11.18 - Common Refrigerant Pressure-Temperature Tables

Module: Standalone Reference Appendices and Instructor Resources
Purpose: Practical pressure-temperature lookup tables for the refrigerants most useful in this course and in common U.S. HVAC/R service
Final data verification date: August 14, 2026
Full line-by-line re-verification: August 14, 2026; numerical values, pressure-unit state (psig versus in. Hg vacuum), blend-column order, temperature conversion, monotonicity, R-744 critical-limit handling, and the final 104°F EPA pressure-classification comparison were rechecked
Table organization: One table per refrigerant for readability and source traceability
Primary range: -50°F to 150°F in 5°F increments unless the refrigerant’s physical limit requires a shorter range
Primary pressure display: psig above atmospheric pressure; in. Hg vacuum below atmospheric pressure
Temperature display: °F primary with °C alongside
Blend rule: SUPERHEAT → DEW / SATURATED VAPOR; SUBCOOLING → BUBBLE / SATURATED LIQUID

How to Use These Tables

A P-T table links the saturation temperature and saturation pressure of a refrigerant at equilibrium.

Before using a value, identify:

1. CORRECT REFRIGERANT
2. CORRECT TEMPERATURE
3. PRESSURE REFERENCE
4. PURE / NEAR-AZEOTROPIC / ZEOTROPIC BEHAVIOR
5. BUBBLE OR DEW VALUE WHEN THE TABLE PROVIDES BOTH

For zeotropic blends:

SUPERHEAT
→ DEW / SATURATED-VAPOR PRESSURE

SUBCOOLING
→ BUBBLE / SATURATED-LIQUID PRESSURE

A value shown as:

18.3 in. Hg vac

means the saturation pressure is 18.3 inches of mercury below one atmosphere on the conventional vacuum scale used by these reference tables, not -18.3 psig.

A value shown as:

68.6 psig

means 68.6 pounds per square inch gauge.

These tables are intended for P-T lookup, static refrigerant checks, saturation-temperature conversion, and course superheat/subcooling work. Actual operating pressure is not automatically a static saturation condition because vapor may be superheated, liquid may be subcooled, and pressure drops may exist through the system.

Refrigerants Included

The tables below cover 18 widely encountered or instructionally important refrigerants:

• R-22
• R-32
• R-134a
• R-404A
• R-407C
• R-410A
• R-448A
• R-449A
• R-452A
• R-454B
• R-513A
• R-1233zd(E)
• R-123
• R-1234yf
• R-290
• R-600a
• R-717
• R-744

R-22, R-134a, R-404A, R-410A, and R-123 remain important because of the installed equipment base. R-32, R-454B, R-448A, R-449A, R-452A, R-513A, R-1233zd(E), R-1234yf, R-290, R-600a, R-717, and R-744 provide current lower-GWP, natural-refrigerant, transport, commercial-refrigeration, or chiller context.

1. R-22 Pressure-Temperature Table

R-22 is a pure HCFC refrigerant. Use the single saturation-pressure column.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. The chart reports pressure in psig and identifies values below one atmosphere as inches Hg below 1 atm; it states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

2. R-32 Pressure-Temperature Table

R-32 is a pure refrigerant. The high pressures shown here are normal saturation pressures for R-32 and require appropriately rated equipment.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. The chart reports pressure in psig and identifies values below one atmosphere as inches Hg below 1 atm; it states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

3. R-134a Pressure-Temperature Table

R-134a is a pure refrigerant. This table preserves the course-controlled values used in Module 4, including 22.1 psig at 25°F, 35.0 psig at 40°F, and 45.4 psig at 50°F.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. The chart reports pressure in psig and identifies values below one atmosphere as inches Hg below 1 atm; it states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

4. R-404A Pressure-Temperature Table

R-404A is a near-azeotropic blend with small glide. Source [A] publishes one practical R-404A saturation-pressure column. For precision work that specifically requires separate bubble/dew values, use the current equipment/refrigerant manufacturer’s detailed data.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. The chart reports pressure in psig and identifies values below one atmosphere as inches Hg below 1 atm; it states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

