Refrigerant is the chemical substance used in air conditioners. It absorbs environmental heat and releases cool air after passing through the evaporators and compressors.
Refrigerants are necessary for HVAC (heating, ventilation, and air conditioning) systems to perform the vital heat transfer process that generates both heating and cooling.
Over time, the evolution of technology and growing environmental consciousness have led to a substantial shift in the types of refrigerants used in HVAC systems. And it is simple to confuse them given there are various types of refrigerants.
Additionally, choosing the wrong kind could damage and harm air conditioners as they are not interchangeable. In light of this, it is crucial to get as much knowledge as possible regarding these refrigerants.
Types of Refrigerants
1. R2
R22, referred to as freon, is one of the earliest types of refrigerants and is frequently found in air conditioner units that are older than ten years. The compound is produced from chloroform and hydrogen fluoride.
It is favored over other refrigerants due to its effective cooling qualities and less flammability. As a transitional replacement for chlorofluorocarbons (CFCs) like R12, hydrochlorofluorocarbons (HCFCs) including R22 were developed because of their lesser tendency to deplete the ozone layer.
However, it still poses significant environmental concern contributing to both ozone layer depletion and global warming.
Given R22 leaks are toxic and can harm the environment - due to its substantial risk it poses to the ozone layer and public health, the Clean Air Act of 2010 was passed, and manufacturers have ceased to use it.
Consequently, in 2010 its import and manufacture were further restricted. Furthermore, R22 will only be available in recovered, recycled, or reclaimed sources after it is no longer produced in the 2020s.
2. R410A
R410A is composed of two hydrofluorocarbons (HFCs): pentafluoroethane - R125 and difluoromethane - R32. Also known as puron, this refrigerant is referred to as the replacement of R22 for air conditioners.
While still maintaining the same cooling characteristic as mentioned refrigerant, it is thought to be less hazardous due to chlorine’s lack of presence in the mixture.
Furthermore, compared to R22, R410A powered systems are said to be more energy-efficient, provide superior air quality, boost comfort, and do not deplete the ozone layer.
A limitation is found, nevertheless, in that it cannot be applied to a system that has previously operated on R22. Hence, it most likely needs to be upgraded or replaced (anderWorker, 2023).
And while it does not bring harm to the ozone layer, another issue arises as it has a high global warming potential (GWP), which significantly contributes to global warming.
3. R134A
Also referred to as tetrafluoromethane, R134A is one of the forms of refrigerant that air conditioners use the most commonly throughout the world. Given its characteristic that it is non-toxic, non-flammable, and non-corrosive, it is safe for common handling.
Additional positive point is that hydrofluorocarbons (HFCs) have not been directly linked to any negative effects on the environment, particularly in terms of the depletion of the ozone layer.
Subsequent refrigerants that contained an extra chlorine atom significantly caused massive depletion to the ozone layer. In light that R134A does not contain chlorine atoms, it is considered to be a superior alternative for R22 and R410A.
However, it is asserted to have a great potential for global warming. Thus, R134A is already being replaced across industries with hydrofluorocarbon replacements that have a lower global warming potential.
4. R32
R32 is an organic hydrofluorocarbon molecule, also referred to as difluoromethane. It is a water-soluble gas that is colorless, odorless, and mildly flammable.
Difluoromethane is typically utilized in a range of HVAC applications, primarily for residential and commercial air conditioning, including portable air conditioners and window units (Coils, 2024).
These refrigerant permits systems that contain it to operate more energy-efficiently and to consume a quarter less refrigerant gas than R410A while maintaining equivalent consumptions (Borz, 2018).
Ever since the freon ban was implemented, R32 has taken its place for replacement. This is regarded as a safer and better option for air conditioners. In fact, this gas is what most modern air conditioners run on. Furthermore, compared to R22, R32 has a far less effect on the environment and ozone layer.
5. R407C
R407C is a hydrofluorocarbons (HFCs) type and shares most of the same characteristics as R22. It is used as a substitute for R22 in air conditioning systems and medium temperature refrigeration applications, possesses an A1 safety classification and is a non-flammable refrigerant.
This refrigerant is suitable for use in brand-new machinery and is primarily worked in industrial, commercial, and residential air conditioning systems. By replacing the oil, it can also be used to retrofit some outdated R22 systems.
Additionally, this refrigerant also employs polyolester (POE) oil, a kind of wax free synthetic oil that is used in refrigeration compressors and is compatible with R134A and R410A among other refrigerants.
6. R717
Ammonia, also referred to as R717, is a naturally occurring refrigerant. It is a grade of ammonia - NH3 refrigerant that is well-known for having excellent heat transfer qualities and efficiency in applications at low and medium temperatures. This makes it ideal for extensive and large-scale refrigeration systems.
Despite being extremely toxic, colorless, and pungent, it is exceptionally an effective refrigerant with zero global warming potential (GWP) and ozone depletion potential (ODP), making it safe for the environment.
Furthermore, ammonia's toxicity and flammability necessitate stringent technical controls and safety procedures in its application, much like hydrocarbons do (Connor, 2024).
ODP and GWP Summary
Refrigerant Type | Ozone Depletion Potential (ODP) | Global Warming Potential (GWP) |
R22 | 0.05 | 1810 |
R410A | 0 | 2088 |
R134A | 0 | 1430 |
R32 | 0 | 675 |
R407C | 0 | 1774 |
R717 | 0 | 0 |
Conclusion
In the battle against ozone depletion and climate change, switching from environmentally damaging refrigerants like chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) to more sustainable alternatives are crucial.
The specific characteristics of each type of refrigerant affect its effects on the environment, system design, and safety specifications. Comprehending these characteristics aids in the selection of suitable refrigerants that satisfy environmental rules as well as operational requirements.
TCW Group is a one stop HVAC manufacturer based in Malaysia. We offer a range of services from custom application-based unit design to production and final unit assembly.
Shall you have any inquiries, please reach us at info@tcw-my.com
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