Since different fluids have the desired traits in different degree, choice is a matter of tradeoffs. Standard thermometers of appropriate range are provided for the refrigerant system. However, as a service technician you maycontinue to come across it for years to come. It is the fluid that flows continuously through the refrigeration cycle or vapor compression cycle absorbing heat from the low temperature reservoir and throwing it to the atmosphere or any other high temperature reservoir. Refrigerant tables and charts download ebook pdf, epub. Air conditioning and refrigeration industry refrigerant selection guide page 5 seventh edition january 2003 1. Apr 12, 2020 whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application. Properties of commonly used refrigerants a refrigerant is a substance or mixture. Although the perfect refrigerant with an ideal mix of environmental and physical properties has not yet been developed, some promising candidates exist. Because of the availability of isobutane all over the world it has been discussed widely for cfc replacement. Jun 02, 2019 properties of commonly used refrigerants a refrigerant is a substance or mixture.
In an industrial setting where more safety measures are in place and more refrigeration is needed, a class b and class 2 refrigerant. Aspects on the development of hfo and hfohfc refrigerants. Refrigerant is the life blood of the vapor compression cycle. Pdf refrigerant types, issues, trends and future options. Refrigeration n changes phase due to change in pressure n most common cryogens are n solid carbon dioxide n liquid carbon cook chill systems n used to replace warm holding of foods n cook chill system. Density density is fundamental physical property of oil. Most of the halogenated refrigerants meet these requirements. In higher concentrations, its odor resembles that of carbon tetrachloride.
A perfect refrigerant with ideal properties for every application does not exist. The decision to use the low gwp refrigerant r1234yf in mobile air conditioning systems for passenger cars low gwp hfo refrigerant r1234yf also led to the development of alternatives for further mobile applications as well as stationary refrigeration, air conditioning and heat pump systems. Usually, a fluid, used in a heat pump and refrigeration cycle that can extract heat from another body or substance. They also have good energy efficiency, but are flammable and can form an. While leakage rates can vary widely among different hvac products, good design and servicing can keep leakage to a minimum. Physical properties of refrigerants molecular weight, boiling, freezing and critical points.
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 copper pipes carbon dioxide n non toxic n non flammable n but n higher. A comparison between refrigerants used in air conditioning. These refrigerants are primarily used for air conditioning and heat pumps and have replaced r22 in many applications. Compare performance of multiple refrigerants, learn the line sizing, and much more all for free. Hfc125 hfc143a hfc4a freon 404a r404a, wt% 44 52 4 the individual components of the three mixtures are listed in table 1 to show their chemical names and formulae. R4a is capable to be at temperatures of 28c at room temperatures of 38c, its performance being very similar to that of an r12. Jul 17, 2017 a good refrigerant has the right combination of safety and functionality. For example, in a regular home refrigerator, a class a and class 1 substance are used.
A throttling valve should be used to control the flow of refrigerant to the suction side to ensure that a liquid. This paper explores the ongoing efforts by those who are anticipating the more widespread use of flammable refrigerants in hvac equipment and appliances, with the principle focus on. Please note that for reduced gwp, klea 407a offers a good alternative. This refrigerant is called freon 404a r404a, and its composition is. R407c refrigerant has been formulated as a good match to the existing hcfc refrigerant r22 for use in air conditioning, chilling and refrigeration applications and was the first of the r22 alternatives to be used on a commercial scale. Airah wishes to acknowledge the assistance provided by. The bubble pressure is used for determining the system pressure when the refrigerant is in a saturated liquid or subcooled condition i. Note that in most cases, equipment designed for r22 cannot use r410a because of this difference in operating pressures, so retrofitting an existing r22. In the present study, recent research is considered about new generation refrigerant r1234yf and r1234ze e.
The toxicity depends upon the concentration and exposure limits. Table 1, on pages 4 and 5, shows the properties of r22 at satur ation. It has been used in refrigeration systems since 1840 and in vapor compression since 1860. The general conclusion of the thesis is that the refrigerant affects all of the measured properties negatively on the subject of lubrication and life of the rolling element bearing. Design changes to the condenser and evaporator need to be done to use this refrigerant. In some applications it may be necessary to consider other properties of the refrigerant, such as its interaction with the process fluid in the event of a pinhole leak. Thus the normal boiling point is a good indicator of the critical temperature of the refrigerant.
Following are properties of a good refrigerant given below. R22 will soon be phased out, so you will not see it as much as you do other refrigerants in the future. In terms of its properties, it should be considered a highclass refrigerant. In the last two centuries, human ingenuity made it possible to control fully. Whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application. It is odorless in concentrations of less than 20 percent by volume in air.