5. R-407C Pressure-Temperature Table

Use the liquid/bubble column for subcooling and the vapor/dew column for superheat. R-407C has meaningful temperature glide.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. Liquid and vapor columns are reproduced as bubble/saturated-liquid and dew/saturated-vapor references. The chart states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

6. R-410A Pressure-Temperature Table

R-410A is near-azeotropic with very small glide. Source [A] publishes one practical R-410A saturation-pressure column.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. The chart reports pressure in psig and identifies values below one atmosphere as inches Hg below 1 atm; it states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

7. R-448A Pressure-Temperature Table

Use bubble/liquid for subcooling and dew/vapor for superheat.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. Liquid and vapor columns are reproduced as bubble/saturated-liquid and dew/saturated-vapor references. The chart states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

8. R-449A Pressure-Temperature Table

Use bubble/liquid for subcooling and dew/vapor for superheat.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. Liquid and vapor columns are reproduced as bubble/saturated-liquid and dew/saturated-vapor references. The chart states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

9. R-452A Pressure-Temperature Table

Use bubble/liquid for subcooling and dew/vapor for superheat.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. Liquid and vapor columns are reproduced as bubble/saturated-liquid and dew/saturated-vapor references. The chart states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

10. R-454B Pressure-Temperature Table

Use bubble/liquid for subcooling and dew/vapor for superheat. R-454B is an A2L refrigerant; this P-T table does not replace A2L service/safety requirements.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. Liquid and vapor columns are reproduced as bubble/saturated-liquid and dew/saturated-vapor references. The chart states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

11. R-513A Pressure-Temperature Table

R-513A is an azeotropic/near-zero-glide A1 blend; source [A] nevertheless provides separate liquid and vapor columns, so both are retained.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. Liquid and vapor columns are reproduced as bubble/saturated-liquid and dew/saturated-vapor references. The chart states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

12. R-1233zd(E) Pressure-Temperature Table

R-1233zd(E) is a low-pressure chiller refrigerant. Much of the practical range is below atmospheric pressure, so the table explicitly shows in. Hg vacuum where applicable.

Source [A]: Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025. The chart reports pressure in psig and identifies values below one atmosphere as inches Hg below 1 atm; it states that the data were generated using NIST REFPROP Version 10.0. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

13. R-123 Pressure-Temperature Table

R-123 is a low-pressure chiller refrigerant. Below-atmospheric values are shown as in. Hg vacuum rather than as negative psig.

Source [B]: Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05. Values in this table were calculated from Danfoss’s published R123 controller-fit Antoine constants using the published relationship; Danfoss states that its constants are based on data generated by NIST REFPROP 10.0. Calculated absolute pressure was converted to psig using 14.6959 psia standard atmosphere; below-atmospheric values are displayed as inches Hg vacuum and rounded to 0.1. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

Independent check [D]: NIST Chemistry WebBook lists the normal boiling point of R-123 (HCFC-123) at about 300.2 K (80.7°F). The table’s atmospheric-pressure crossing between 80°F and 85°F is consistent with that independent reference. https://webbook.nist.gov/cgi/cbook.cgi?ID=C306832&Mask=1EFF

14. R-1234yf Pressure-Temperature Table

R-1234yf is a pure A2L HFO. This P-T table does not replace A2L service/safety requirements.

Source [B]: Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05. Values in this table were calculated from Danfoss’s published R1234yf controller-fit Antoine constants using the published relationship; Danfoss states that its constants are based on data generated by NIST REFPROP 10.0. Calculated absolute pressure was converted to psig using 14.6959 psia standard atmosphere; below-atmospheric values are displayed as inches Hg vacuum and rounded to 0.1. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

Independent cross-check [C]: Carrier Transicold T-384 OptimaLINE, R-1234yf refrigerant pressure-temperature chart. Representative values were compared during final QA; the Danfoss/REFPROP-based calculated values track the Carrier service table closely over the overlapping range. https://www.transcentral.carrier.com/CPGTechPubs/ops_service/t384_optimaline/T-384/9_Appendix_OL/9_Appendix_OL.htm

15. R-290 Pressure-Temperature Table

R-290 is propane, an A3 refrigerant. The P-T relationship does not replace hydrocarbon charge-limit, ignition-control, ventilation, tool, listing, code, and manufacturer requirements.

