The refrigerants have a thermodynamic property charge. Specifications of embraco refrigeration compressors. Mar 26, 2020 nomenclature of refrigerants or designation of a refrigerant refrigeration and air conditioning mechanical engineering notes edurev is made by best teachers of mechanical engineering. Refrigerants are classified by ashrae, and their friends r numbers are assigned in accordance with certain rules. If the eighth character in the model nomenclature is the letter e then the. The new class of hfo refrigerants are based on the propylene propene molecule r1270, ch 3 ch ch 2. This document is highly rated by mechanical engineering students and has been viewed 38 times.
For example, classification of refrigerants derivatives of hydrocarbons, saturated and consisting of one substance only shown in the example below. This checklist has been prepared by sspc 34 to assist applicant preparation of a new refrigerant application in accordance with the requirements of ansiashrae standard 3420, designation and safety classification of refrigerants. Refrigerants are classified by ashrae, and their familiar r numbers are assigned according to certain rules. These are the mixtures of two or more refrigerants and behave as a compound. Oxygen and nitrogen compounds refrigerants having either oxygen or nitrogen molecules in their structure, such as ammonia, are grouped separately and have a separate nomenclature from the halogenated refrigerants. Dec 06, 2017 shortcuts to remember designation and their chemical formula for organic refrigerants, refrigerants are r11, r12, r22, r1, r114, r4. Hcfc and hfo nomenclature basic principles cfcs, hcfcs, hfcs, hcs and pfcs in the identification of fluorocarbons, use is made of prefixes and sets of numbers andor letters. Discuss the importance of selection of suitable refrigerant in a refrigeration system section 26. Fellow ashrae mcquay international staunton, virginia usa 1 what is a refrigerant. Chemical refrigerants are assigned an r number which is determined systematically according to molecular structure. The model nomenclature denotes if the compressor is charged with a poe lubricant. For example, the classification of halogen refrigerants derived from saturated hydrocarbons and consisting of only one substance is illustrated in fig. Some of the refrigerants in group b are described in more detail below. Desirable properties and commonly used refrigerants.
A comparison between refrigerants used in air conditioning derya ozkan, ozden agra and ozlem cetin university of yildiz technical university, turkey corresponding email. 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 designation rxyz is determined by the chemical composition of the molecule, as described below. Chemical refrigerants are assigned an r number which is determined systematically according. Seminar is focused on the fundamentals of vapor compression refrigeration system which is principally applicable for all automotive, domestic and industrial airconditioning and refrigeration applications. Various ways of substituting the atom or group on the carbons can exist and this is denoted by two lowercase letters see figure 3. Prefixes typically consist of the letters h, c, f and c, whereby h stands for hydrogen, the first c for. Working fluids in refrigeration cycles undergoes phase transition in cycles mostly before going to subject topic first of all we divide all refrigerants in following categories. The tables contained on this page list approved refrigerant numbers from standard 34, which describes a shorthand way of naming refrigerants and assigns. Oct 04, 2016 hey guys, refrigerants is nothing but. Jan 17, 2017 now that you know a little more about the history and general types of refrigerants i recommend you read part 1 if you havent already its time to get to the really interesting part, refrigerant nomenclature or naming convention.
Designation and nomenclature information june 27th, 2016 disclaimer. Jan 10, 2017 therefore, i present our first two part series, refrigerant history and nomenclature. According to an international agreement, refrigerants are represented by the letter r as in refrigerants followed by a two or threedigit number and, in some cases, one or two letters. Refrigerant history and nomenclature part 2 forward engineers. Usually, a fluid, used in a heat pump and refrigeration cycle that can extract heat from another body or substance. It does not present official positions of the society nor reflect society policy. Environmental safety issues have led to calls for the careful investigation of currently used refrigerants hfcs and potentially applicable hc refrigerants r290.
