The global heating, ventilation, and cooling (HVAC) industry is projected to grow; the demand for energy-efficient refrigeration and smart cooling technology is increasing due to climate change, urbanization, and population growth. R407C and R134a refrigerants are the most widely used refrigerants in the residential, commercial, industrial refrigeration industry and air conditioning systems. Choosing the right refrigerant is crucial for achieving the cooling performance needed while complying with energy conservation standards and environmental regulations. In this comprehensive guide, we will delve into the differences between R407C and R134a refrigerants, their applications, composition, features, and more.
What are R407C and R134A Refrigerant Gases?
R407C and R134a refrigerants are both hydrofluorocarbon (HFC) refrigerants, but they differ in compositions, applications, and environmental impacts.
R407C
R407C is a blend of three gases or HFC (hydrofluorocarbons) components which offer different evaporation and condensation temperatures:
R32 (difluoromethane)
R125 (Pentafluoromethane)
R134a (1,1,1,2-tetrafluoroethane)
R407C is primarily used for positive refrigeration applications (above 0°C), due to its thermodynamic properties, operating pressures, and energy efficiency, R407C maintains optimal temperatures for residential, commercial, and industrial refrigeration. R407C is a relevant alternative to R22.
R134a
R134a (tetrafluoroethane, CH₂FCF₃) is a single-component refrigerant used for medium-temperature refrigeration, process cooling, industrial air conditioning, and pharmaceutical applications. R134a is preferred for lower-pressure systems like household refrigerators and automotive air conditioning. R-134A is also known as Tetrafluoroethene (CF₃H₂F), 1,1,1,2-Tetrafluoroethane, HFC-134a, HFA-134a, and Freon 134a. R134a is developed as a replacement for R12 refrigerant.
Applications
R407C and R134A are hydrofluorocarbon (HFC) refrigerants used in cooling systems, but both of the gases they serve entirely different purposes while they operate at different pressures. R407C is used mostly in higher-pressure air conditioning and heat pumps, also, R134A is used for systems with lower-pressure requirements, when compared with R134a, R407C delivers higher heating and cooling capacity. Common applications include:
R134A
R134a is a hydrofluorocarbon refrigerant used primarily for systems designed for medium-pressure (including positive-temperature applications, high-temperature and simpler handling requirements like automotive air conditioning, car AC, household refrigerators, dehumidifiers, medium-temperature commercial refrigeration, commercial coolers, walk-in coolers, vending machines, centrifugal and screw chillers. Also, R134a is used for hot water heat pump systems.
R407C
R407C is engineered to provide efficient heating and cooling to various applications, including:
Air Conditioning
R407C is widely used in building HVAC, residential and commercial air conditioners, multi-dwelling air conditioning, centralized air conditioners, and split air conditioners.
Refrigeration Systems
R407C is used for positive refrigeration equipment such as commercial refrigeration systems, refrigeration plants, refrigerators, refrigerated display cases, and cold rooms.
Industrial Applications
R407C is suitable for applications requiring positive temperature, including industrial process cooling, air-cooled chiller units, air-to-water heat pumps, water-to-water heat pumps, heat transfer systems, and non-flooded evaporator chillers.
Composition and Properties
R407C is made of a zeotropic (azeotrope) mixture of various properties (R32, R125, and R134a), while R134a is a single component refrigerant.
R407C
R407C is a single working fluid, composed of a non-azeotropic refrigerant blend made of three different HFCs:
R32 Difluoromethane (23%)
R125 Pentafluoroethane (25%)
R134a 1,1,1,2-Tetrafluoroethane (52%)
R407C is essentially made by blending R32, R125, and R134a. R32 increases heat capacity, while R125 offers low flammability, and R134a reduces pressure. R407C is referred to as an F-gas because it belongs to the group of fluorinated greenhouse gases. Unlike pure and azeotropic fluids, R407C is a zeotropic blend of three HFCs (R-32, R-125, and R-134a), this means R407C works differently than single gases; while these three gases has a “temperature glide” or a “thermal glide” of approximately 5° to 7°C, which requires precise installation and maintenance. Also, R407C has different boiling points, while it’s boiling condensing temperatures, shifts slightly during phase changes as it boils.
R134a
R134a is a single-component hydrofluorocarbon (HFC) refrigerant with the chemical formula CH₂FCF₃, chemically known as 1,1,1,2-tetrafluoroethane. R134a is stable, non-corrosive, and does not change temperature while boiling. R134a is characterized by its efficiency in absorbing heat during phase change, while it’s low viscosity and a heat transfer coefficient of about 150 W/m²K making it effective for circulation in refrigeration systems. Also, R134a operate efficiently across a range of temperatures and pressures, making it easy to maintain and recharge.
