The four types of refrigeration systems you need to know. The following is a list of refrigerants with their type prefix, ashrae designated numbers. Synthetic and organic refrigerants are classified under two main categories, primary and secondary. It would not cause ozone depletion or climate change. Refrigerants are divided into groups according to their chemical composition. Most pre1994 model year vehicles used cfc12 also called r12. This should be as small as possible in order to have a small size of the compressor. Refrigerants a refrigerant is a substance used in a heat cycle. Manual for refrigeration servicing introduction technicians. Years ago, when chillers used cfcs and service practices were less concerned with minimizing emissions, leak rates. Kyoto protocol 1997 aims to curb all greenhouse gases. Type of refrigerant and its availability if a system uses a chlorofluorocarbon cfc then it is likely to.
The astm serves as a manufacturers reference document for minimum tightness. 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. Thermoelectric refrigeration systems are unique from the three other types of refrigeration in that no refrigerant or water is used. Many different refrigerants have been used in the past and are in use today with good ability to transfer heat from one place to another. In fact, from the thermodynamic or heatcarrying standpoint, differences among refrigerants with similar boiling points are small. Other common refrigerants used in various applications are ammonia, sulfur dioxide. For example, r600 is butane and r600a is isobutane. The ideal working fluid or often called refrigerant would have favorable thermodynamic properties, be noncorrosive to mechanical components, and be safe, including freedom from toxicity and flammability. The two main types of hazardous refrigerants used in vessel. Catalog oem3, distributors and flow controls page 3 refrigerant distributors refrigerant distributors are of two basic designs, each having certain merits that the design engineer may regard as best for the application. Chlorofluorocarbons are refrigerants that contain chlorine. There are many different types of refrigerant used in our industry today. Another type, which is produced in large quantities, a scroll compressor, but still these compressors are not available in the amount normally encountered in industrial refrigeration.
These naming conventions differ according to the type of refrigerant. The refrigeration systems vary according to the purpose and the type of refrigerant used. Characteristics of refrigerants pure r12 cc 1425f425 is colorless. Now its easy to access the pdf tools and files you need from anywhere. You should use the term refrigerant not the brand name when. Gwp of the refrigerant and the rate of refrigerant leakage into the environment. Chillers can be classified by compressor type, including.
Since different fluids have the desired traits in different degree, choice is a matter of tradeoffs. However, rather than providing a detailed reference list, each chapter is accompanied by a short list of. Pdf refrigerant types, issues, trends and future options. The selection of refrigerants in table 2 has been made in order to present the overview of cycle data for. R407a and r407c are examples of such refrigerants see section 5. In higher concentrations, its odor resembles that of carbon tetrachloride. Therefore, refrigerants must be acceptably safe for humans and manufacturing processes, with little or no toxicity or. Addendum c to ansiashrae standard 342001 3 a the molecular mass and normal boiling point are not part of this standard. Product information sorted by product type and name type product r number odp1 gwp2 cfc 12 1 high 10900 high 502 0,33 high 4657 high hcfc 22 0,055 medium 1810 medium 123 0,060 medium 77 low 401a 0,033 medium 1182 medium 401b 0,036 medium 1288 medium 402a 0,019. Whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application.
Automatic controls for industrial refrigeration systems. Hazards during the repair and maintenance of refrigeration systems on vessels the repair and maintenance of refrigeration systems can present hazards to both workers servicing these systems and those in the general area. First of all, there are 3 types of metering devices. They were developed in the 1930s and were used in a variety of industrial, commercial, household and automotive. Types of refrigerants chlorofluorocarbons cfcs these are refrigerants that contain chlorine, fluorine and carbon. A thermostatic expansion valve txv see figure 1 is a refrigeration and air conditioning throttling device that controls the amount of refrigerant liquid injected into a systems evaporatorbased on the evaporator outlet temperature and pressurecalled the superheat. Class 1 refrigerants used in the standard compression type cooling system. Common refrigerants and environmental safety thermal systems. Combine multiple documents and file types into one pdf file. 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 properties n not miscible with oil n but n toxic n flammable n corrosive to. The compressors are one of the most important parts of the refrigeration cycle. For others like r11 and water, a centrifugal compressor is required to.
