R454A Refrigerant35/65 R32/R1234yf · Opteon XL40 · Low/medium-temperature refrigeration
R454A is an A2L zeotropic blend of 35% R32 and 65% R1234yf designed mainly for low- and medium-temperature commercial and industrial refrigeration. Compared with R404A it delivers a dramatic GWP reduction while maintaining broadly similar refrigeration duty. Its approximately 5 K glide and A2L classification make it a new-equipment / redesign refrigerant rather than a simple A1 drop-in.
What is R454A refrigerant?
R454A is an R32/R1234yf blend positioned as a lower-GWP R404A-class refrigerant. EPA’s current GWP is 237. It is SNAP-listed subject to use conditions in new supermarket, remote-condensing, cold-storage and industrial-process applications, with some end uses also imposing charge or cascade restrictions.
R454A refrigerant properties
Use these values for research and screening. For equipment design, charging and compliance, use the exact supplier PT data, SDS, OEM documentation and regulation that governs the project.
| Property | Reference | Engineering / source note |
|---|---|---|
| Designation | R454A | ASHRAE designation / Opteon XL40 |
| Nominal composition | R32/R1234yf = 35/65 mass % | Chemours / published data |
| Refrigerant type | Zeotropic HFC/HFO blend | Two components |
| Molecular weight | ≈80.5 g/mol | Chemours |
| Normal bubble point | ≈ −47.8°C | Chemours |
| Dew point near 1 atm | ≈ −42.2°C | Published data |
| Temperature glide | ≈5 K | Chemours |
| Critical temperature | ≈81.7°C | Chemours |
| ODP | 0 | No ozone depletion |
| 100-year GWP | 237 | EPA Technology Transitions |
EPA Technology Transitions uses the values shown on this page. Older product literature may use IPCC AR4/AR5 or another assessment, so a different number is not automatically an error.
Where is R454A used?
Applications must be evaluated by system type, charge, compressor, heat exchanger, safety class and current regulation. The examples below describe recognized use contexts, not automatic approval for every installation.
Supermarket systems
EPA SNAP Rule 26 lists R454A for new equipment subject to use conditions.
Remote condensing units
Used in new A2L-compatible low/medium-temperature systems subject to use conditions.
Cold-storage warehouses
EPA permits R454A in new systems under specified conditions, including equipment/charge limitations.
Industrial process refrigeration
EPA lists R454A for new IPR equipment subject to use conditions.
Positive-displacement chillers
R454A is SNAP-listed for new chillers subject to A2L use conditions.
Residential / light-commercial HVAC
EPA also listed R454A in new residential/light-commercial AC / heat-pump equipment under Rule 23 use conditions.
Continue through the Refrigerant Replacements and Low-GWP Refrigerants hubs for broader selection context.
R454A and R454C use the same two components—but at very different ratios
R454A contains 35% R32 and 65% R1234yf. R454C shifts much farther toward R1234yf at 21.5% R32 and 78.5% R1234yf.
The higher R32 fraction in R454A raises capacity and GWP while reducing some of the extreme glide seen in R454C.
This illustrates how blend composition can tune thermodynamic performance and climate impact even when the component list is identical.
Why R454A is closer to R404A performance than its GWP suggests
Chemours positions R454A specifically for R404A-designed low/medium-temperature refrigeration. Its pressure/capacity characteristics can allow smaller equipment changes than moving to a completely different architecture.
Experimental refrigeration studies have reported improved COP versus R404A under specific test conditions, but those results are test-specific and should not be generalized into a guaranteed energy saving.
Compressor envelope, discharge temperature, expansion device and heat exchangers still require refrigerant-specific validation.
The ~5 K temperature glide is an engineering variable, not a footnote
R454A has materially more glide than R404A. The evaporating and condensing temperature profile therefore changes across the heat exchanger.
Correct bubble/dew references must be used for service calculations and controller setup. The glide can be beneficial in well-matched counterflow heat exchangers but can also complicate traditional control assumptions.
Charging and leak servicing should follow zeotropic-blend procedures.
EPA Rule 26 includes application-specific R454A restrictions
EPA’s Rule 26 listings are not a blanket 'approved everywhere' statement. For some industrial-process, cold-storage, supermarket and remote-condensing applications, R454A use is tied to equipment charge or high-side cascade conditions.
EPA proposed/final Rule 26 materials include conditions such as refrigerant charge below specified amounts or use on the high-temperature side of a cascade in certain categories.
Designers should therefore open the exact SNAP end-use table and rule conditions rather than relying only on the refrigerant’s GWP.