Source [B]: Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05. Values in this table were calculated from Danfoss’s published R290 controller-fit Antoine constants using the published relationship; Danfoss states that its constants are based on data generated by NIST REFPROP 10.0. Calculated absolute pressure was converted to psig using 14.6959 psia standard atmosphere; below-atmospheric values are displayed as inches Hg vacuum and rounded to 0.1. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

Independent check [E]: NIST Chemistry WebBook publishes independent propane vapor-pressure correlations over overlapping temperature ranges. Representative absolute-pressure comparisons show the Danfoss controller correlation follows the same saturation trend and remains within a few percent of the independent NIST correlations across the course range. https://webbook.nist.gov/cgi/cbook.cgi?ID=C74986&Mask=228D

16. R-600a Pressure-Temperature Table

R-600a is isobutane, an A3 refrigerant. The P-T relationship does not replace hydrocarbon service/safety requirements.

Source [B]: Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05. Values in this table were calculated from Danfoss’s published R600a controller-fit Antoine constants using the published relationship; Danfoss states that its constants are based on data generated by NIST REFPROP 10.0. Calculated absolute pressure was converted to psig using 14.6959 psia standard atmosphere; below-atmospheric values are displayed as inches Hg vacuum and rounded to 0.1. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

Independent check [F]: NIST Chemistry WebBook publishes independent isobutane vapor-pressure correlations over overlapping ranges. Representative absolute-pressure comparisons agree closely with the Danfoss/REFPROP-based controller correlation used here. https://webbook.nist.gov/cgi/cbook.cgi?ID=C75285&Mask=1A8F

17. R-717 Pressure-Temperature Table

R-717 is ammonia, B2L. Use ammonia-compatible materials, equipment, PPE, ventilation, and site procedures.

Source [B]: Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05. Values in this table were calculated from Danfoss’s published R717 controller-fit Antoine constants using the published relationship; Danfoss states that its constants are based on data generated by NIST REFPROP 10.0. Calculated absolute pressure was converted to psig using 14.6959 psia standard atmosphere; below-atmospheric values are displayed as inches Hg vacuum and rounded to 0.1. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

Independent check [G]: NIST Chemistry WebBook publishes ammonia Antoine correlations over the temperature range relevant to this table. Representative absolute-pressure comparisons agree closely with the Danfoss/REFPROP-based controller correlation used here. https://webbook.nist.gov/cgi/cbook.cgi?ID=C7664417&Mask=3FB7

18. R-744 (CO₂) Pressure-Temperature Table

R-744 is a very-high-pressure refrigerant. This saturation table intentionally stops at 85°F. CO₂ has a critical temperature of about 87.8°F; above the critical temperature a conventional saturation P-T lookup does not apply.

Source [B]: Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05. Values in this table were calculated from Danfoss’s published R744 controller-fit Antoine constants using the published relationship; Danfoss states that its constants are based on data generated by NIST REFPROP 10.0. Calculated absolute pressure was converted to psig using 14.6959 psia standard atmosphere; below-atmospheric values are displayed as inches Hg vacuum and rounded to 0.1. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

Independent check [H]: NIST Chemistry WebBook reports a CO₂ critical temperature of about 304.18 K (87.85°F). Therefore the saturation table correctly stops at 85°F and does not extend saturation P-T values above the critical point. https://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Mask=4

Critical-point cross-check [D]: NIST Chemistry WebBook / NIST thermophysical-property resources identify the CO₂ critical temperature near 304.1 K (about 87.8°F). The table therefore stops at 85°F, below the critical point; above the critical temperature there is no ordinary liquid-vapor saturation line. https://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Mask=4

Data-Use Notes

Bubble and Dew

Where the source provides separate columns:

SUBCOOLING
→ BUBBLE / SATURATED LIQUID

SUPERHEAT
→ DEW / SATURATED VAPOR

Do not use the midpoint of bubble and dew as a universal replacement for the correct boundary.

