HVAC PT Charts
RefrigerantASHRAE R-457A

R457A PT Chart

Updated October 19, 2026

R-457A

A2L Lower toxicity, lower flammabilityHFC/HFO blend AIM Act HFC
R-457A AHRI Guideline N service cylinderIllustration of a refrigerant cylinder painted light green gray (RAL 7044), the color AHRI Guideline N-2017 calls for on all new refrigerant containers from 2020. Label: R457A, safety class A2L, GWP 137. Red band on the shoulder: AHRI Guideline N-2017 calls for one on containers of flammable refrigerants.R457AA2LGWP 137
Illustration of a refrigerant cylinder painted light green gray (RAL 7044), the color AHRI Guideline N-2017 calls for on all new refrigerant containers from 2020[1], section 4.8. Label: R-457A, safety class A2L, GWP 137. Red band on the shoulder: AHRI Guideline N-2017 calls for one on containers of flammable refrigerants[1], section 4.7.
R-32/R-152a/R-1234yf (18/12/70)

Ternary HFC/HFO blend (18% R-32 / 70% R-1234yf / 12% R-152a). A2L lower flammability; very low GWP (137). Designed as a low-GWP replacement for R-404A and R-22 in commercial refrigeration. Significant temperature glide (~12°F).

R-457A saturation pressure splits across its glide: dew 55.0 PSIG at 40°F, bubble 200.2 PSIG at 100°F, and 101.7–125.6 PSIG dew-to-bubble at 70°F. Use the dew column for superheat and the bubble column for subcooling. The full table below runs from −40°F to 150°F in 1°F steps.

Not yet checked against an independent source.

Saturation @ 70°F
125.6 / 101.7 PSIG
GWP (100-yr)
137 US EPA value, 40 CFR 84.64(b)
Temperature glide
12.6°F
Boiling point
bubble −44.7°F / dew −32.0°F
Sourced facts
Temperature glide
12.6°F at a 40°F dew point[3]
R-457A PT calculator Superheat

R-457A PT chart — printable saturation table

Looking for the R-457A 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-457A PT Chart — Pressure-Temperature Saturation Table

