How does air conditioner refrigerant affect our environment? All of us have probably heard about the ozone layer which is located 35 miles above the ground. This upper layer of our earth's atmosphere protects the earth from the sun's ultraviolet rays by reflecting them back to space. UV rays are harmful to the plant, marine life and human beings on the earth.
How does air conditioner relate to the ozone layer? It was discovered in the mid 1980s that the commonly used air conditioner refrigerant has a damaging impact on the ozone layer.
At that time, the refrigerants that used then were known as CFC(chlorofluorocarbons) and HCFCs(hydrochlorofluorocarbons). CFCs are a family of chemicals that contain chlorine, fluorine and carbon. The chlorine content in these compounds cause the depletion of the ozone layer.
This discovery prompted the signing of Montreal Protocol of 1987, an agreement signed by 180 nations that target to phase out the production of CFCs by 1995 and HCFCs by 2030. As of January 2012, all the 197 countries in the world have ratified the Montreal Protocol.
New refrigerants that are being used to replace these CFCs are HFCs(hydrofluorocarbons) and refrigerant blends(Azeotropic, Zeotropic). In summary, the 4 commonly used refrigerants that you can find today are:
The future commonly used refrigerants will be in the last two categories. Among the currently widely used ones are R-134a, R407C and R410A.
The Montreal Protocol has undergone six Amendments:
The Kigali Amendment had agreed to reduce the use and production of HFCs as these refrigerants contribute to greenhouse effect causing global warming. HFCs use are projected to reduce by 85% by 2036 in developed countries and a reduction of 80% by 2045 in developing countries.
The latest country to ratify this amendment is Turkey on Nov 10, 2021. A total of 129 countries have ratified it as of this date. List of countries that have ratified it with the latest on top and date ratified.
Find out more about Montreal Protocol from UN Environment Programme.
More discovery on the causes of global warming had prompted many countries to sign the Kyoto Protocol in 1997. The main reason this was being done was to reduce the greenhouse effect caused by man-made greenhouse gas emissions.
Greenhouse gases include:
In the field of HVACR, refrigerant such as R32 has been widely publicized as a replacement for R-410A and R-407C as this gas has a lower Global Warming Potential. Lower GWP will reduce the greenhouse effect hence reducing the global warming effect. Many manufacturers are beginning to design and develop HVAC equipment using this refrigerant.
Do your part to preserve mother nature...
These refrigerants were developed more than 70 years ago and are harmful to our respiratory systems and the ozone layer. Their production was stopped since 1995 but are still being used widely in existing residential air conditioning units as many equipment have a lifetime of up to 30 years. Today's refrigerants used are from reclaimed units that are no longer in operation. The common ones still used are:
These air conditioner refrigerant is considered partially halogenated as they consists of methane or ethane in combination with chlorine and fluorine. They are shorter lifespan and are less destructive to the ozone layer compared to CFCs.
They are an interim solution to a totally "free from chlorine" refrigerant that are being developed. Their production are scheduled to be phased out totally in 2030. The common ones used are:
R-22 is used extensively in residential, commercial and industrial applications. The schedule of phaseout :
These air conditioner refrigerant contain no chlorine atom and is not destructive to the ozone layer though they have a slight effect on global warming. R-134a is used in new systems that are specially designed for its use. The common HFCs are:
The 1997 Kyoto Protocol puts R-134a as one of the 6 greenhouse gases that must be reduced. There is no phaseout date for this refrigerant and it is expected to be highly used in the HVAC industry.
These air conditioner refrigerant are also known as "azeotropic" and"zeotropic". Their use is increasing as they are environmental friendly. The setback is that the total air conditioning systems production cost is higher.
However, as more manufacturers switch to this type of refrigerants, the cost/unit will drop eventually. The common refrigerant blends used in the air conditioning industry are:
R-410A are used as a replacement refrigerant for residential air conditioning applications. R-407C are used as R-22 replacement.
Due to their higher GWP, R-410A and R-407C are being replaced by R32 refrigerant. Daikin, Mitsubishi Electric and many other manufacturers are designing new products that use this refrigerant.
The ASHRAE Standard 34 identifies the Hazard Classification of refrigerant based on flammability and toxicity of the refrigerant. For toxicity, the first character of the classification denotes the Class which is either A or B, Class A denotes refrigerants with lower toxicity and Class B with higher toxicity.
The subsequent one or two characters denotes its flammability. There are three classifications and one subclass. Class 1 is for refrigerants that do not propagate a flame when tested as per standard; Class 2 for lower flammability and Class 3 for highly flammable refrigerants. Class 2L is for refrigerant that burn very slowly.
Examples of A1 refrigerants are R-22, R-407C, R-410A, R-507A, R-513B and R-515B.
Examples of A2L refrigerants are R-32 and R-1234yf.
Example of A2 refrigerant is R-152A.
Example of A3 refrigerant is R-290.
Example of B1 refrigerant is R-123.
See the complete Ashrae Standard 34 that include a list of refrigerants with their safety group and global warming potential here.
Recovery, Recycling and Reclaiming of Refrigerants
Laws have been passed to prevent the release of CFC refrigerants into the atmosphere. The steps taken are:
The act of removing the refrigerant from a system and store it in an external container. No testing or processing is needed in any way.
Refrigerant is cleaned for reuse by oil separation and passes though devices such as core filter-driers. This procedure reduce the moisture, matter and acidity of the refrigerant for reuse. It is usually done for jobs on the field or service shops.
Reprocess the refrigerant to new product specifications which may include distillation process. This can only be done by manufacturing plants where chemical analysis is required. Highly equipped local service shops may have this facility as well.
How can consumer like you play your part in the effect to keep our earth green? You can do that by purchasing air conditioning systems that uses new refrigerant such as R-134a, R-407C, R-410A or R32.
Most equipment are labelled with stickers that indicate the type of refrigerant used. Examples are "ozone friendly" sticker or "R-410A" sticker.
If the HVACR equipment is available, choose lower Global Warming Potential refrigerant such as R32 to help reduce the greenhouse effect compared to if you were to use a higher GWP refrigerant.
Here are the top refrigerant manufacturers that you will probably encounter in the HVAC market.
This newer refrigerant is poised to replace R-22 and R-410A refrigerants as it has zero ODP and lower GWP.
Refrigerant Color Codes
See the color and color codes of the CFCs, HCFCs and HFCs refrigerants.
8 facts about refrigerant phaseout date
Facts you need to know about refrigerant phaseout date such as R-22 before making a decision with regards to purchasing or manufacturing air conditioner equipments.
Freon and the early history of refrigerants
Read a brief history of FREON and its impact on the environment.
Find out the properties and applications of R-134a ozone friendly refrigerant. This refrigerant has been designed to replace CFCs and HCFCs refrigerants.
Methods of refrigerants detection
Find out the various methods that are used to detect the refrigerant of a leaking system.