1、COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesSTD-ASHRAE JOURN 37-12 FDA-ENGL 1997 M 0759b50 0532070 45T COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesSTDSASHRAE JOURN 37-1
2、2 FDA-ENGL 1777 I0757b50 0532073 37b December 1997 I ASHRAE Journal 1 (Circle No. 4 on Reader Service Card) COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesI ust think, a single control system thats smart enough to deliver a simple, J sea
3、mless connection for all commercial building and industrial process controls. Now, think Siebe. Introducing Intelligent Automation . the revolutionary system thats built on BACnet“ and lonMark. Today, theres one system that can handle all your I building control needs. With unlimited scalability and
4、 interoperability. And an COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesJ omszon. Next to freeze-ups, its one of the biggest t
5、hreats to heating and cooling efficiency water-based HVAC systems face. Even under relatively moderate conditions, corrosion can rapidly strip away precious layers of metal from system components and eventually foul chiller coils. As the photos above illustrate, an uninhibited glycol- based fluid ca
6、n cause corrosion. Yet, even an inhibited glycol fluid will corrode your system if its not inhibited properly. Comparative Corrosion Effects of Fluids on Common Metals Corrosion Rate (mils per year) Uninhibited Uninhibited Propylene DOWFROST Ethylene DOWTHERM Water Glycol HD Fluid Glycol SR-1 Fluid
7、Copper 0.08, 0.16 0.04 0.16 0.12 Brass 0.23 0.20 0.08 0.46 0.12 Solder 3.14 -34.7 0.06 56.5 0.13 Mild Steel 9.69 9.80 0.04 44.5 0.04 Cast Iron 21 2 16.2 0.05 55.7 0.13 Aluminum 13.2 1.80 +0.36 19.8 0.44 Ra.tes in excess of 0.5 mpy (2.5 for aluminum) are generally evidence of inadequate corrosion pro
8、tection. Sample with a “+“showed weightgain. ASTM D1384-19O”F for 2 weeks, 30% by volume glycol, air huhbling. DOWTHERM- and DOfJ(IFROST* fluids, on the other hand, contain precisely formulated industrial inhibitor packages that are proven highly effective in preventing corrosion of metals commonly
9、used in HVAC systems. And, unlike some other inhibited glycol fluids, DOWTHERhl and DOWFROST fluids can be easily analyzed to determine corrosion inhibitor condition. Properly maintained, DOWTHERM. and DOWFROST fluids may not require reinhibiting for up to 20 years. Another reason DOWTHERM and DOWFR
10、OST fluids are such a good bet for HVAC systems? Theyre backed by complete fluid support services, including free annual fluid analysis for systems containing 250 gallons of fluid or more. I For our 12-page HVAC applica- tions guide and a deck of limited edition playing cards, absolutely free, call
11、1-800-447-4369 or use the reader service card. DOWINERM and DOWROST. Heat Transfer Fluids http:/lspeciaIty/heat/heat. html (Circle NO. 19 on Reader Service Card) Trademark of The Dow Chemical Company 4 ASHRAE Journal December 1997 COPYRIGHT American Society of Heating, Refrigerating and AC Engineers
12、Licensed by Information Handling ServicesColder Temperatures in Display Cases: Meeting 1993 FDA Code Increases Energy Use and Refrigeration Load By Ramin Faramarzi, P.E. and Michele Wood Less than One Watt per Square Foot Dual, Dissimilar Boiler Flame Safety C Operating and Maintaining Rooftop A Pas
13、sive Solar-Heated Courthouse 35 Space Cooling Demands from Office Plug Loads: . 41 45 50 By Paul Komor, Ph.D By Peter F. Hoex P. E. By David Houghfon, P.E. . By James Coupland, P.E. . Trends and Issues ASHRAE Winter Meeting Preview . ASHRAE Technical Program . Editorial (Author/Subiect) Index for 1
14、997 Commentary . Industry News . Washington Report Forum Meetings and Shows Standards . . 34 Focus on Valves and Pumps Products . 158 Classified Advertising Advertising Index Reader Service Card . nt r In 7 993 the FDA recommended a lowered shipping, receiving, and storage temperature for potentiall
15、y hazardous food (meat, dairy, deli, fish, poultry, and cut produce) to aid in preventing food-borne diseases. On Page 35, Ramin Faramarzi discusses a prolecf that tested and evaluated fhe impacf of the 7 993 FDA code on power use and performance of a multi-deck display case used for storing dairy p
16、roducts. DECEMBER 1997 VOLUME 39 NUMBER 12 COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesFred Turner Editor ASHRAEs Contributi
17、on he 1992 ASHRAE position paper on ozone-depleting substances says that T ASHRAE can make its greatest contribution in this area through technology transfer and education. The recent ASHRAE/TuIST Conference: Refrigcrants for the 21 st Century in Bethesda, Md. contributed in both ways. The 16 papers
18、 focused on equipment and refrigerant options involved in the search for replacements for chlorofluorocarbons (CFCs) and hydrochlorofluorocar- bons (HCFCs). Most papers covered recent research and the prospects that each option has for satisfying requirements that include safety, stability, cost, ef