Computed with CoolProp 7.2.0 in 1°F steps · hvacptcharts.com

R-457A · 1° increments · °F / PSIG
Tinted rows: 32°F H₂O freeze
R-457A pressure-temperature saturation table in Fahrenheit and PSIG
Temp (°F)Bubble (PSIG)Dew (PSIG)
−40°F 1.95.7 in. Hg vac.
−39°F 2.35.1 in. Hg vac.
−38°F 2.74.4 in. Hg vac.
−37°F 3.23.7 in. Hg vac.
−36°F 3.63.0 in. Hg vac.
−35°F 4.12.3 in. Hg vac.
−34°F 4.51.5 in. Hg vac.
−33°F 5.00.8 in. Hg vac.
−32°F 5.50.0 in. Hg vac.
−31°F 6.00.4
−30°F 6.50.8
−29°F 7.01.2
−28°F 7.51.6
−27°F 8.12.0
−26°F 8.62.4
−25°F 9.12.8
−24°F 9.73.3
−23°F 10.33.7
−22°F 10.84.2
−21°F 11.44.6
−20°F 12.05.1
−19°F 12.65.6
−18°F 13.36.1
−17°F 13.96.6
−16°F 14.57.1
−15°F 15.27.6
−14°F 15.98.2
−13°F 16.58.7
−12°F 17.29.2
−11°F 17.99.8
−10°F 18.610.4
−9°F 19.411.0
−8°F 20.111.6
−7°F 20.812.2
−6°F 21.612.8
−5°F 22.413.4
−4°F 23.214.0
−3°F 24.014.7
−2°F 24.815.3
−1°F 25.616.0
0°F 26.416.7
1°F 27.317.4
2°F 28.118.1
3°F 29.018.8
4°F 29.919.5
5°F 30.820.3
6°F 31.721.0
7°F 32.721.8
8°F 33.622.6
9°F 34.623.3
10°F 35.524.1
11°F 36.525.0
12°F 37.525.8
13°F 38.526.6
14°F 39.627.5
15°F 40.628.4
16°F 41.729.2
17°F 42.830.1
18°F 43.931.1
19°F 45.032.0
20°F 46.132.9
21°F 47.233.9
22°F 48.434.8
23°F 49.635.8
24°F 50.736.8
25°F 52.037.8
26°F 53.238.9
27°F 54.439.9
28°F 55.741.0
29°F 56.942.0
30°F 58.243.1
31°F 59.544.2
32°F H₂O freeze60.945.4
33°F 62.246.5
34°F 63.647.7
35°F 64.948.8
36°F 66.350.0
37°F 67.851.2
38°F 69.252.5
39°F 70.653.7
40°F 72.155.0
41°F 73.656.2
42°F 75.157.5
43°F 76.658.8
44°F 78.260.2
45°F 79.761.5
46°F 81.362.9
47°F 82.964.3
48°F 84.665.7
49°F 86.267.1
50°F 87.968.5
51°F 89.570.0
52°F 91.371.5
53°F 93.073.0
54°F 94.774.5
55°F 96.576.0
56°F 98.377.6
57°F 100.179.2
58°F 101.980.8
59°F 103.882.4
60°F 105.684.0
61°F 107.585.7
62°F 109.587.4
63°F 111.489.1
64°F 113.490.8
65°F 115.492.6
66°F 117.494.3
67°F 119.496.1
68°F 121.498.0
69°F 123.599.8
70°F 125.6101.7
71°F 127.7103.5
72°F 129.9105.4
73°F 132.1107.4
74°F 134.2109.3
75°F 136.5111.3
76°F 138.7113.3
77°F 141.0115.3
78°F 143.3117.4
79°F 145.6119.5
80°F 147.9121.6
81°F 150.3123.7
82°F 152.7125.8
83°F 155.1128.0
84°F 157.5130.2
85°F 160.0132.4
86°F 162.5134.7
87°F 165.0137.0
88°F 167.5139.3
89°F 170.1141.6
90°F 172.7143.9
91°F 175.3146.3
92°F 178.0148.7
93°F 180.7151.2
94°F 183.4153.6
95°F 186.1156.1
96°F 188.9158.7
97°F 191.6161.2
98°F 194.5163.8
99°F 197.3166.4
100°F 200.2169.0
101°F 203.1171.7
102°F 206.0174.4
103°F 208.9177.1
104°F 211.9179.9
105°F 214.9182.6
106°F 218.0185.5
107°F 221.1188.3
108°F 224.2191.2
109°F 227.3194.1
110°F 230.4197.0
111°F 233.6200.0
112°F 236.9203.0
113°F 240.1206.0
114°F 243.4209.1
115°F 246.7212.2
116°F 250.0215.3
117°F 253.4218.5
118°F 256.8221.7
119°F 260.2224.9
120°F 263.7228.2
121°F 267.2231.5
122°F 270.7234.9
123°F 274.3238.2
124°F 277.9241.6
125°F 281.5245.1
126°F 285.2248.6
127°F 288.9252.1
128°F 292.6255.6
129°F 296.3259.2
130°F 300.1262.8
131°F 304.0266.5
132°F 307.8270.2
133°F 311.7273.9
134°F 315.6277.7
135°F 319.6281.5
136°F 323.6285.4
137°F 327.6289.3
138°F 331.7293.2
139°F 335.8297.2
140°F 339.9301.2
141°F 344.1305.3
142°F 348.3309.4
143°F 352.5313.5
144°F 356.8317.7
145°F 361.1322.0
146°F 365.4326.2
147°F 369.8330.6
148°F 374.2334.9
149°F 378.7339.3
150°F 383.2343.8
CoolProp 7.2.0 · PSIG/kPa = gauge · PSIA = PSIG + 14.6959 · kPa(abs) = kPa(gauge) + 101.325

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-457A PT chart data: CoolProp 7.2.0 (published Helmholtz equations of state / mixture models — see the source citations above).

A2L
Lower toxicity, lower flammability

Lower toxicity. Flame propagates in air at 60°C, but with a low burning velocity (≤ 10 cm/s) and a heat of combustion < 19,000 kJ/kg. ASHRAE safety group A2L: lower toxicity and lower flammability. R-32, R-454B, R-1234yf, R-1234ze(E), R-452B, R-454C, R-455A, R-516A are A2L.

Flammability
Low (burning velocity ≤ 10 cm/s)
Toxicity
Lower (OEL ≥ 400 ppm)

Classification per ANSI/ASHRAE Standard 34-2022. See full reference.

Saturation pressure-temperature curve

Pressure
Temperature
°F
70°F: 125.6 PSIG (bubble)101.7 PSIG (dew)
Quick lookup — R-457A
125.6 / 101.7PSIG(866 / 701 kPa)
Bubble Dew· zeotropic blend
Range: −40 to 150°F Open full PT calculator →
Common service temperatures
32°F
61 / 45PSIG
Freezing
45°F
80 / 62PSIG
Heat-pump heat
70°F
126 / 102PSIG
Standard
75°F
136 / 111PSIG
Test ref
80°F
148 / 122PSIG
Warm
95°F
186 / 156PSIG
Summer peak

Saturation values from CoolProp 7.2.0 mixture model: R-32/R-152a/R-1234yf, 18/12/70% by mass[3]. Operating pressure on a running system differs — see the operating-pressure references for in-use values.