Class 1 refrigerants used in the standard compression type cooling system. With increasing regulatory and legislative actions to limit production, use, or emission of specified. The following is a list of refrigerants with their typeprefix, ashrae designated numbers, iupac chemical name, molecular formula, cas registry number blend name, atmospheric lifetime in years, semiempirical ozone depletion potential, net global warming potential over a 100year time horizon, occupational exposure limitpermissible exposure. A refrigerant is a substance, usually a fluid chemical compounds, that is used in a refrigeration cycle to cool a space. This refrigerant was introduced commercially in the early 1960s for low temperature applications and is particularly suitable for hermetic compressors. Hfchfo refrigerants require the use of a poe lubricant to provide proper miscibility and lubricity. R502 together with hcfc r22 became the definitive refrigerants. Nextgen minicons are ideally suited for use in a variety of commercial applications such as cafeterias, convenience. Jun 02, 2019 a refrigerant is a substance or mixture. The following is a list of refrigerants with their typeprefix, ashrae designated numbers, iupac chemical name, molecular formula, cas registry number blend name, atmospheric lifetime in years, semiempirical ozone depletion potential, net global warming potential over a 100year time horizon, occupational exposure limitpe. 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. Refrigerant types, issues, trends and future options. The process is not easy, and although there are alternatives to old refrigerants. Zeotropic mixtures are given an identification number in the 400 series.
Until recently, refrigerants were referred to by standardized designations or trade names. By steve kujak, member ashrae flammability and new refrigerant ptions increasing concerns about the impact of refrigerants on the environment and on. A comparison between refrigerants used in air conditioning. Full details of the nomenclature system are specified in ansiashrae standard 341992 with additional annual supplements. Application guidelines copeland scroll compressors for air. Call your local branch for availability removing the mystery from model numbers tecumsehs compressor and condensing unit model numbering system is a combination of significant numbers and letters, which condense a great deal of information into a small space. Addendum c to ansiashrae standard 342001 3 a the molecular mass and normal boiling point are not part of this standard. Refrigerants are classified according to their way of absorption or extraction of heat from substances stored in the refrigerator. Pdf seminar is focused on the fundamentals of vapor compression refrigeration system which is principally applicable for all automotive, domestic and. Mseries medium temp condensing units with hermetic.
The engineering nomenclature of refrigerants, as defined by ashrae socalled r names, and iupac nomenclature are compared. Refrigerants and their application presented by thomas e. Many accounts will trace refrigerants all the way back to the mid1700s when scientists were doing early experiments with evaporation and noticing that the temperature would drop significantly. The generally preferred oil for use with hfcs is a polyol ester poe that has an additive package for refrigeration applications. Pdf refrigerant types, issues, trends and future options. As the slurried polyethylene is removed, isobutane is flashed off, and condensed, and recycled back into the loop reactor for this purpose. The tables contained on this page list approved refrigerant numbers from standard 34, which describes a shorthand way of naming refrigerants and assigns safety classifications based on toxicity and flammability data. Refrigerants having either oxygen or nitrogen molecules in their structure, such as ammonia, are grouped separately and have a separate nomenclature from the halogenated refrigerants. Common refrigerants are frequently referred to as freon.
While such nomenclature is intended to distinguish specific attributes, nonuniform usage may. It is used as a replacement for r11 a group a refrigerant that is a cfc. Chemical names are frequently used in place of the numbers for common materials such as trichloroethylene and chloroform. Some remarks on the nomenclature of refrigerants sciencedirect. To enable the use of smaller compressors and other equipment the refrigerant should have smaller vapor density. Group b refrigerants are toxic, so users of these need to be more cautious. Classify refrigerants into primary and secondary, and. Classification can be divided into class 1, class 2, class 3. Nomenclature of refrigerants or designation of a refrigerant. Nomenclature of organic refrigerant is very easy to. Refrigerants nomenclature is discussed along with a simple question based on ese pattern. The components in the mixture have different boiling points, and thus the refrigerant mixture. Tricks to remember designation and their chemical formula for.
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