19、f-ciency, and ozone depletion and global warming potential. Topics ranged from heat pump and absorption technology, to refrigerant options such as ammonia, fluoroethcrs, carbon dioxide, propane and even air. Several articles on the conference are included in this months Industry News section. The co
20、nference proceedings are available through ASHRAE. REFRIGERANT technology also will be covered in the ASHRAE Winter Meeting Technical Program in San Francisco. The program will be the Societys largest for a winter meeting with 192 papers presented in 3 1 symposia, three techni- cal sessions and thre
21、e poster sessions. The program also has 43 seminars and SO forums. The program is presented in 15 tracks, or subject areas. The largest track is Systems and Applications, followed by IAQ and Comfort. The third largest track is Materials and Processes, which includes programs on refrigeration equipme
22、nt and refrigerants. A seven-page preview- of the Winter Meeting, the Technical Program and the AHR Expo starts on Page 139. Incidentally, Hank Stevens, the shows manager, says that San Francisco has many more downtown hotel rooms than Philadelphia. AN ARTICLE in this months lineup questions a basic
23、 assumption regarding plug loads, which account for 15% to 20% of an offices cooling load. Most design- ers assume 2 to 5 watts per square foot (21.5 to 53.8 W/m2) for office equipment. Author Paul Komor, Ph.D., presents data from 44 office buildings that shows plug loads are actually 1.1 watts per
24、square foot (1 1 W/m2). In other articles, Ramin Faramarzi, P.E., and Co-author Michele Woodworth present the results of a study on the impact of federal guidelines for temperatures in dairy display cases; Peter Hoey, P.E., describes a project to upgrade the boiler flame safeguard system for a state
25、 housing authority; David Houghton, P.E., presents a primer on maintaining rooftop air conditioners; and James Coupland, P.E., describes his award-winning design of a passive solar-heated courthouse. WE HOPE you keep all ASHRAE Journals for future reference. The December issue is helpful because it
26、includes an index of the 1997 ASHME Journal authors. The articles also are indexed by subject. The indices start on Page 149. December 1997 COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesNew Approach to IAQ Urged Speakers at IAQ 97 Say R
27、afe of Illness Dehonstrates Need BETI IESDA, Md.-Increased rates of respirator) illnesses in people at work, school and home demonstrate a need to improve the quality of indoor air, espe- cially through an interdisciplinary ap- proach involving engineers, medical professionals, building owners and o
28、c- cupants, concluded participants at the Healthy BuildingsiIAQ 97 conference here Sept. 30-Oct. 2. The conference, Co-organized by ASHRAE, the Virginia Polytechnic In- stitute and State University and the In- Jonathan Sammet ternational Society of Indoor Air Qualitj and Climate, featured serveral r
29、eports announcing increases in the inci- dence of Iicalth problems and recom- mendations for intervention from health and building scientists and practitioners. In the United States and Australia, asthma rates have nearly doubled in the past 15 ycars, reported Dr. Rebecca Bas- coni of the University
30、 of Maryland, with an annual health care cost in the Ilnitcd States of more than $6.2 billion, accord- ing to the American Lung Association. Bascom also reported that teachers are at a greatly increased risk of respiratory and other serious health consequences of long deferred maintenance in aging s
31、chool buildings. And, in young people, once thcy become sensitized to a disease, it be- comes a lifetime health event, shc said. Dr. Ed Nardell of Harvard University warned that as inany as 30 million tuber- culosis (TB) deaths inay occur over the next decade, a high percentage of which will be attr
32、ibutable to transinission of IB in poorly ventilated spaces. TR is the worlds most common buildiiig-related disease. Nardell noted that a mortality rate of 50% is expected among patients and health care workers who are infected with HIV and drug-rcsistant TB. From a medical perspective, the ge- neti
33、cs of peoples susceptibility to dis- ease has reinained the same. What has changed, however, is the number of trig- gers that can bring on disease in people, said Dr. Jonathan Sainmet of Johns Hop- kins University. The sources of indoor air pollution are many, such as environmen- tal tobacco smoke,
34、volatile organic coni- pounds in inaterials in buildings, allergens and molds. However, Sainmct reported there are many opportunities for intervention to control indoor air pollu- tion, such as use of low-emitting niateri- als, eliminating smoking indoors, control of moisture and dirt in IIVAC syste