Oil Compatibility
R407C
R-407C requires synthetic polyolester oils (POE), R407C is compatible with both new and existing installations of air conditioners, air handling units, heat pumps, refrigeration units, chillers, etc.
R134a
R134a requires Polyolester oils (POE), Polyalkylene Glycol (PAG) oils or Ester oils, alternatively, Polyvinyl ether (PVE) synthetic oils, polyalpha olefin (PAO) can be used.
Classification
R407C
R407C is classified by ASHRAE as A1/group L1; the R407C refrigerant gas is classified as a non-flammable and non-toxic refrigerant (except at high temperatures). R407C is a high-safety (A1) non-azeotropic and non-ozone-depleting hydrofluorocarbon (HFC) blend, R407C is widely used in the HVAC (Heating, Ventilation, and Air Conditioning) sector.
R134a
R134a is a hydrofluorocarbon blend (HFC), according to ASHRAE safety standards, R134a is classified as an A1 refrigerant (low toxicity and non-flammable).
Regulation
R407C
As per Montreal Protocol, R407C is used as a direct substitute for older R-22 HCFC fluid which was banned in 2015 in existing HVAC systems. Although R407C is increasingly used in the air conditioning and refrigeration systems (positive refrigeration), due to its high global warming potential (GWP) and because of its harmful effects in the atmosphere, R407C is subject to EU F-gas regulations, which restrict the usage of R407C in new equipment.
R134a
R134a has been the go-to choice for car air conditioning systems, even though R134a does not deplete the ozone layer, but due to its high global warming potential (GWP 1430) and its ozone-depleting properties, R134a replaced R12 which was banned under the Montreal Protocol, while R134a is gradually being replaced by natural refrigerants alternatives which have low-GWPs ranging from 0 to 6. R134a, hydrofluorocarbon (HFC) is regulated under EU F-gas regulations which aim to reduce harmful refrigerants and ensure low emissions of fluorinated greenhouse gases.
Global Warming Potential (GWP)
The global warming potential (GWP) is defined as a value that indicates the contribution to global warming, the GWP refers to the value of CO2 (GWP=1) as a benchmark, this means that a gas like R407C with its GWP of 1,774 contributes 1774 times more to global warming than the same amount of CO2, while R134A GWP of 1300 means that it contributes 1300 times more to global warming over a 100 year time span. However, the heating, ventilation, air conditioning, and refrigeration industry (HVAC&R) is moving toward natural refrigerants with low GWP 0 to 5.5.
R407C
R407C has a high global warming potential (GWP ≈ 1774), making it a significant contributor to greenhouse gas emissions and climate impact, R407C zeotropic refrigerant consists of mixtures of three HFC refrigerants (Difluoromethane R-32, Pentafluoroethane R-125, and 1,1,1,2-Tetrafluoroethane R-134a), made it not depleting to the ozone layer (ODP= 0). Although R407C contains no chlorine, but it has high global warming potential (GWP) value of 1700, which is higher than R134a.
R134a
R134A has relatively a GWP of 1430, which is lower than R407C refrigerant, even though R134a is a non-ozone depleting replacement for the CFC (Chlorofluorocarbon) R-12, but due to its high-GWP refrigerant, R134a is considered a greenhouse gas, this make it a significant contributor to the global warming issues. R134a is subject to regulatory restrictions, which restrict R134A use and replace it with climate-friendly alternatives such as R1234yf and R513A to reduce its high climate impact.
Can R407C and R134a be Replaced
R407C and R134a gases are both hydrofluorocarbons (HFCs) based blend, due to their high global warming potential (GWP), R407C possess a GWP of 1774, while R134a, has a GWP of 1430, R407C and R134a are regulated under the EU F-gas regulations which strictly sets the rules to reduce greenhouse gas emissions from fluorinated gases (F-gases) and therefore, combat climate change.
R407C Alternatives
R-407C refrigerant is developed as a replacement for R-22 gas in existing HVAC applications, industrial cooling and refrigeration systems, according to the Montreal Protocol, due to its cooling capacity and heating performance that is equivalent to R-22, Chlorodifluoromethane (R-22 or HCFC-22) is being phased out in 2020, because it contains chlorine which contributes to ozone depletion.
