R452A Refrigerant11/59/30 R32/R125/R1234yf · Opteon XP44 · Transport refrigeration specialist
R452A is a zeotropic A1 blend of 11% R32, 59% R125 and 30% R1234yf by mass. It was designed to replace R404A/R507A while preserving similar compressor discharge temperature and mass-flow behavior—an important advantage in transport refrigeration exposed to wide ambient conditions. Its EPA GWP of 2,140 is lower than R404A but still high enough that new transport and stationary regulations are now driving another transition.
What is R452A refrigerant?
R452A is best understood as an R404A-class transition refrigerant optimized around transport and low-temperature equipment. It combines an A1 safety rating with compressor behavior close to R404A/R507A. EPA SNAP lists it for refrigerated trucks and trailers, but Technology Transitions restrictions mean its long-term new-equipment role is limited by GWP.
R452A 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 | R452A | ASHRAE designation / Chemours Opteon XP44 |
| Nominal composition | R32/R125/R1234yf = 11/59/30 mass % | Chemours retrofit guidance |
| Refrigerant type | Zeotropic HFC/HFO blend | Three components |
| Average molecular weight | ≈103.5 g/mol | Chemours |
| Bubble boiling point at 1 atm | ≈ −47.0°C | Chemours |
| Dew point at 1 atm | ≈ −43.1°C | Published R452A property data |
| Critical temperature | ≈74.9°C | Chemours |
| Critical pressure | ≈40.0 bar | Chemours |
| ODP | 0 | No ozone depletion |
| 100-year GWP | 2,140 | EPA Technology Transitions / AR4 basis |
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 R452A 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.
Road transport refrigeration
Refrigerated trucks and trailers are the signature R452A application.
Reefer / intermodal equipment
Used in transport DX systems, though new intermodal equipment will face a 700-GWP U.S. limit from July 27, 2027 for specified temperature ranges.
Low-temperature commercial DX refrigeration
Chemours positions R452A for compatible R404A/R507A equipment.
Medium-temperature commercial refrigeration
Applicable in selected direct-expansion systems.
Industrial DX refrigeration
Used where R404A-class capacity and discharge-temperature behavior are important.
R404A/R507A retrofit
A major retrofit route because the refrigerant was engineered to resemble legacy compressor behavior.
Continue through the Refrigerant Replacements and Low-GWP Refrigerants hubs for broader selection context.
Why R452A became important in transport refrigeration
Transport equipment experiences large ambient-temperature swings, vibration, compact heat exchangers and strict compressor operating limits. R452A was designed to keep discharge temperature and mass flow close to R404A/R507A.
Chemours specifically highlights refrigerated trucks, vans and reefer containers as target applications and notes that R452A can reduce the need for major TXV changes in qualified systems.
That historical fit explains why R452A can remain attractive for servicing or certain existing platforms even though newer regulations now demand much lower GWP.
R452A glide: more than R404A, less than many modern blends
Published R452A data show a bubble point near −47.0°C and dew point near −43.1°C at atmospheric pressure—about 3.9 K endpoint separation.
This is large enough that superheat/subcooling calculations should use the correct saturation endpoint, but much smaller than the extreme glide of R455A.
Heat-exchanger and controller settings should therefore use R452A PT data rather than R404A assumptions.
R404A/R507A retrofit engineering
Chemours’ retrofit procedure identifies R452A as suitable for many positive-displacement, direct-expansion low- and medium-temperature R404A/R507A systems.
Component checks still matter: compressor approval, oil, seals, filter-drier, charge, control setpoints and leak condition should be evaluated before conversion.
R452A can be topped off after leaks according to Chemours’ product guidance, but the system should still be assessed for contamination or major composition loss after significant leakage.
Why R452A is already facing a second refrigerant transition
R452A reduced climate impact compared with R404A, but EPA’s current GWP is still 2,140—far above many new-equipment thresholds.
EPA Technology Transitions prohibits listed high-GWP refrigerants such as R404A in new road/marine refrigerated-transport products from January 1, 2025, and places a 700-GWP limit on specified intermodal-container products/systems beginning July 27, 2027.
R452A can therefore be an important service/bridge refrigerant while newer transport platforms move toward sub-700 or much lower-GWP options.
R452A vs R404A
The table highlights engineering differences rather than implying direct interchangeability.
| Characteristic | R452A | R404A |
|---|---|---|
| Composition | R32/R125/R1234yf = 11/59/30 | R125/R143a/R134a = 44/52/4 |
| EPA GWP | 2,140 | 3,922 |
| Safety class | A1 | A1 |
| Temperature glide | Moderate (~3.9 K endpoints at 1 atm) | Very small |
| Discharge temperature intent | Designed to stay close to R404A | Legacy baseline |
| Signature application | Transport refrigeration | Broad low-temp commercial refrigeration |
| Long-term new-equipment fit | Limited by high GWP | More restricted |
R452A safety: A1 with transport-specific service and blend considerations
R452A is A1. In transport equipment, service safety also includes vibration-damaged lines, hot engine compartments, confined cargo machinery spaces and recovery at variable ambient temperature. The zeotropic blend requires R452A-specific PT and charging practice.
Transport environment
Inspect vibration, hose, fitting and compressor leak points regularly.
Cold/pressure exposure
Use PPE and equipment rated for R452A pressures.
Blend control
Charge and recover according to supplier blend procedures.
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.
R452A refrigerant leak detection
Validate detector response to the finished blend
Use portable or fixed refrigerant detection compatible with R452A. GasNose lists R452A in its refrigerant directory for transport refrigeration and low-temperature equipment. Portable electronic detectors are important for fleet service, while fixed monitoring may be justified in enclosed maintenance facilities or equipment rooms.
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 R452A in 2026
United States
EPA SNAP lists R452A as acceptable in refrigerated trucks and trailers and in several stationary refrigeration end uses. Technology Transitions uses GWP 2,140. New road and marine refrigerated-transport products already prohibit a list of high-GWP legacy refrigerants from January 1, 2025; specified intermodal containers/systems operating at or above the rule’s temperature threshold move to a 700-GWP limit on July 27, 2027. R452A therefore does not fit that future 700-GWP intermodal pathway.
European Union
R452A’s GWP is lower than R404A but still above 2,000 under the AR4/EPA basis. EU F-gas quota reductions and equipment/service restrictions therefore make it a transition rather than a long-term refrigerant, particularly as transport and stationary platforms adopt much lower-GWP technologies.
Is R452A being phased out?
R452A remains useful in the installed transport and R404A/R507A service base, especially where discharge-temperature matching matters. Its high GWP means new-equipment opportunity will continue to narrow.
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 R452A?
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 R452A
“R452A is low-GWP because it is HFO-based.”
It contains 59% R125; EPA GWP is still 2,140.
“R452A has the same glide as R404A.”
R452A has materially more glide and needs bubble/dew-aware service.
“It is only for transport refrigeration.”
Transport is its signature use, but selected commercial/industrial DX systems also use it.
“Because it fits R404A equipment, it is future-proof.”
Future transport and stationary GWP limits are much lower than 2,140.
R452A refrigerant FAQ
Concise answers to common composition, retrofit, glide, safety and regulation questions.
What is R452A?
What is the composition?
What is the EPA GWP of R452A?
Why do some sources show GWP 1,945?
Is R452A flammable?
Does R452A have glide?
Why is R452A popular in transport refrigeration?
Can it retrofit R404A?
Will R452A meet the future U.S. 700-GWP intermodal-container limit?
How should R452A leaks be detected?
R452A 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 R452A 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.