The air duct distribution network is an important component of hvac installations, helping to significantly reduce energy costs and reduce noise nuisance generated by. Number one is the heating and cooling load calculation using a protocol like accas manual j or the ashrae handbook of fundamentals. Table 1 in accas manual j lists design con ditions for locations in the u. A comprehensive duct layout indicating sizes, design airflows, pressure class, and routing of the duct system. The popular and accurate procedure has been revised to include updated and expanded vav guidance, with detailed examples. It delivers an schematic drawing of the duct system including locations and sizes of trunklines, branch ducts, outlet registers, an inlet grilles. Hvac systems design handbook, fifth edition, features new information on energy conservation and computer usage for design and control, as well as the most recent international code council icc mechanical code requirements. The fundamentals of duct system design mcgill airflow. Design guide for heating, ventilating, and air conditioning systems. When applied to airflow in ducts, the flow work or static energy is represented by the static pressure of the air, and the velocity pressure of the air represents the.
Ducts that are not well designed result in discomfort, high energy costs, bad air quality, and increased noise levels. Duct design clicking on a companys name will take you to their web site. The procedures of residential hvac design see figure 1 are covered in detail by a series of. Fellow ashrae 0 f the three duct design procedures recommended by the 1997 ashrae handbookfundamentals, only the tmethod incorporates lifecycle cost. Take the velocity of air in the main duct a as 8 ms for both the methods. Price has long been innovative in the presentation of technical content and product information.
The application of its contents for the design of an air distribution system lies exclusively at the. Ansismacna 0062006 hvac duct construction standards. The purpose of residential ductwork design is to properly distribute the airflow, produced by your heatingcooling system, to your house. In addition to the basic engineering guidelines for the sizing of hvac ductwork. Choosing the rightsized duct is critical to maintain proper air flow in the system. Understanding basic residential ductwork design please note. Starting with the original authors suggested thought process for analyzing typical problems, the reader is then exposed to a buzzword of our time. The application of its contents for the design of an air distribution system lies exclusively at the discretion of the system designer. This 2017 va hvac design manual for the department of veterans affairs va healthcare facilities is the only detailed design requirements manual for va. Further considerations duct sizing methods there is no single duct sizing method that will inherently give the best duct design.
We saw a need to present the evergrowing content of our product catalog in a more efficient way, so the next innovative step for price was to create the price engineers. In addition, the physical parameters of the duct, duct airflow, and uv installation have the potential to affect both the irradiance and the microorganisms response to it. Smacna cad standard second edition v notice to users of this publication 1. We saw a need to present the evergrowing content of our product catalog in a more efficient way, so the next innovative step for price was to create the price engineers hvac handbook. Duct systems are designed to properly distribute air throughout a building. As is the case with upperroom uv installation design, the design parameters for uvc in induct applications are not simple because of some uncertainty in. The ashraefundamentals handbook contains hvac design criteria for most countries around the world. Related commercial resources ashrae handbook fundamentals chapter.
Compliance to the design manual, which promulgates minimum performance design standards for va owned and leased. It provides access to frequently needed information. It delivers an schematic drawing of the duct system including locations and sizes of trunklines, branch ducts, outlet registers, an. Engineering cookbook a handbook for the mechanical designer third edition this handy pocket reference is a token of loren cook companys appreciation to the many fine mechanical designers in our industry. Design the duct system using a velocity method, and b equal friction method. Duct design quick introduction duct sizing tools and methods recommended duct velocities and noise effects.