Vacuum Values

Source [A] uses inches Hg below one atmosphere for values below atmospheric pressure. Those source-designated vacuum values are retained explicitly in the affected tables.

For Source [B] calculated tables, absolute pressure was converted using:

$$P_{\text{gauge}}=P_{\text{absolute}}-14.6959\text{psi}$$

When the result is below zero gauge, the table displays the equivalent conventional inches-Hg vacuum value rather than a negative psig value.

R-744 Critical Limit

R-744 is fundamentally different above its critical temperature. The saturation table stops at 85°F so it does not imply a liquid-vapor saturation relationship above the approximately 87.8°F critical temperature.

Rounding

Displayed values are rounded to 0.1 in the pressure unit shown. Do not add false decimal precision.

Interpolation

Because the tables use 5°F increments, interpolation is usually unnecessary for course work. When a field procedure requires a value between rows, prefer the current manufacturer app/property software or interpolate only when the required procedure and accuracy permit it.

EPA Section 608 Pressure Classification Comparison at 104°F

EPA Section 608 uses the refrigerant’s liquid-phase saturation pressure at 104°F (40°C) to distinguish low-, medium-, and high-pressure appliances. A very-high-pressure appliance is one that uses a refrigerant with a critical temperature below 104°F or a liquid-phase saturation pressure above 355 psia at 104°F.

The official EPA term is very high pressure. This course does not use the informal term “ultra high pressure” as a regulatory category.

Current §82.152 categories used here are:

LOW
→ liquid-phase saturation pressure below 45 psia at 104°F

MEDIUM
→ liquid-phase saturation pressure between 45 and 170 psia at 104°F

HIGH
→ liquid-phase saturation pressure between 170 and 355 psia at 104°F

VERY HIGH
→ critical temperature below 104°F
OR
→ liquid-phase saturation pressure above 355 psia at 104°F

For zeotropic blends with separate liquid/bubble and vapor/dew columns, the liquid/bubble pressure is used because the regulation specifies liquid-phase saturation pressure.

Source [I] - Regulatory classification: Electronic Code of Federal Regulations, 40 CFR §82.152 - Definitions. The regulation defines low pressure as below 45 psia at 104°F, medium pressure as between 45 and 170 psia, high pressure as between 170 and 355 psia, and very high pressure as a critical temperature below 104°F or liquid-phase saturation pressure above 355 psia at 104°F. The same section explicitly lists R-22, R-407C, and R-410A as high-pressure examples; R-123 as a low-pressure example; and R-134a as a medium-pressure example. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-82/subpart-F/section-82.152*

Source [J] - Arkema-source refrigerants: For R-22, R-32, R-134a, R-404A, R-407C, R-410A, R-448A, R-449A, R-452A, R-454B, R-513A, and R-1233zd(E), the 104°F values were calculated from Arkema’s current Forane Pressure Temperature Chart, PPC/SDC 05-2025. Because that published chart is tabulated in 5°F increments, the 104°F value was obtained by logarithmic interpolation of absolute pressure between the directly published 100°F and 105°F values, then rounded to 0.1 psi. For blends with two columns, the liquid/bubble value was used. https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN*

Source [K] - Danfoss-source refrigerants: For R-123, R-1234yf, R-290, R-600a, and R-717, the 104°F values were calculated directly at 40°C from Danfoss’s current published controller-fit Antoine constants in Refrigerant constants - Antoine equation, AM187286420404en-000702, 2025.05. Danfoss states that the fitted constants are based on NIST REFPROP 10.0 data. https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf*

Source [L] - R-744: NIST Chemistry WebBook reports the CO₂ critical temperature near 304.18 K (87.85°F). Because 104°F is above the critical temperature, R-744 has no ordinary liquid-vapor saturation pressure at 104°F and meets the §82.152 very-high-pressure definition through the critical-temperature criterion. https://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Mask=4*

R-32 boundary check: The interpolated 104°F value is about 359.5 psia, above the 355-psia cutoff. Arkema’s R-32 technical guide independently reports 364.3 psia at 105°F, generated using NIST REFPROP 10.0, supporting the classification immediately above the 104°F regulatory boundary. https://forane.arkema.com/files/live/sites/fluorogases_forane_arkema/files/downloads/literature/forane-r-32-technical-guide-oem-6-pages-single_lr.pdf*

Applicability note: This table applies the thermodynamic pressure-category definitions in §82.152. Pressure category alone does not establish that every refrigerant/end use is subject to every requirement of Section 608 Subpart F. Current exemptions for particular substitutes/end uses are addressed in 11.17 - Common Refrigerant Quick Reference.md and the applicable current regulations.