At a glance

Chemistry

R-32/R-152a/R-1234yf (18/12/70)
Ternary HFC/HFO blend

Lubricant compatibility

POEMO

POE required. A2L. Very low GWP. Less commonly deployed than R-454C or R-455A but offers similar performance envelope.

Blend composition

  • R-32 18.0%
  • R-152a 12.0%
  • R-1234yf 70.0%

Common applications

  • Commercial refrigeration (medium temp)
  • R-404A retrofit option

Properties

  • Boiling point (1 atm)
    bubble −44.7°F (−42.6°C), dew −32.0°F (−35.5°C)
  • Critical point
    No single point — blend critical locus
  • Molar mass
    87.61 g/mol
  • Temperature glide
    12.6°F
  • ODP
    0
  • GWP (100-yr)
    137 US EPA value, 40 CFR 84.64(b) IPCC: AR4 not assessed · AR5 139 · AR6 159
  • New-equipment status (US)
    AIM Act HFC, 84.64 GWP 137 — below every 40 CFR 84.54 limit; no new-equipment restriction.

What is R-457A?

R-457A is a ternary blend combining R-32 (HFC), R-1234yf (HFO), and R-152a (HFC). Mass composition: 18% R-32, 70% R-1234yf, 12% R-152a. All three components are mildly to moderately flammable; the blend is classified A2L (lower flammability, low burning velocity). The very low GWP of 137 places it below every 40 CFR 84.54 limit (the lowest is 150) and below the 150 limit in 517/2014 Annex III rows 11 and 13.

R-457A targets the same application space as R-454C (R-32/R-1234yf 21.5/78.5, GWP 146) and R-455A (R-744/R-32/R-1234yf 3/21.5/75.5, GWP 146): low-GWP commercial refrigeration replacing R-404A. The presence of R-152a in R-457A distinguishes it — the 12% R-152a contributes capacity and reduces the GWP slightly, but also widens the temperature glide.

Where R-457A is used

  • Medium-temperature commercial refrigeration (replacing R-404A in new equipment)
  • R-404A retrofit option for existing equipment with POE oil
  • Some R-22 retrofit applications where low-GWP and A2L acceptability align

Regulatory & phase-down status

R-457A's GWP is 137. It is below every 40 CFR 84.54 limit (the lowest is 150), meaning it remains permitted for new equipment installations. The A2L classification is the limiting factor for application breadth — A2L acceptable-use designations require A2L-listed equipment, ventilation interlocks where appropriate, and explicit A2L charge limits.

For very-low-GWP applications R-744 (CO₂ transcritical) competes where the equipment investment is justified.

Service notes

POE oil is required; mineral oil is incompatible. The A2L classification requires service practices appropriate for lower flammability refrigerants: refrigerant detection where the standard requires it; recovery cylinders must be rated for the refrigerant.

R-457A has substantial temperature glide (~12.5°F per CoolProp). Superheat measurement uses the dew curve; subcooling uses the bubble curve. TXV systems generally accommodate moderate glide; very-large-glide blends (>15°F) may require adjustment. EPA Section 608 Universal or appropriate class certification covers R-457A handling.

Temperature glide

Temperature glide across evaporator at constant pressureR-457A at 72 PSIG suction→ refrigerant flow →Entry: 40.0°F Mid: 46.2°F Exit: 52.4°F Glide = 12.4°F Position along evaporator coil40°F 52°F

R-457A is a zeotropic blend: at constant pressure it boils across a temperature range rather than at a single point. Use the dew curve for superheat, bubble curve for subcooling.

Operating cycle

CompressorRaises pressureCondenserRejects heat to outdoorsExpansion deviceDrops pressureEvaporatorAbsorbs heat from indoorsDischarge: 230 PSIG, 180°F Liquid: 230 PSIG, 100°F Evap inlet: 55 PSIG, 40°F (two-phase)Suction: 55 PSIG, 50°F Example cycle for R-457A (40°F evap, 110°F condenser, 10°F superheat, 10°F subcooling)

Phase-down timeline

R-457A contains HFC-32 and HFC-152a, regulated substances under the AIM Act. Its GWP under 40 CFR 84.64 is 137 — below every 40 CFR 84.54 GWP limit, so no 84.54 new-equipment limit restricts it.

HFC production & consumption allowances step down to 30% of baseline in 2029–2033, 20% of baseline in 2034–2035, and 15% of baseline in 2036 and later (42 U.S.C. 7675(e)(2)(C)).

