If you service freezers or cold rooms, chances are you’ve worked with R507A before. For years, many technicians relied on it for dependable low-temp performance. But with today’s environmental regulations, many contractors and facility owners are now switching to lower-GWP options.
In this guide, you’ll learn what R507A refrigerant is, where it’s used, its pros and cons, and which refrigerants can replace it today.
What is R507A Refrigerant?
R507A (often abbreviated as R507) is an HFC refrigerant blend widely used in low-temperature systems. R507A is an azeotropic blend of R125 (pentafluoroethane) and R143a (trifluoroethane), each comprising 50% by mass. Since it contains no chlorine, it does not harm the ozone layer. That made it a popular replacement for older refrigerants with zero ODP. R507A was developed primarily to replace traditional refrigerants that deplete the ozone layer, especially R502 in low-temperature systems.
Properties of R507A Refrigerant
Physical Properties
R507A has a boiling point much lower than that of conventional medium-temperature refrigerants. You’ll often see it in systems that run below -40°C. That is why it works well in freezer applications.
In terms of density, R507A has a high liquid density, meaning that a storage tank of the same volume can hold more refrigerant, which can reduce storage space needs. Its moderate vapour density results in low flow resistance within refrigeration piping, which can reduce compressor strain. It also has relatively high pressure at room temperature.
Therefore, specialised high-pressure cylinders must be used for storage to prevent internal pressure from exceeding safe limits because of exposure to high temperatures.
One major characteristic of R507A is its zero glide. As an azeotropic refrigerant blend, its gas and liquid phase compositions remain consistent throughout the evaporation and condensation processes, eliminating the temperature drift phenomenon seen in non-azeotropic refrigerants. This helps maintain stable system performance.
R507A is insoluble in water but fully miscible with POE (polyester) lubricants. This helps keep the compressor properly lubricated, preventing failures caused by oil blockages or insufficient lubrication. It also facilitates lubricant replacement and refrigerant recharge during system maintenance.
The R507A properties are listed below:
| Features | R507A |
| Formula | 50% R-125 (Pentafluoroethane) 50% R-143a (1,1,1-Trifluoroethane) |
| Chemical Formula | CH3CF3 & CHF2CF3 |
| Type | HFC Refrigeration |
| Molecular weight (g/mol) | 98.9 |
| Boiling Temperature (1 atm, °F) | -52.1 |
| Critical Temp (°F) | 159.8 |
| Critical Pressure （bar） | 537.3 |
| Critical Density (lb./ft ^3) | 30.7 |
| Vapour Density (bp, lb./ft ^3) | 0.349 |
| Liquid Density (0°C, kg/m³) | 1047.9 |
| Gaseous Density (25°C, kg/m³) | 68.89 |
| Heat of Vaporisation (bp, BTU/lb.) | 84.35 |
| Global Warming Potential | 3985 |
| Ozone Depletion Percentage | 0 |
| ASHRAE Safety Group | A1 |
| Toxicity | Non-toxic |
| Flammability | Non-flammable |
| Oil | POE |
Chemical Properties
R507A exhibits strong chemical stability. Under normal temperature and pressure conditions, when stored in a sealed container away from light, it does not decompose spontaneously. It also does not react with air or common metals. It is non-corrosive to metals commonly used in refrigeration systems, such as carbon steel, stainless steel, and copper. This is a key reason why it is compatible with various types of refrigeration compressors, heat exchangers, and piping.
However, it is important to note that it must not come into direct contact with reactive metals such as aluminium-magnesium alloys, zinc, alkali metals, and alkaline earth metals. Prolonged contact can cause chemical reactions that damage equipment components. Therefore, these materials must be strictly avoided when selecting system components.
R507A is a good fit for medium and low-temperature refrigeration applications. However, at temperatures exceeding 400°C, R507A undergoes thermal decomposition, releasing toxic and harmful gases such as hydrogen fluoride and carbon dioxide.
This not only pollutes the environment but can also cause burns to the respiratory tract and skin. Therefore, during operation, you must keep the refrigerant away from open flames and high-temperature heat sources to avoid the risk of high-temperature decomposition.