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. It would not cause ozone depletion or climate change. Technical information at22 thermodynamic properties of dupontz freon. The saturated and boiling steam properties of refrigerants r22, r4a, r32, r152a, r290, r1270 and r600a to be analyzed have been taken from the.
Characteristics of refrigerants pure r12 cc 1425f425 is colorless. Solstice n40 r448a refrigerant honeywell refrigerants. Desirable properties and commonly used refrigerants. Of flammable refrigerant in room airconditioners used for human comfort flammability group of the refrigerant occupancy classification location classification of rac equipment 15 for example, r32 group 2l and r290 group 3 have different flammability properties which affect. This site is like a library, use search box in the widget to get ebook that you want. Ammonia, r717, is an attractive refrigerant alternative.
This paper contains a summarized look at our experience and knowledge, describing the background, trends, and drivers that frame the scenarios for present and future refrigerant selection. Refrigerants are widely used in refrigeration cycle where cooling effect below the. R404a refrigerant is an established alternative to r22 and r502. Part of this chapter deals with a refrigerant r22 that will soon be phased out of production. This section presents data for the thermodynamic and transport properties of refrigerants, arranged for the occasional users. These properties can be divided into favourable thermodynamic, chemical and physical properties. Properties of a good refrigerants mechanical engineering.
R4a has relatively low pressure and therefore about 50% larger compressor displacement is required when compared to r22. It is measured at specific temperature by hydrometer or automatic density meter. For refrigerants this means certain chemicals will be phased out and others restricted. The refrigerant is a heat carrying medium which during their cycles i.
Physical properties of refrigerants low freezing point. Comparison of environmental impacts and physical properties of refrigerants ko matsunaga executive summary even before the invention of refrigeration, people wanted to improve their life by using ice to provide cold drinks and preserve food. Refrigerants have been a key component of air conditioning and refrigeration systems since the 19th century. Gwp of the refrigerant and the rate of refrigerant leakage into the environment. Refrigerants and their application presented by thomas e. Third, ammonia refrigeration has a proven safety record, in part because of the refrigerant s physical properties not the least of which is its. Review of the thermophysical properties and performance. This is a haloalkane refrigerant with thermodynamic properties similar to r12 dichlorodifluoromethane but with insignificant ozone depletion. Key properties of the main refrigerants are given in together with their typical application ranges. However, the compressor must use a synthetic polyester lubricating oil. The important properties such as latent heat of vaporization and.
Thermodynamic properties of refrigerant r4a, also known as 1,1,1,2tetrafluoroethane, r4a, freon 4a, forane 4a, genetron 4a, florasol 4a, suva 4a or hfc4a and norflurane inn. Oct 25, 2018 refrigerant trends in thailand have shown improvements in increasing energy efficiency and decreasing globalwarming potential gwp, as shown in figure 3 7,8, which is related to the figure 2. Fundamentals of mechanical refrigeration systems course content introduction mechanical refrigeration is a thermodynamic process of removing heat from a lower temperature heat source or substance and transferring it to a higher temperature heat sink. The choice of refrigerant is becoming more complex and this chapter can only be considered as an introduction. Oct, 2015 a lubricant is a substance introduced to reduce friction between surfaces in mutual contact, which reduces the heat generated. Refrigerant options now and in the future white paper. Some fluids, however, are better than others, as evidenced by the bans placed on ozonedepleting refrigerants.
Update on next generation low gwp refrigerants for. In fact, from the thermodynamic or heatcarrying standpoint, differences among refrigerants with similar boiling points are small. Thermophysical properties of refrigerants t his chapter presents data for thermodynamic and transport properties of refrigerants, arra nged for the occasional user. Here are some of the desirable properties of refrigerant explained in detail. This refrigerant is not 100% compatible with the lubricants and mineralbased refrigerant currently used in r12. A summary of general and environmental properties of refrigerants is given in the icheme guide and more detailed information in the ashrae handbooks. The following is a list of refrigerants with their typeprefix, ashrae designated numbers. Isobutane r 600a is a possible refrigerant for this application, with good energy efficiency.
Refrigerants r402a, r402b, and r404a properties, uses. Refrigerant selection designing buildings wiki share your construction industry knowledge. Fortunately ammonia has been very thoroughly studied by thermodynamicists over the years and. Usually, a fluid, used in a heat pump and refrigeration cycle that. The earth is surrounded by a thin film of gases which form the atmosphere. To enable the use of smaller compressors and other equipment the refrigerant should have smaller vapor. Refrigerant these properties are practically not found in any refrigerant. The desired thermodynamic properties are a boiling point somewhat below the.