R134a Replacement
R134A has no Ozone Depletion Potential (ODP = 0), means that R134a does not harm the stratospheric ozone layer, since the mid-1990s, R134a refrigerant has been the go-to choice for automotive AC systems and car air conditioning systems, apart from that, R134a effective cooling performance making it the best replacement for R12 (Freon), which was banned due to its environmental impacts. Despite being effective and safe for the ozone layer, several natural refrigerants with low GWP ranging from 0 to 6, and low fluorinated greenhouse gas (GHG) emissions have emerged to replace R134a, including:
R1234yf
R1234yf, a hydrofluoroolefin (HFO) with an ultra-low GWP of 4, R1234yf provides a cooling performance comparable to R134a for vehicles’ AC systems and commercial refrigeration. R134a is a highly potent heat-trapping gas; due to its heat-trapping properties released into the atmosphere, R134a is considered a potent greenhouse gas. This makes natural refrigerants like CO2 (R744), hydrocarbons (like propane R290), and ammonia (R717) preferred for their sustainability. R1234yf is also known as 2,3,3,3-tetrafluoropropene, HFO-1234yf or by the chemical formula CH2=CFCF3.
CO₂ (R744, GWP = 1)
CO₂ (R744, GWP = 1) is a natural, non-toxic, and non-flammable gas used as a primary refrigerant, replacing high-GWP synthetic chemicals (HFCs or CFCs), thanks to its high operating pressures and excellent performance, which makes carbon dioxide (R744) ideal for complex and expensive components such as complex air conditioning, compact air-conditioning systems, modern cooling and heating, mobile air conditioning, commercial refrigeration, supermarket refrigeration, centralized cold-storage food chains, large industrial processing plants, industrial systems, industrial cold storage, heavy-duty compressors, low-temperature freezing, deep-freeze warehouses, domestic hot-water heating, medium-temperature cooling, vehicle cooling or heating, ships’ heating and air-conditioning, marine cooling systems, and CO₂ refrigeration systems (or heat pumps).
Hydrocarbons (R290, R600a)
Hydrocarbons (HCs) like R290 (propane) and R600a (isobutane) are highly efficient cooling gases, due to its excellent thermodynamic properties, Propane (R290, GWP = 3), and Isobutane (R600a, GWP = 3) has a very low global warming potential (GWP) of three, and an ozone depletion potential of zero. This made R290 (propane) preferred for medium-to-large cooling systems, while R600a (isobutane) is ideal for small systems like small refrigeration units, small home fridges, household refrigerators and AC systems. Both of the refrigerants (R290, R600a) comprise carbon and hydrogen. Despite being highly flammable, hydrocarbons (R290, R600a) can be handled according to safety regulations. Additionally, both of the propane (R290) and isobutane (R600a) are classified in safety class A3 because they catch fire very easily.
Ammonia (R717, GWP = 0)
Ammonia, designated as R717, is a natural gas made of an inorganic compound found in nature, making it safe for the planet. Ammonia (R717) is a non-ozone-depleting refrigerant (ODP = 0) with a global warming potential (GWP value of 0). Ammonia R717 is a single component consisting of a nitrogen and hydrogen mixture, making it one of the most efficient and cost-effective refrigerants used for large industrial refrigerators, industrial cooling processes, commercial freezer units, large cold storage facilities, food processing, and food storage. Ammonia is known for its superior thermodynamic performance, high thermal conductivity, heat transfer, and cooling properties, making it the most climate- and environmentally friendly refrigerant used for heating and cooling applications.
Conclusion
The planet is warming up and the climate is changing, R407C and R134A refrigerants are synthetic hydrofluorocarbon (HFC) cooling gases, R407C has a 100-year GWP of 1,774, making it a potent greenhouse gas that is slightly lower than R-22 gas which has a 100-year Global Warming Potential of 1,810, compared with R134a GWP 1,430, R407C GWP is still considered high. However, despite having lower atmospheric effects, climate impact is driven primarily by the increase of greenhouse gas (GHGs) due to carbon dioxide emissions, which contribute largely to global climate change while it makes the Earth’s temperature rising faster at an unprecedented rate.
You may also find this blog post useful:
What is a refrigerant? The ultimate guide.
Types of Refrigerants: The Complete Guide
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About The Author
Evan Wang
I am Evan Wang, the General Manager, Marketing Director, and SEO Expert at Sunnyda Cold Room. I have over 20 years of experience in the refrigeration industry, and my expertise is in commercial refrigeration solutions.
I’d be delighted to share practical ideas about refrigeration products, project selection, export trade, SEO, and marketing.
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