Final Data Verification Record

The tables in this v3 fully reverified file were audited after the earlier delivered versions.

Arkema tables: 12 refrigerants

For R-22, R-32, R-134a, R-404A, R-407C, R-410A, R-448A, R-449A, R-452A, R-454B, R-513A, and R-1233zd(E):

1. Every published numerical pressure magnitude was compared row-by-row with Arkema’s current PPC/SDC 05-2025 chart.
2. The PDF’s color/font encoding was also checked because Arkema uses green numerals to indicate inches Hg below 1 atmosphere, while black numerals are psig.
3. All pressure magnitudes matched Arkema to the chart’s published 0.1-unit precision.
4. Four unit labels in the first delivered 11.18 were found to be wrong even though their numerical magnitudes were correct. They are corrected in this v2 file:
   • R-407C bubble/liquid at -45°F: 0.6 psig, not 0.6 in. Hg vacuum.
   • R-448A bubble/liquid at -50°F: 0.4 psig, not 0.4 in. Hg vacuum.
   • R-449A bubble/liquid at -50°F: 0.1 psig, not 0.1 in. Hg vacuum.
   • R-452A dew/vapor at -45°F: 0.3 psig, not 0.3 in. Hg vacuum.
5. Liquid/bubble and vapor/dew column order was rechecked for every blend row.

Danfoss-derived tables: 6 refrigerants

For R-123, R-1234yf, R-290, R-600a, R-717, and R-744:

1. Every row was independently recalculated from the current Danfoss AM187286420404en-000702 (2025.05) controller-fit Antoine constants.
2. The Danfoss document states that those constants are based on data generated by NIST REFPROP 10.0.
3. Absolute pressure was converted consistently using 14.6959 psia as the standard atmosphere.
4. Below-atmospheric results were converted to the conventional inches-Hg-vacuum display and rechecked for the correct vacuum/psig transition.
5. Every displayed value in these six tables reproduces the Danfoss correlation to the stated 0.1-unit rounding.
6. R-1234yf was independently compared with Carrier Transicold’s current T-384 service P-T chart at representative temperatures; the two sources track closely over their overlapping range.
7. R-290, R-600a, and R-717 were independently sanity-checked against NIST Chemistry WebBook vapor-pressure correlations. Different correlations are not numerically identical at every point, but no gross discrepancy or incorrect trend was found.
8. R-123’s atmospheric crossing was checked against the NIST normal boiling point.
9. R-744 was checked against NIST’s critical-temperature data and is intentionally stopped at 85°F, below the approximately 87.85°F critical point.

104°F EPA pressure-classification comparison

1. The category thresholds were rechecked against current 40 CFR §82.152.
2. The comparison uses absolute pressure (psia) for classification because the regulation is written in psia.
3. For zeotropic blends, the liquid/bubble pressure is used, matching the regulation’s liquid-phase saturation-pressure wording.
4. Arkema-source 104°F values were independently recalculated from the published 100°F and 105°F source rows using logarithmic interpolation in absolute pressure.
5. Danfoss-source values were independently recalculated directly at 40°C from the published Antoine constants.
6. R-410A remains high pressure at approximately 351.8 psia and is also explicitly identified by §82.152 as a high-pressure example.
7. R-32 is very high pressure at approximately 359.5 psia, just above the 355-psia threshold.
8. R-744 is very high pressure by the critical-temperature criterion; no saturation pressure is reported at 104°F because the temperature is above its critical point.
9. Every one of the 18 refrigerants in this file is represented once in the comparison table.