35、m, and proper maintenance and operation of HVAC systems. The conference emphasized the need for medical and building professionals to work together for the occupants benefit, said James E. Woods, Ph.D., Fellow ASHRAD, Co-chair of the conference. Medical professionals could more accu- rately and quic
36、kly determine symptoms See IAQ Conference, Page 9 December 1997 8 ASHRAE Journal COPYRIGHT American Society of Heating, Refrigerating and AC EngineersLicensed by Information Handling ServicesFrom a medical perspective, the genetics of peoples suscep- tility to disease has remained the same. What has
37、 changed is the number of triggers that can bring on disease in people. Dr. Jonathan Sammet IAQ Conference, From Page 8 tems on the occupants health. In addition to operation and mainte- and causes of health effects, such as the nance, the measurement of ventilation ef- use of air-cleaning devices t
38、hat produce fectiveness can determine how oLone and could contribute to long-term efficiently air is being mixed and deliv- lov-level exposures. Building pi als could benefit by under- standing Lvliat conditions will contribute to the accumulation of indoor air pollutants by the design of certain sl
39、stems or through the operation and maintenance of the HVAC equipment and systems, he said. John Spengler of Harvard Univcrsity reported that changes to a buildings de- sign during construction of- ten contributes to indoor air rofession- ered to John Spengler pollution. In the process of constructin
40、g a building, changes are made at the con- struction site that affect the design ofthe HVAC system and produce unrecog- nized problems which later have impli- cations on the quality of indoor air. During the operation of building HVAC systems, control ofmoisture, dirt and ventilation is important to
41、 prevent indoor air pollution, said Woods. Con- trolling moisture and dirt eliminates the growth of microbials in HVAC systems and in the building. Once you control the source of indoor air pollut- ants, ventilation is used to di- lute the concentration of remaining pollutants with outdoor air and r
42、ecirculated indoor air, he said. Woods recommended three important roles fr building professionals to assure the quality of indoor air: I) to use ventilation to control airborne transmission of biological idoor air spaces. At the confer- ence, a new model that predicts the movement and “age” of air
43、for multizone sys- tems was presented by Clif- ford Federspiel of Johnson Controls, Inc. Ventilation control is often described in terms of airflow rates while ventilation pcrfor- mance is described in tenns of the age of air. The model inte- grates thcsc two concepts through a ventilation control s
44、trategy that ineasures the age of the air in locations throughout a building. The age is determined from when it cnlcrs the outdoor intake to the moment that it is being measured, he said. The model, de- veloped in response to a need to accurately measure ventilation rates to verify that they meet A
45、iVSJASHRAE Stuiidud 62-1 989, Venrikuiioii foi. Acceptable Indoor. Air. Quuliv, also includes calculations for three different ways to measure air change effectiveness. By examining the results, it can be determined how air is moving in a room. “Results from the model can also be used to determine h
46、ow to redistribute air within in- door spaces to improve effec- tiveness. Redistribution of air can significantly reduce the required amount of outdoor air for ventilation, in some cases by 30%,” said Feder- spiel. Also new data presented shows that greater thermal v agents, 2) to create greater Llf
47、ford Federspiel com fort and lower energy “accountability” among pro- costs can be achieved by low- fessionals involved in the design, con- ering relative humidity, temperature and struction and operation of the ventilation ventilation rates. systems to assure they work as designed, Professor P. Ole
48、 Fangcr, Technical and 3) to improve the knowledge base of Jniversity of Denmark, presented find- designers and subcontractors so that each ings that provide an understanding of the underslands the implications of the con- influence of relative humidity on health struction and operation of building
49、sys- and conilbi-t, specifically the importance orcontrolling the enthalpy of indoor air at a moderate level by maintaining air tem- perature and relativc humidity at a low level. “The cooling power of air and oc- cupants thcrmal comfoi-t are larger when enthalpy is lower. Occupants perceive the air as fresh as it cools the respiratory tract with each breath,” Fanger said. The findings of the study will have an impact on the design of systems, said Fanger. Existing ventilation standards assume that perceived air qualities and See IAQ Con