Full 40 CFR 84.54 new-equipment rules for R-457A →

US new-equipment rules (40 CFR 84.54)

R-457A contains HFC-32 and HFC-152a, regulated substances under the AIM Act. Under 40 CFR 84.64(b) its GWP is 137: each component's GWP times its mass fraction; components without a GWP under 84.64 are left out (84.64(c)). That value is compared against each 40 CFR 84.54 subsector limit below.

Servicing. 40 CFR 84.54 restricts new manufacture/import, later sale/distribution, and installation. "Installation" is defined in 84.54(e); repairing or servicing existing R-457A equipment is not an installation unless it meets 84.54(e), so existing systems can keep being serviced. From January 1, 2029, servicing or repairing R-457A equipment in supermarket systems, refrigerated transport or automatic commercial ice makers must be done with reclaimed refrigerant[2].

Source: 40 CFR 84.54, current through 91 FR 31329 (May 26, 2026). Installation defined at 40 CFR 84.54(e).

Global warming potential, in context

Commercial refrigeration — medium temperature

R-7441R-516A140R-454C146R-455A146R-450A601R-513A630R-448A1.4kR-449A1.4kR-407C1.8kR-221.8kR-407F1.8kR-407A2.1kR-404A3.9k

Retrofit and replacement paths

R-457A replaces

R-457A vs R-404A, R-22: saturation pressure

Saturation pressure (PSIG, gauge) for R-457A vs R-404A, R-22 — zeotropic blends shown as dew / bubble. Each column shows the percent difference from R-457A. Source: CoolProp 7.2.0 dataset.
TempR-457AR-404AR-22
0°F16.7 / 26.433.7(+27%)24.0(−9%)
40°F55.0 / 72.186.9(+21%)68.6(−5%)
70°F101.7 / 125.6149.3(+19%)121.4(−3%)
100°F169.0 / 200.2236.8(+18%)195.9(−2%)

Frequently asked

›How does R-457A compare to R-454C for R-404A replacement?

R-457A's 12.5°F glide is close to R-454C's (~14°F), and both are wide enough to complicate TXV behavior on some equipment. R-457A remains a valid technical choice for R-404A replacement.

›What's the temperature glide of R-457A?

Approximately 12.5°F (CoolProp at 0°C). This is substantial — at low evaporator setpoints (e.g., −20°F for low-temperature commercial), the bubble-to-dew temperature difference at the evaporator inlet is ~12°F, meaning the suction-line saturation temperature differs noticeably from the evaporator-inlet saturation. Use the dew curve for superheat measurement; the dew temperature at the suction pressure is the proper boundary.

›What is the GWP of R-457A?

137, mass-weighted from R-32 (675) at 18%, R-1234yf (1) at 70%, R-152a (124) at 12%. This is below the 150 limit in 517/2014 Annex III rows 11 and 13, and below every 40 CFR 84.54 limit (the lowest is 150). It is lower than R-454C (146) and R-455A (146).

›Is R-457A approved for commercial refrigeration?

Yes for new equipment installations meeting A2L charge limits and equipment design requirements. R-22 and R-404A retrofit applications require the equipment to be evaluated for A2L compatibility — older A1-rated equipment is generally NOT permitted to be retrofitted to A2L without OEM approval.

›Why does R-457A include R-152a instead of going pure HFC-32/HFO-1234yf like R-454C?

R-152a addition serves two purposes: (1) capacity tuning — R-152a's vapor pressure profile is slightly different from R-1234yf's, allowing fine-tuning of the blend's capacity at specific evaporator setpoints; (2) GWP fine-tuning — R-152a (GWP 124) is lower than R-32 (GWP 675), so adding R-152a in place of some R-32 modestly reduces overall blend GWP. The tradeoff is added complexity in the blend and the slightly different flammability characteristics of R-152a (A2) vs R-32 (A2L) — in the blend the overall classification stays A2L.

Download this dataset

Full PT chart for R-457A · CC BY 4.0 · attribute the source

CSV JSON

Sources & citations

  1. [1]
    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)
  2. [2]
    40 CFR 84.112 — Reclamation. eCFR (Office of the Federal Register). up to date as of 9/25/2026. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-84/subpart-C/section-84.112 (accessed October 2, 2026). 89 FR 82859, Oct. 11, 2024
  3. [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

Data sources & provenance

PT chart
CoolProp 7.2.0 mixture model: R-32/R-152a/R-1234yf, 18/12/70% by mass
Properties
CoolProp 7.2.0 + ASHRAE Standard 34-2022
GWP (100-yr)
US EPA value, 40 CFR 84.64(b) · IPCC AR4/AR5/AR6 on the GWP rankings
Table computed
October 2026

Reference material. Always verify pressure values against the equipment data plate and manufacturer service literature before charging or troubleshooting a specific system. Saturation pressure differs from operating pressure — see superheat & subcooling fundamentals. See how this PT table is calculated in our methodology.