Whole-file consistency checks

The final v2 file also passed the following automated checks:

• Fahrenheit-to-Celsius conversion for every table row.
• Strictly increasing absolute saturation pressure with increasing temperature for every refrigerant/phase column.
• Bubble/liquid pressure not below dew/vapor pressure at the same temperature for the zeotropic blend tables.
• No R-744 saturation row above its critical temperature.
• All tables retain an explicit source footnote immediately below the table.
• No pressure unit is inferred from numerical sign alone where the primary chart encodes vacuum by typography/color.

Precision note

The Arkema values are direct manufacturer chart values. The six Danfoss tables are values generated from Danfoss’s controller Antoine correlation, which is a fitted engineering correlation based on REFPROP 10.0 data. A fitted controller correlation can differ slightly from another manufacturer’s table or another thermodynamic correlation, particularly near the edges of a range. For precision equipment design, commissioning acceptance limits, or safety-critical engineering calculations, use the exact equipment/refrigerant manufacturer’s current property software or NIST REFPROP rather than treating a rounded field P-T table as a fundamental property standard.

References

[A] Primary Manufacturer P-T Table

Arkema, Forane® Refrigerants Pressure Temperature Chart, PPC/SDC 05-2025, accessed August 14, 2026. The chart states that its data were generated using NIST REFPROP Version 10.0.

https://forane.arkema.com/files/live/sites/shared_arkema/files/downloads/fluorochemicals/Forane%20Ref%20PT%20Regular%20Chart%20EN

[B] Antoine / REFPROP-Based Pure-Refrigerant Source

Danfoss, Refrigerant constants - Antoine equation, Fact Sheet AM187286420404en-000702, 2025.05, accessed August 14, 2026. Danfoss states that the constants are based on NIST REFPROP 10.0.

https://assets.danfoss.com/documents/latest/493262/AM187286420404en-000702.pdf

[C] R-1234yf Cross-Check

Carrier Transicold, T-384 OptimaLINE, R-1234yf refrigerant pressure-temperature service chart, current online manual accessed August 14, 2026.

https://www.transcentral.carrier.com/CPGTechPubs/ops_service/t384_optimaline/T-384/9_Appendix_OL/9_Appendix_OL.htm

[D] Independent NIST Property Context and R-744 Critical Point

National Institute of Standards and Technology, Thermophysical Properties of Fluid Systems / Chemistry WebBook, accessed August 14, 2026.

https://webbook.nist.gov/chemistry/fluid/

https://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Mask=4

Course Cross-References

• 3.3 - Temperature Glide Bubble Point and Dew Point.md
• 4.6 - Gauge Pressure Absolute Pressure and Vacuum.md
• 4.7 - Pressure-Temperature Relationships.md
• 4.8 - Superheat and Subcooling.md
• 11.2 - Acronyms Symbols Units and Conversions.md
• 11.4 - Refrigerant Pressure and Safety Classification Reference.md
• 11.9 - Selected Pressure-Temperature Reference Data.md
• 11.17 - Common Refrigerant Quick Reference.md

Independent Verification Sources

• Carrier Transicold, T-384 OptimaLINE, Table 9-6, R-1234yf Refrigerant Pressure Temperature Chart.
  https://www.transcentral.carrier.com/CPGTechPubs/ops_service/t384_optimaline/T-384/9_Appendix_OL/9_Appendix_OL.htm

• NIST Chemistry WebBook, R-123 / HCFC-123 phase-change data.
  https://webbook.nist.gov/cgi/cbook.cgi?ID=C306832&Mask=1EFF

• NIST Chemistry WebBook, Propane (R-290) vapor-pressure correlations.
  https://webbook.nist.gov/cgi/cbook.cgi?ID=C74986&Mask=228D

• NIST Chemistry WebBook, Isobutane (R-600a) vapor-pressure correlations.
  https://webbook.nist.gov/cgi/cbook.cgi?ID=C75285&Mask=1A8F

• NIST Chemistry WebBook, Ammonia (R-717) vapor-pressure correlations.
  https://webbook.nist.gov/cgi/cbook.cgi?ID=C7664417&Mask=3FB7

• NIST Chemistry WebBook, Carbon dioxide (R-744) phase-change and critical-point data.
  https://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Mask=4