R454A vs R454C
The table highlights engineering differences rather than implying direct interchangeability.
| Characteristic | R454A | R454C |
|---|---|---|
| Composition | R32/R1234yf = 35/65 | R32/R1234yf = 21.5/78.5 |
| EPA GWP | 237 | 146 |
| Safety class | A2L | A2L |
| Temperature glide | ≈5 K | Higher, around 8 K endpoints near 1 atm |
| R32 fraction | 35% | 21.5% |
| Typical goal | R404A-class performance with lower GWP | Sub-150 long-term refrigeration |
| Regulatory margin below 150 | No | Yes |
R454A safety: lower GWP requires A2L-compatible refrigeration design
R454A is A2L. A system designed for A1 R404A cannot be assumed suitable for it. Equipment listing, permitted charge, ignition-source control, ventilation, service tools and any required detection/mitigation must follow the relevant A2L standard and EPA use conditions.
A2L charge control
System charge and occupied volume may drive additional requirements.
Ignition sources
Electrical components and hot surfaces must be evaluated for the listed equipment design.
Blend service
Use R454A PT data and liquid/blend charging practice.
Actual risk depends on charge, release rate, pressure, room volume, ventilation, ignition sources, equipment construction, alarm logic and service condition.
See the Refrigerant Safety Guide for classification context.
R454A refrigerant leak detection
Validate detector response to the finished blend
Use R454A-specific or explicitly validated A2L blend detection. The public GasNose directory does not currently list a dedicated R454A page, so this profile links to the general refrigerant-gas detection library rather than inventing a page URL. Sensor selection should distinguish between service leak finding and fixed mitigation.
Portable service leak detectors, fixed area monitors, A2L mitigation sensors and refrigerant identifiers perform different functions. Define the alarm action and concentration range before selecting the technology.
Regulatory position of R454A in 2026
United States
EPA lists R454A in new residential/light-commercial AC and heat pumps, chillers, industrial process AC and several new commercial/industrial refrigeration end uses subject to A2L use conditions. Rule 26 imposes additional application-specific conditions for some cold-storage, supermarket, remote-condensing and industrial-process installations. EPA Technology Transitions GWP is 237.
European Union
R454A is far below R404A but remains above 150. It may fit some transitional EU F-gas pathways while later restrictions in selected commercial refrigeration categories favor sub-150 or non-fluorinated refrigerants.
Is R454A being phased out?
R454A is a strong lower-GWP new-equipment option where A2L is acceptable, but its GWP 237 gives less long-term regulatory margin than sub-150 blends such as R454C, R455A or R516A.
U.S. refrigeration limits differ by cold storage, supermarket, remote condensing, stand-alone product, industrial process and chiller category. A refrigerant may fit one pathway and fail another.
Use the Refrigerant Regulations Hub for regional research.
What should be compared with R454A?
Compare the real equipment pathway: retrofit vs new system, A1 vs A2L capability, GWP threshold, glide, compressor envelope, energy efficiency and service ecosystem.
Practical misconceptions about R454A
“R454A and R454C are interchangeable.”
They use the same components at different ratios and have different GWP, glide and capacity.
“R454A is an A1 R404A retrofit.”
R454A is A2L and equipment must be designed/approved accordingly.
“GWP 237 means every U.S. refrigeration use is unrestricted.”
SNAP use conditions can impose charge/cascade and equipment-standard requirements.
“The glide can be ignored.”
About 5 K of glide is large enough to affect PT calculations and heat-exchanger behavior.
R454A refrigerant FAQ
Concise answers to common composition, retrofit, glide, safety and regulation questions.
What is R454A?
What is the EPA GWP of R454A?
Is R454A flammable?
Does R454A have temperature glide?
Can R454A replace R404A?
What is the difference between R454A and R454C?
Is R454A SNAP-approved?
Does R454A meet a 150-GWP limit?
Can R454A be used in cold storage?
How should R454A leaks be detected?
R454A sources and further reading
This profile uses current EPA regulatory references plus refrigerant supplier, NIST, scientific and GasNose resources. Re-check the latest edition before design or compliance decisions.
Working with R454A or planning a refrigerant transition?
Compare GWP, safety class, temperature glide, equipment compatibility and regulatory lifetime before selecting a refrigerant.
Technical Notice: This page is for refrigerant research and general technical reference. Refrigerant suitability, permitted charge, equipment approval, leak mitigation, servicing procedures and regulatory compliance depend on the exact equipment, installation and jurisdiction. Always verify current manufacturer documentation, SDS, applicable standards and local regulations before selecting, replacing, charging or servicing a refrigerant.