Document qmXOv69j6Q6Gm1b7eo3w2o11E

Copyright 1959 BY THE American Society of heating and Air-Conditioning engineers, Inc. AND BY IT Dedicated to the Advancement of The Profession and Its Allied industries text and illustrations are fully pro tected BY COPYRIGHT AND NOTHING THAT APPEARS MAY BE REPRINTED EITHER WHOLLY OR IN PART WITHOUT SPECIAL PERMISSION. Printed and Bound by Waveblt Press, Inc. BALTIMORE MARYLAND S PREFACE TO THE 37th EDITION The Heating Ventilating Air Conditioning Guide, 1959, has been enlarged to 8M x 11 inch page size for the purpose of providing additional space for new technical text and for enlargement of many il lustrations, working charts, and tables. The use of larger type and open spacing in tables will be of par ticular advantage, for instance, in selecting neat transfer coefficients for various types of building construction or finding degree days for various cities. This edition has 286 new or revised diagrams and charts. In most cases the enlarged page size has made it possible to place illustrations very close to their first mention in the text. Five new chapters have been added on the follow ing subjects: (1) high-temperature water systems, (2) the heat pump, (3) evaporative apparatus for heat rejection, (4) evaporative air cooling and humidifica tion, and (5) snow melting. Outstanding improvements made in chapters con tinued from tne previous edition include (1) new out door winter design temperatures based on probability of occurrence of various temperatures, (2) new steam pipe sizing charts and tables based on Moody friction data for steam flow, (3) a revised table on gages and construction of air ducts including low-, medium-, and high-pressure ducts, (4) revised information and illustrations for unit ventilators and their applica tion, (5) a rewritten chapter on automatic control with new illustrations of control applications, (6) general revision of the information on sorbents; in cluding their use at elevated pressures, (7) data on heat transfer coefficients for ventilated attics, (8) revised information on sound absorption in ducts and plenums, noise levels, and diffuser noise, (9) up-todate values for maximum allowable concentration of .contaminants in occupied spaces, (10) a new section on the absorption refrigeration system, (11) a new section on the gas-fired year-round residential air con ditioner, (12) new data on duct construction for resi dences, (13) a revised discussion of fuel utilization, efficiency, and consumption, (14) a rewritten chapter on school systems, and (15) additions and changes in the list of codes and standards. More detailed information regarding the changes in the various chapters: Chapter 7--Air Contaminants. Additions and re visions have been made in the tables of maximum allowable concentration of toxic gases, vapors, dusts, fumes, and mists, in order to have these values con form to those adopted by the American Conference of Governmental Industrial Hygienists in 1958. Chapter 9--Heat Transmission Coefficients of Build ing Materials. A section on ventilated attic coeffi cients, with, examples, has been added. The section on the practical use of overall coefficients has been re vised. The tables of heat transmission coefficients for various building constructions have been enlarged to facilitate their use. All wall and roof constructions have been numbered to aid in identifying"and referring to the coefficient for a particular construction. Chapter 10--Moisture in Building Construction. The information on moisture migration and its calcu lation has been revised. The discussion of condensa tion in cooled structures has been extended. Chapter It--Heating Load. The data on winter out door temperatures have been revised to show as de sign values for the United States the minimum aver age daily temperatures that have the probability of occurring once in 40, 20, 13, 10, or 5 years as deter mined from U. S. Weather Bureau records. The dis cussion of design temperatures has been rewritten to explain the use of these new values. The tables have been enlarged in type and size for easier readability. Chapter IS--Unit Ventilators and Unit Heaters. The discussion of unit ventilators has been enlarged and thirteen new illustrations have been added. The illustrations of piping connections to unit' heaters have also been revised. Chapter 16--Unitary Air-Conditioning Equipment. A section discussing the features, design considera tions, selection, ana installation of room air condi tioners has been added. Chapter 17--Electric Heating. This chapter was re written to include information on present heating units and methods of use. Chapter 18--Warm Air Heating Systems. The infor mation on ducts has been revised to include recom mended gages for residential systems. Chapter tO--Atr Distribution. The sections on prin ciples of air distribution and on ventilating jets have been rewritten and simplified. Chapter tl--Air Duct Design. A revised section on construction includes data on high-, medium-, and low-pressure ductwork, coordinated with the recom mendations of the Sheet Metal and Air Conditioning Contractors National Association. The charts for friction loss in ducts and the table of equivalent sizes of round and rectangular ducts have been enlarged. Chapter tS--Sound Control. Data on noise levels in offices have been added. The section on noise from axial-flow fans has been enlarged. New information is given on diffuser noise. The sections on sound at tenuation in ducts and plenum absorption have been revised. Chapter 96--Steam Heating Systems. The informa tion on steam pipe sizing has been rewritten to include a new basic chart (0 to 200 psig) based on the Moody' friction data which take into account the Reynolds umber and its effect on the friction factor, and to include also new charts for 30. 50, 100, and 150 psig and tables for 3.5 and 12 psig. (The new information, charts, and tables were prepared by the ASHAE Research Laboratory under the direction of the Tech nical Advisory Committee on Hot Water and Steam Heating.) The section on pressure-reducing valves has been enlarged by the addition of information formerly given in the chapter on District Heating. Chapter 98--Hot Water Heating Systems. A new chart for available gravity head has been added. Chapter 99--High-Temperature Water Systems. A new chapter has been odaed giving a general idea of the principles and practices that apply to high-tem perature systems and discussing significant considera tions for designing these systems. Many new illustra tions showing piping arrangements were used. Chapter 34--Automatic Fuel-burning Equipment. There has been a general revision of this chapter to bring the information up-to-date. A new chart for calculating friction drop or capacity for gas flow in piping has been added. Chapter 36--Heating Boilers, Furnaces, and Space Heaters. The data on steel boilers have been improved and enlarged- Chapter 37--Estimating Fuel Consumptionfor Space Heating. The former section on seasonal efficiency has been replaced by a new section on Efficiency of Utili zation and the section on Calculated Heat Loss Method has been rewritten. Chapter 38--Refrigeration. The information on ab sorption systems has been revised and new illustra tions have been added.