R507A Refrigerant Pressure Temperature Chart
Use this R507A pressure temperature chart when checking suction pressure, head pressure, or system charging conditions.
| R-507 (PSIG) | ℉ | ℃ |
| 5.5 | -40 | -40 |
| 8.2 | -35 | -37.2 |
| 11.1 | -30 | -34.4 |
| 14.3 | -25 | -31.7 |
| 17.8 | -20 | -28.9 |
| 21.7 | -15 | -26.1 |
| 25.8 | -10 | -23.3 |
| 30.3 | -5 | -20.6 |
| 35.2 | 0 | -17.8 |
| 40.5 | 5 | -15 |
| 46.1 | 10 | -12.2 |
| 52.2 | 15 | -9.4 |
| 58.8 | 20 | -6.7 |
| 65.8 | 25 | -3.9 |
| 73.3 | 30 | -1.1 |
| 81.3 | 35 | 1.7 |
| 89.8 | 40 | 4.4 |
| 98.9 | 45 | 7.2 |
| 109 | 50 | 10 |
| 119 | 55 | 12.8 |
| 130 | 60 | 15.6 |
| 141 | 65 | 18.3 |
| 154 | 70 | 21.1 |
| 167 | 75 | 23.9 |
| 180 | 80 | 26.7 |
| 195 | 85 | 29.4 |
| 210 | 90 | 32.2 |
| 226 | 95 | 35 |
| 244 | 100 | 37.8 |
| 262 | 105 | 40.6 |
| 281 | 110 | 43.3 |
| 301 | 115 | 46.1 |
| 322 | 120 | 48.9 |
| 344 | 125 | 51.7 |
| 368 | 130 | 54.4 |
| 393 | 135 | 57.2 |
| 419 | 140 | 60 |
| 446 | 145 | 62.8 |
| 475 | 150 | 65.6 |
Advantages of R507A Refrigerant
As a classic refrigerant in the medium- and low-temperature refrigeration sector, R507A refrigerant has remained popular for years in low-temperature refrigeration. If you use it in real life, these benefits can lower costs and simplify operations.
Excellent Refrigeration Performance
The cooling capacity and energy efficiency ratio of R507A refrigerant are very close to those of the traditional R502 refrigerant. Under certain operating conditions, it even outperforms R404A. Under the same refrigeration conditions, compared to the traditional R22 refrigerant, R507A delivers a higher capacity by 7%–13%.
In low-to-medium temperature refrigeration cycles, it offers high heat exchange efficiency and rapid cooling, reliably meeting low-temperature refrigeration requirements ranging from -40°C to -5°C.
Because of zero temperature drift, temperature fluctuations during system operation are minimal. That matters in places like food storage and pharma cooling, making it a reliable choice for demanding applications.
High System Compatibility
Designed specifically to replace R502, this refrigerant offers strong compatibility with existing R502 and R22 refrigeration systems. There is no need to replace core equipment such as compressors or heat exchangers. Simply replace the existing lubricant in the system with POE lubricant.
After a proper oil change and system checks, many retrofits can be completed with minimal changes. This reduces the time and cost associated with equipment retrofitting. Whether for new installations or retrofitting older systems, it works well in many retrofit systems.
Safety
R507A refrigerant is an ASHRAE A1 refrigerant —non-toxic and non-flammable—with extremely low safety risks during daily operation, storage, and transportation. Its azeotropic blend that helps keep the composition stable during operation. This prevents efficiency losses and frequent malfunctions caused by component separation.
It has excellent miscibility with dedicated lubricants, effectively ensuring compressor lubrication, reducing equipment wear, extending the service life of core components, and simplifying daily maintenance.
Environmental Protection
R507A refrigerant has an ODP value of 0 and does not deplete the ozone layer. However, its GWP of 3,985 is considered high by today’s standards.
Disadvantages of R507A Refrigerant
No refrigerant is perfect. Given current trends in the refrigeration industry, R507A also has significant limitations. You must fully consider these shortcomings during selection to avoid subsequent operational and compliance risks.
High GWP
The GWP of R507A refrigerant is as high as 3,985, far exceeding the limits set by current environmental regulations. Many countries and regions have already implemented policies restricting the use of high-GWP refrigerants. For example, the EU’s F-Gas Regulation restricts the use of refrigerants with a GWP > 2,500, while the U.S. EPA’s SNAP program encourages the phase-out of R507A. You could face compliance issues as regulations tighten.
High Long-Term Operating Costs
Due to gradual global production cuts and phase-outs, the market supply of R507A continues to decrease, and prices have increased as supply tightens. Furthermore, increasingly stringent requirements for recovery and disposal add to the operational and recovery costs of the refrigerant. Compared to new low-GWP refrigerants, the long-term economic viability of R507A has declined, which will increase your project costs.
