&HUnit=Btu%2Flbm&WUnit=ft%2Fs&VisUnit=uPa*s&STUnit=lb%2Fin&RefState=DEF (accessed October 2, 2026). NIST reference equation of state for this fluid
- [10]Technology Transitions GWP Reference Table. US EPA. updated April 2, 2026. https://www.epa.gov/hfcs/technology-transitions-gwp-reference-table (accessed October 2, 2026)
- [11]Substitutes in Residential and Light Commercial Air Conditioning and Heat Pumps. US EPA (SNAP). last updated March 19, 2026. https://www.epa.gov/snap/substitutes-residential-and-light-commercial-air-conditioning-and-heat-pumps (accessed October 5, 2026)