One proper method of identification is referring to a refrigerant by its ansiashrae designation. Andrew, listing of refrigerants pdf, andys hvacr web page, archived from the original pdf on 20090319. The refrigerant used in mobile air conditioning systems. Designation and safety classification of refrigerants. A thermocouple is made up of two different metal wires that are united at both ends. Insulation separates the rest of the wires from each other. The heat gained by the refrigerant is rejected at the condenser and the high pressure refrigerant is expanded into the low pressure evaporator by the expansion valve. While leakage rates can vary widely among different hvac products, good design and servicing can keep leakage to a minimum. The process is not easy, and although there are alternatives to old refrigerants, the new ones are usually not flawless. The most common types of refrigerants in use nowadays are presented below. In ansiashrae standard 341997, the toxicity of refrigerants is classi. Working principle under this heading, we have the primary or common refrigerants and the secondary refrigerants. Standard thermometers of appropriate range are provided for the refrigerant system. Without being pressureregulated, primary refrigerants absorb all available heat.
The tables contained on this page list approved refrigerant numbers from ansiashrae 342019, designation and safety classification of refrigerants, the latest edition of standard 34, which describes a shorthand way of naming refrigerants and assigns safety classifications based on toxicity and flammability data. The delicate subject of refrigerants is widely discussed, viewpoints of different parties are opposite, depending on positions and interests, and compliance on that issue is not easy to achieve. The refrigerants have a thermodynamic property charge. Capital letters describe specific mixing proportions of different components. Ansiashrae addendum c to ansiashrae standard 342001. Water and brine solutions are common examples of secondary refrigerants. Special university course for future engineers lecture notes. Hazards during the repair and maintenance of refrigeration. Iir refrigerant cycle data 2, ashrae fundamentals handbook 3, or can be evaluated from suitable software such as refprop 4. They work on the principles of a bicycle pump and are characterized by a flow output that remains nearly constant over a range of discharge. It is odorless in concentrations of less than 20 percent by volume in air. Parker produces both basic types with the largest range of sizes, variations and specials of any manufacturer.
In todays world, other properties of the refrigerant are more important. The chance for closing the circle and return to natural refrigerants exists and should not be missed. These systems use an electric current and a thermocouple. This classification makes it possible to designate all refrigerants used in a clear and. In this study, performance of different refrigerants like r600a, r4a, r290, r1270, r32, r22, and r152a, in vapor compression refrigeration cycles and heat pumps was. What are the most common types of refrigerant today. Primary refrigerants change states to absorb heat from surrounding areas or substances. Classification can be divided into class 1, class 2, class 3. Present a comparison between different refrigerants section 26.
In the following section, different groups of refrigerants are discussed, some examples are given and their fields of application are described. This is a very general representation of the various units in a refrigeration system. They are produced by several different manufacturers and have numerous ways of identification. Refrigerant may leak from pipe joints, seals, or component parts during installation, operation, or accident. Product information sorted by product type and name. It is not the type of refrigerant used in most cars today. This section presents data for the thermodynamic and transport properties of refrigerants, arranged for the occasional users. A refrigerant is a chemical that is used to provide cooling in a heat transfer system.
Depending on whether they include chemical elements hydrogen h, carbon c, chlorine cl and florine f they are named after as follows. Its functions include drawing in the cool vaporized refrigerant that carries the heat energy from the evaporator coils, compressing it from a low pressure and tempera. There are many different types of oil that are used in the refrigeration cycle and it all depends mostly on two things. R410a is primarily used for home and commercial units made on or after 2010. Depending on whether they include chemical elements hydrogen h, carbon c, chlorine cl and florine f they. The extent of segregation depends on the particular azeotrope and hardware system configuration.
There are various types of compressors used in the refrigeration and air conditioning machines, these are. Approved by the ashrae standards committee on janu ary 29, 2003. In industry, reciprocating compressors are the most widely used type for both air and refrigerant compression. For example, r407 ae are mixtures of the refrigerants r32, r125 and r4a. Some automobile manufacturers have already switched over to the new hfo class of refrigerant known as 1234yf. Refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed.
These two compounds have the same chemical formula, but different spatial arrangements, and they therefore have slightly different properties. The compressor compresses the refrigerant, which flows to the condenser, where it gets cooled. Vehicle manufacturers have used two different refrigerants in automotive ac systems. The different types of cooling compressors a compressor acts as the heart of a refrigerant based mechanical cooling system. Refrigerants are classified according to their way of absorption or extraction of heat from substances stored in the refrigerator.
Chemical refrigerants are assigned an r number which is determined systematically according. The components in the mixture have different boiling points, and thus the refrigerant mixture has a temperature glide. The different types of refrigerants can be grouped as given below ashrae. The goal of a refrigerant lubricant is to lubricate the compressor and to also have the appropriate miscibility and solubility characteristics to interact with the refrigerant accordingly.
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