R454B (trade names: Opteon™ XL41, Puron Advance®, Solstice® 454B) is an HFC/HFO zeotropic blend composed of 68.9% R-32 and 31.1% R-1234yf. With a Global Warming Potential (GWP) of 466 — 78% lower than R410A’s 2,088 — it became the mandatory replacement for R410A in new U.S. residential and light commercial AC systems from January 1, 2025 under the EPA AIM Act.

This page covers everything engineers, HVAC technicians and procurement teams need: the full pressure-temperature (PT) chart, physical properties, a side-by-side comparison with R410A, and guidance on which Geson chiller models are factory-configured for R454B.

R454B Pressure Temperature Chart (PT Chart)

The table below lists vapor pressure in PSIG at saturation temperatures from −40 °F to 150 °F (−40 °C to 65.6 °C). Because R454B is a zeotropic blend, bubble point and dew point pressures differ slightly; both are shown.

Use case: On a 90 °F ambient day, target suction-side vapor pressure ≈ 260 psig. Readings below 200 psig at 80 °F suggest undercharge or a leak; above 350 psig suggest overcharge or airflow restriction.

Temp (°F) Temp (°C) Bubble Point (PSIG) Dew Point (PSIG)
−40 −40.0 9.5 8.8
−35 −37.2 12.7 11.8
−30 −34.4 16.3 15.2
−25 −31.7 20.4 19.1
−20 −28.9 25.0 23.4
−15 −26.1 30.1 28.2
−10 −23.3 35.7 33.6
−5 −20.6 41.9 39.5
0 −17.8 48.8 46.1
5 −15.0 56.4 53.4
10 −12.2 64.7 61.4
15 −9.4 73.8 70.2
20 −6.7 83.8 79.8
25 −3.9 94.7 90.4
30 −1.1 106.6 101.9
35 1.7 119.5 114.4
40 4.4 133.6 128.0
45 7.2 148.8 142.8
50 10.0 165.2 158.7
55 12.8 182.9 175.9
60 15.6 202.0 194.5
65 18.3 222.5 214.4
70 21.1 244.5 235.8
75 23.9 268.0 258.7
80 26.7 293.1 283.1
85 29.4 319.9 309.1
90 32.2 348.4 336.9
95 35.0 378.7 366.5
100 37.8 410.8 397.9
105 40.6 444.8 431.2
110 43.3 480.8 466.4
115 46.1 518.8 503.5
120 48.9 558.9 543.0
125 51.7 601.2 584.4
130 54.4 645.6 628.0
140 60.0 740.5 721.0
150 65.6 844.9 823.0

Field tip: R454B has a temperature glide of approximately 1.4–1.8 °F. When measuring superheat and subcooling, use the dew point for suction-side calculations and the bubble point for liquid-line calculations. Always use A2L-rated manifold gauges — standard R410A gauges are not certified for A2L refrigerants.

R454B Physical Properties

Property R454B Value
Chemical classification HFC/HFO Zeotropic Blend
Components R-32 (68.9%) + R-1234yf (31.1%)
Trade names Opteon™ XL41 · Puron Advance® · Solstice® 454B
Molecular weight 62.6 g/mol
Boiling point (1 atm) −58.9 °F (−50.5 °C)
Critical temperature 172.6 °F (78.1 °C)
Critical pressure 763.9 psia
Critical density 27.7 lb/ft³
Liquid heat of vaporization (at bp) 52.7 BTU/lb
Vapor density (at bp) 0.2 lb/ft³
Global Warming Potential (GWP) 466 (vs R410A: 2,088)
Ozone Depletion Potential (ODP) 0
ASHRAE 34 safety class A2L (mildly flammable)
Lower Flammability Limit (LFL) 11.3% by volume
Burning velocity <10 cm/s
Lubricant compatibility POE (Polyolester) oil required
Refrigerant cylinder color (AHRI) Medium blue (Pantone 2935C)

R454B vs R410A: Side-by-Side Comparison

Most new commercial chillers and HVAC equipment shipping after January 2025 are factory-charged with R454B. Understanding the differences helps engineers plan retrofits and new installations correctly.

Parameter R454B R410A
GWP 466 2,088
ODP 0 0
ASHRAE safety class A2L A1
Operating pressure (80 °F) ~293 psig ~278 psig
Cooling capacity (relative) ≈ Equal Baseline
Energy efficiency 5–12% better COP Baseline
Temperature glide ~1.5 °F ~0.1 °F (near-azeotropic)
EPA AIM Act status (2025+) ✔ Approved for new equipment ✘ Banned in new equipment
Drop-in replacement? Not a direct drop-in —
Retrofit requirement POE oil flush, A2L components —
Gauge set required A2L-certified gauges Standard gauges

Important: R454B is not a direct drop-in for R410A. Retrofitting an existing R410A system requires flushing the mineral or alkylbenzene oil and replacing it with POE lubricant, verifying component pressure ratings, and installing A2L-compliant leak detection where required by local code. For new chiller installations, factory configuration for R454B is the cleanest path.

