The refrigerant in a refrigeration system, regardless of type, is present in two different states. Refrigerants used in air conditioners are changing again. Always check the compressor manufactures recommendations for oil on any other type of cooling unit. The following links are to online readonly versions of these standards. The last round of changes took place between the mid1990s through 2010, as cfc and hcfc refrigerants were phased out and. Refrigerants physical properties engineering toolbox. Common refrigerants and environmental safety thermal systems.
Refrigerants and the refrigeration system determine the pressures. Swep is a worldleading supplier of brazed plate heat exchangers for hvac and industrial applications. During the refrigeration cycle, it changes from one state to the. Six types of refrigerant emissions, or losses, are identified. Originally the title given was new and alternative refrigerants but i was. If a refrigeration system is leak free, use of the existing. Pdf refrigeration and airconditioning play a vital role in domestic and industrial applications. The two refrigerant families most often used in air conditioning systems are hydrochlorofluorocarbons hcfcs and cfcs. Policylegislation on fgases and alternatives two environmental frameworks one goal the montreal protocol and the kyoto protocol.
It was banned in 1994 due to it harming the ozone layer. The danfoss product range for the refrigeration and air. Fellow ashrae mcquay international staunton, virginia usa 1 what is a refrigerant. Refrigerant types, issues, trends and future options. Figure 9 shows the different types of refrigerants. Designed to make the most efficient use of energy, material, and space, the technology is quickly. Refrigerants are divided into groups according to their chemical composition. The only way they will work is if you click the link within the ashrae website. Originally the title given was new and alternative refrigerants but i was also asked to. Special university course for future engineers lecture notes.
Standard thermometers of appropriate range are provided for the refrigerant system. Sydney games stated that cfc, hcfc and hfcfree refrigerants. The following is a list of refrigerants with their type prefix, ashrae designated numbers, iupac chemical name, molecular formula, cas registry number blend name, atmospheric lifetime in years. Originally the title given was new and alternative refrigerants. Manual for refrigeration servicing introduction technicians. Whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application. Thus, we have separate series for halogenated refrigerants and other types. Without being pressureregulated, primary refrigerants.
Class 1 refrigerants used in the standard compression type cooling system. New, natural and alternative refrigerants by dr s f pearson of star refrigeration limited introduction it is an honour to be invited to present this paper despite the rather daunting title. Prefixes should not be used for combined siunits except when kg is. Below is a list of the different oil types for the different refrigerants in our units. Since different fluids have the desired traits in different degree, choice is a. A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration. Understanding a2l refrigerants for air conditioners 2019. Primary refrigerants change states to absorb heat from surrounding areas or substances. Both types involve the use of refrigerant blends to achieve alternatives that will act very much like r502 in refrigeration systems. In the following section, different groups of refrigerants are discussed, some examples are given and their fields of application are described. From then on, reference to harmful gases from ac system will be clearly understood to imply the refrigerant in the. Each refrigerant type is denoted by a different series. Commercially, ammonia is made by combining free nitrogen and hydrogen gases under high pressure. There are many kinds of refrigerant and or refrigerant on the market today, but only a few that are widely used.
Present a comparison between different refrigerants section 26. Designation and safety classification of refrigerants. Volkmar hasse, gtz proklima, germany preface volkmar hasse, gtz proklima i. Here are some of the desirable properties of refrigerant. A refrigerant is a substance, usually a fluid chemical compounds, that is used in a. Refrigerants and their application presented by thomas e. The development of different refrigerants over time took place based on. The most common refrigerants for the first 100 years were familiar solvents and other volatile fluids. Pdf refrigerant types, issues, trends and future options. Properties of refrigerants n low boiling point and high latent heat of vaporization n dense vapor n low toxicity n non flammable n low miscibility with oil n low cost ammonia n has good heat transfer. Compare performance of multiple refrigerants, learn the line sizing, and much more all for free. Refrigerants capture heat and then release it to another space by using the thermodynamic phenomena of phase changes, in which a fluid changes to a gas or vice versa in the refrigeration cycle. Main types of compressors used in industrial refrigeration are screw, piston, centrifugal and rotary vane. Co 2 transcritical systems have also been driving the development of integrated heating and cooling systems, linking the refrigerant choice to the type of system.
Knowing the temperature difference across the coils, the amperage, and the airflow all give the technician vital information. During the last ten years, co 2 has become a viable refrigerant and can be used in different system setups. Refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed. Type of refrigerant and its availability if a system uses a chlorofluorocarbon cfc then it is likely to. Transcritical systems where co 2 is used in all circuits mt and lt. Class 2 refrigerants are used as direct cooling between the agents of class 1 and substances in the refrigerator. Properties of refrigerants michigan state university. The different types of refrigerants can be grouped as given below ashrae 2008. Another type, which is produced in large quantities, a scroll compressor, but still these compressors. The first type of blends incorporate the following refrigerants in two compositions to optimize different performance characteristics.
A refrigerant is a chemical that is used to provide cooling in a heat transfer system. The process is not easy, and although there are alternatives to old refrigerants, the new ones are usually not flawless. Co 2 transcritical systems have also been driving the development of integrated heating and cooling systems, linking the refrigerant choice to the type. A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration cycle.
Refrigeration and air conditioning multiple choice questions. Where a specific molecule can have different geometrical arrangements. The different types o f refrigerants can be groupe d as given below ashrae 2008. Standard 15 is the basis for the criteria on refrigeration safety in the. Natural refrigerants sustainable ozone and climatefriendly alternatives to hcfcs introduction dr. In most cycles it undergoes phase transitions from a liquid to a gas and back again. Simulate your system with the right refrigerant and export the results to excel. R12 was the refrigerant back in the 20th century for automobile applications. Refrigerants for commercial refrigeration applications.
Halocarbon refrigerants halocarbon refrigerant are all synthetically produced and were developed as the freon family of refrigerants. This type of magnetic refrigeration is said to produce refrigeration at. This section presents data for the thermodynamic and transport properties of refrigerants, arranged for the occasional users. New refrigerants impact standards and codes the function of refrigerant as a fluid used for heat transfer has not changed since the development of the first refrigerating system. Following the discovery that some of these chemical compounds may be harmful to the environment, they are being replaced with more environmentally friendly alternatives see figure 5. Its functions include drawing in the cool vaporized refrigerant that carries. Water has very different miscibilities with different refrigerants, and this fact has an important impact on the operation of refrigeration systems.
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