The good properties of a refrigerant are as follows. Effects of refrigerant properties on refrigerant performance citeseerx. The hydrocarbons like r600a, r290 and r1270 are good alternatives to r12. This new refrigerant worked very similar to r4a but had a gwp of only four. The refrigerant in any refrigerator or air conditioner flows continuously through the vapor compression cycle, absorbing the heat in the evaporator and releasing it in the condenser. Everything you need to know about the coming changes in the global, federal, and state refrigerant landscape karim amrane, ph. In todays world, other properties of the refrigerant are more important. Years ago, when chillers used cfcs and service practices were less concerned with minimizing emissions, leak rates. Steve is a distinguish service member of ashrae and is involved in numerous refrigerant safety standard 34 and use standards used globally by the hvacr. Jul 12, 2019 a perfect refrigerant with ideal properties for every application does not exist.
In an industrial setting where more safety measures are in place and more refrigeration is needed, a class b and class 2 refrigerant are generally used. In addition, the physical properties of the freon hp refrigerants are listed in table. Chlorofluorocarbons cfcs had been phased out under the montreal protocol. These physical properties of refrigerants help us select the proper refrigerant for the application as per our requirement. Refrigerants physical properties engineering toolbox. A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration. Aside from technological advances, a major change to their use is the increasing focus on reducing the impact on the environment.
Appendix a thermodynamic property tables general because of ammonias widespread use as a refrigerant, comprehensive tables of thermodynamic properties are frequently needed by refrigeration engineers. A good refrigerant has the right combination of safety and functionality. Be preparedremember that good troubleshooting requires a thorough understanding of the basics. Everything you need to know about the coming changes in. The refrigerants have a thermodynamic property charge. High critical temperature to have large isothermal energy transfer. Visual ratings were obtained on both the liquid solutions and. In the last two centuries, human ingenuity made it.
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. Physical properties of refrigerants molecular weight, boiling, freezing and critical points engineering toolbox resources, tools and basic information for engineering and design of technical applications. With r410a, the same unit will operate under the same conditions with a suction pressure of 118 psi and a discharge pressure of 400 psi, as shown in figure 1 on the next page. Carbon dioxide is widely used as a refrigerant in mechanical systems refrigerant, marine services, hospitals, etc. Physical properties of lubricants valvolinecummins.
Simulate your system with the right refrigerant and export the results to excel. Click download or read online button to get refrigerant tables and charts book now. Suitable for retrofit and original equipment usage. The specific heat of liquid should be as small as possible and of vapour should be as high as possible to give less superheating of vapour. Today, as in that first system, the refrigerant absorbs heat and transfers it at a higher temperature and a higher pressure, usually with a phase change. It is essential that systems be charged with liquid from the cylinder. Engineering toolbox resources, tools and basic information for engineering and design of technical applications. Toxicity is the important properties of refrigerants. In some applications it may be necessary to consider other properties of the refrigerant, such as its interaction with. Safety is perhaps the most important single factor in the selection of a refrigerant. 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 objective of this thesis is to increase the understanding of lubricating rolling element bearings in refrigeration compressors. At first the push to phase out 4a was stalled as there wasnt a good substitute out there.
If possible, the refrigerant must be odorless, but easy detection in the air is desirable. The use of smaller hoses and 30% increase in control pressure regulations also have to be done to the system. The refrigerants should be non poisonous to humans and food stuff. Both the neat lubricant and a mixture of lubricant and refrigerant 5050 volume ratio were tested. This article describes thermodynamic properties of the refrigerants the ideal refrigerant. Key properties of the main refrigerants are given in table 3. Table 1, on pages 4 and 5, shows the properties of. It is odorless, nontoxic, nonflammable, nonexplosive and noncorrosive. After some time the two main refrigerant innovators honeywell and chemours came out with a new refrigerant under their hfo line known as r1234yf. Feb 14, 2017 following are properties of a good refrigerant given below. Sustainability safeguards longterm investments and ensures compliance with.
If possi ble, the refrigerant must be odorless, but easy detection in the air is desirable. The refrigerants have a thermodynamic property chart on pressureenthalpy coordinates with an abbreviated set of tabular data for saturated liquid and vapor on the faci ng page. High latent heat of vaporization to get more refrigeration effect. So, a tradeoff has to be done in order to achieve as high a cop as possible. Physical properties of lubricants valvoline technical services page 1 following are the important properties of a lubricant. Vapour charging solstice n40 may result in the wrong refrigerant composition and could damage the system. The production and use of cfcs is restricted by the montreal protocols. Fellow ashrae mcquay international staunton, virginia usa 1 what is a refrigerant. Agas au11734 r22 is a single component hcfc refrigerant that has historically been used for air conditioning, medium temperature and low temperature refrigeration. Refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed. New refrigerants to replace cfcs comprise an active area of development. Thermodynamic properties of duponttm freonr 22 refrigerant.
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