Proper Charging Matters
R507A has a stable blend ratio, but proper charging procedures still matter. Good service practices help maintain performance and prevent contamination. Therefore, during charging and maintenance, you must engage qualified professionals to strictly follow operating procedures to help ensure consistency in the mixture ratio.
Where is R507A Refrigerant Used?
R507A refrigerant is a good fit for any application requiring low-to-medium temperature refrigeration:
- Commercial Refrigeration: Walk-in freezers, display freezers, cold rooms, ice cream equipment
- Industrial Refrigeration: Large-scale industrial cold storage facilities, chemical industry low-temperature cooling systems, and low-temperature testing equipment
- Cold Chain: Reefer trucks, refrigerated containers, marine refrigeration equipment
- Pharmaceuticals: Low-temperature drug storage, vaccine refrigeration, and biological sample freezing equipment
- Specialised applications: Lab freezers
If you have equipment using R507A refrigerant, it can still operate normally. However, you should maintain leak control and follow local regulations.
What are the alternatives to R507A refrigerant?
Because R507A has a high GWP, many lower-GWP replacements are now available. You can select the appropriate alternative based on your system configuration, budget, and environmental requirements.
R448A
R448A is one of the most common lower-GWP replacements used to replace R507A and R404A. With a GWP of just 1,390, it is much lower than that of R507A. Its ODP is 0, demonstrating excellent environmental performance. Its cooling performance is comparable to R507A, yet it offers higher energy efficiency. In many retrofit jobs, you can use it to replace R507A with limited changes.
You only need to switch to a compatible lubricant, making it the preferred alternative for commercial and industrial low-to-medium temperature refrigeration systems, with strong adaptability.
R449A
R449A is a low-GWP, zero-ODP refrigerant with a GWP value of approximately 1,357. Its performance parameters closely match those of R507A, with similar operating pressures and cooling capacities, making it easy to replace and retrofit. Because it runs efficiently and stays stable, you could use it.
It is suitable for applications such as supermarket cold storage and cold chain transportation. Additionally, it is highly safe, non-toxic, and non-flammable, which helps reduce operating and maintenance risk. It can be a practical short-term replacement option.
R452A
R452A has a GWP of 2,140, placing it between traditional refrigerants and ultra-low GWP refrigerants. It offers high ease of replacement and may be used with limited system changes in existing R507A systems. You do not need to make significant modifications to your equipment. In many systems, it runs efficiently and stays stable. For scenarios where you wish to meet basic environmental requirements without incurring high retrofitting costs, it is an excellent compromise solution.
R1234yf
R1234yf is a refrigerant with an extremely low GWP value of just 4. It was initially used primarily in automotive air conditioning, but in recent years has also begun to be adopted in commercial air conditioning and refrigeration systems. R1234yf offers excellent environmental and thermodynamic performance, making it a promising alternative to R507A refrigerant.
However, it requires targeted modifications to existing refrigeration systems, including the use of specialised compressors and lubricants. The initial retrofit costs are relatively high, making it suitable for new refrigeration projects or long-term upgrades of older systems. It meets some of today’s strictest environmental standards.
The Quick Comparison:
| Refrigerant | GWP | Best For |
| R448A | 1390 | Retrofit |
| R449A | 1357 | Supermarkets |
| R452A | 2140 | Transport |
| R1234yf | 4 | New systems |
Wrapping It Up
R507A still works well in many freezer systems. But because its GWP is high, more buyers are switching to newer refrigerants. If you’re planning a retrofit or new project, this is a good time to compare newer options and cut future costs.
If you’re upgrading a cold room, freezer system, contact Sunnyda for expert refrigerant recommendations, retrofit support, and bulk pricing.
FAQ
Is R507A being phased out?
Yes. Many regions are reducing the use of R507A because of its high GWP.
Can R448A replace R507A?
Yes. R448A is one of the most common lower GWP replacements.
Is R507A better than R404A?
In many low-temp systems, R507A performs similarly to or better than R404A.
Is R507A banned?
No. You should pay attention to the laws of your location. Some countries are phasing it down and reducing its use.
What is the difference between 404A and R507A?
R507A is an azeotropic mixture composed of R125 and R143a that behaves similarly to a pure fluid, while R404A is a near-azeotropic mixture composed of R125, R143a, and R134a.
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