Geson Chillers Compatible with R454B

Geson’s engineering team has been factory-configuring chiller systems with R454B since 2023, ahead of the EPA mandate. The following product lines are available with R454B as the standard or optional refrigerant:

  • Air-Cooled Scroll Chillers (3–50 Ton) — standard R454B configuration available; A2L-compliant scroll compressors, POE-filled from factory, A2L leak detection fitted as standard.
  • Air-Cooled Screw Chillers (50–500 Ton) — R454B optional; specify at order stage. Factory pressure-tested at 1.1× maximum operating pressure.
  • Water-Cooled Scroll Chillers (10–200 Ton) — R454B standard on all units built after Q1 2024.
  • Industrial Process Chillers — R454B available for process temperature ranges of −10 °C to +25 °C. For low-temperature process applications below −10 °C, consult Geson engineering for alternative low-GWP refrigerant options (R448A, R449A).

All Geson R454B chiller units ship with factory charge, pre-delivery pressure test documentation, and refrigerant charge weight recorded on the nameplate. Lead time: 15 working days standard.

Need a chiller specified for R454B? Send your cooling load (tons or kW), process temperature, and ambient conditions to our engineering team and we will return a formal quotation within 24 hours.

Request a Quote for R454B Chiller →

R454B Safety and Handling

R454B carries an A2L classification under ASHRAE Standard 34, meaning it is mildly flammable with a burning velocity below 10 cm/s and a Lower Flammability Limit of 11.3% by volume. This is significantly less flammable than A3 refrigerants such as propane (R290), but it does require specific precautions that were not necessary with A1 refrigerants like R410A:

  • Use only A2L-certified manifold gauges and recovery equipment.
  • Install A2L-rated refrigerant leak detectors in enclosed equipment rooms — required by many local codes for systems over 3 kg charge.
  • Ensure adequate ventilation: minimum 0.5 air changes per hour in mechanical rooms containing R454B systems.
  • Do not use open flames or create ignition sources when working on charged systems.
  • Technicians handling R454B must hold EPA Section 608 certification (Universal or Type II minimum).
  • Recovery cylinders must be rated for R454B — never mix with recovered R410A.

Frequently Asked Questions about R454B

What is R454B refrigerant?

R454B is a low-GWP HFC/HFO zeotropic refrigerant blend made from 68.9% R-32 and 31.1% R-1234yf. It has a GWP of 466 — 78% lower than R410A — and an ASHRAE A2L (mildly flammable) safety rating. It is the primary replacement refrigerant mandated by the U.S. EPA AIM Act for new residential and commercial AC systems from January 1, 2025.

Is R454B the same as R410A?

No. R454B and R410A have different compositions, pressure-temperature profiles, and safety classifications. R410A is an A1 (non-flammable) near-azeotropic blend; R454B is an A2L (mildly flammable) zeotropic blend. Their operating pressures are similar but not identical — R454B runs approximately 5% higher at the same temperature. They cannot be mixed and R454B is not a direct drop-in replacement.

Can I retrofit my R410A chiller to use R454B?

In most cases, a full retrofit is not recommended. R454B requires POE lubricant (incompatible with the mineral oil used in many older R410A systems), A2L-compliant components, and leak detection upgrades. For most aging R410A chillers, replacing with a new R454B-native unit delivers better efficiency and lower long-term service cost than a retrofit.

What is the pressure of R454B at 90 °F?

At 90 °F (32.2 °C), R454B has a bubble point pressure of approximately 348 psig and a dew point pressure of approximately 337 psig. Always use the dew point for suction-side diagnosis and bubble point for liquid-line measurements due to the refrigerant’s temperature glide.

What oil does R454B require?

R454B requires Polyolester (POE) oil. The correct viscosity grade depends on the compressor type and operating temperature range — typically ISO 32 or ISO 46 for scroll compressors, and ISO 68 for screw compressors. Always confirm with the compressor manufacturer’s specification sheet.

What are the trade names for R454B?

R454B is sold under three main trade names: Opteon™ XL41 (Chemours), Puron Advance® (Carrier), and Solstice® 454B (Honeywell). All three are the same refrigerant blend — 68.9% R-32 and 31.1% R-1234yf.

Is R454B flammable?

R454B has an ASHRAE A2L classification, meaning it is mildly flammable. Its Lower Flammability Limit is 11.3% by volume and its burning velocity is less than 10 cm/s. For comparison, propane (A3) ignites at 2.1% concentration. R454B poses minimal flammability risk under normal operating conditions, but A2L-certified tools and leak detection are required by code in most jurisdictions.

What is the GWP of R454B?

R454B has a Global Warming Potential (GWP) of 466, calculated over a 100-year period relative to CO₂. This compares to 2,088 for R410A and 1,430 for R134a. The low GWP is the primary reason the EPA selected R454B-class refrigerants as the preferred next-generation option under the AIM Act.

Does Geson manufacture chillers with R454B?

Yes. Geson has been producing R454B-charged chiller systems since 2023. Air-cooled scroll chillers (3–50 ton) and water-cooled scroll chillers (10–200 ton) ship with R454B as standard. Screw chiller configurations with R454B are available on request. Contact our engineering team with your cooling requirements for a formal quotation.

What gauge pressure should I expect on the high side of an R454B system?

At a typical condensing temperature of 110–120 °F (43–49 °C), expect high-side pressures in the range of 480–560 psig. This is slightly higher than the equivalent R410A system. Confirm that all pressure-side components (compressor, condenser, piping) are rated for a minimum of 650 psig working pressure when working with R454B.

Geson Chiller Product Line

All models below are available with R454B factory configuration. Contact our engineering team with your cooling load and application requirements for a formal quotation.

Contact us today for industrial cooling solutions that will suit your needs and budget.

Related Resources