Introduction to design of industrial ventilation systems. Wraps incorporate an aluminium foil facing that acts as a vapour barrier. Principle of duct design in hvac systems cedengineering. The course concludes with the basic instructions for filling out a. These systems are notorious for consuming more energy than is necessary to properly heat. Airah da3 or the airah technical handbook more available in the ashrae handbook or smacna obtain other duct fittings pressure losses from manufacturers such as duct heaters, dampers, filters, grilles, coils, etc calculated by the following formula derived from bernoullis. Youve got to know how much heating and cooling you need for each room in btuhr. The length of duct used for design purposes that includes the. Below is a simple model for determining duct sizes. Design cfm 4 cfm 6 cfm 8 cfm 10 cfm 12 60 6x4 60 4x6 90 4x8 120 4x10 150 4x12 90 8x4 110 6x6 160 6x8 215 6x10 270 6x12 120 10x4 160 8x6 230 8x8 310 8x10 400 8x12 150 12x4 215 10x6 310 10x8 430 10x10 550 10x12 180 14x4 270 12x6 400 12x8 550 12x10 680 12x12. Highvelocity hv duct systems are characterized by air velocities in the range of 2500 to 3500 fpm.
Small hvac system design guide overview 1 overview this design guide focuses on packaged heating, ventilation and air conditioning hvac syst ems up to 10 tons per unitthe most common hvac systems for small commercial buildings in california. Detailed illustrations, tables, and essential hvac equations are also included. Ashrae 2009 handbookfundamentals, chapter 20, space air diffusion. Small hvac system design guide new buildings institute. The basic principles of duct design, part 1 energy vanguard. This will provide the knowledge necessary to recognize possible design errors and understand the effects of various design. The level 2 duct design tdp will present many areas of design enhancement, such as smacna duct construction standards, duct design code requirements, fitting selection using loss coefficients, avoiding acoustic issues, unique vav system duct features, and using life cycle cost analysis as a design criteria. Insulation can also be installed on the inner wall of the duct duct liners, as glass wool duct wraps or duct slabs faced with a glass matting or mesh providing acoustic insulation and strengthening the inner face of the duct. More available in the ashrae handbook or smacna obtain other duct fittings pressure losses from manufacturers such as duct heaters, dampers, filters, grilles, coils, etc. Heat conduction and thermal resistance for steady state conditions and one dimensional heat transfer, the heat q conducted through a plane wall is given by. Fellow ashrae 0 f the three duct design procedures recommended by the 1997 ashrae handbook fundamentals, only the tmethod incorporates lifecycle cost. This document is not a procedural stepbystep set of instructions on how to create a duct design. The types of fittings to be used based on the designers calculations of fitting losses i. This course will discuss the basic fundamentals and principles of air conditioning duct design and layout.
No part of this work may be reproduced or used in any form or by any means graphic, electronic, or mechanical, including photocopying. The fourth edition of hvac systems duct design presents the basic methods and procedures required to design hvac air distribution systems. Designing a duct system is important but there are a few critical steps that come first. The ansi recognized national standard for residential hvac duct design will help you design a duct system in less time. Consequently, the total pressure or total energy of air flowing in a duct system is generally equal to the sum of the static pressure and the velocity pressure. Oct 08, 2019 price has long been innovative in the presentation of technical content and product information. This manual provides the hvac system designer detailed information on duct design and u. Paul guyer is a registered civil engineer, mechanical engineer, fire protection engineer, and architect with over 35 years experience in the design of buildings and. This method requires many computations, which makes noncost optimizing techniques more attractive. Design cfm 4 cfm 6 cfm 8 cfm 10 cfm 12 60 6x4 60 4x6 90 4x8 120 4x10 150 4x12 90 8x4 110 6x6 160 6x8 215 6x10 270 6x12 120 10x4 160 8x6 230 8x8 310 8x10 400 8x12 150 12x4 215 10x6 310 10x8 430 10x10 550 10x12 180 14x4 270 12x6 400 12x8 550 12x10 680 12x12 210 16x4 320 14x6 490 14x8 670 14x10 800 14x12 240 18x4 375 16x6 580 16x8 800 16x10 950.
A practical approach to design, implementation, connolly, t. Handbook of heating, ventilation and air conditioning. This information should be consulted to ensure that the proper type and location of duct system is selected for the structure in question. This 3hour hvac training online video series provides guidance on how to properly use a friction chart andor accas duct slide rule values for sizing duct in the field. Lowvelocity ductwork design is very important for energy efficiency in air distribution systems. Our manual d calculation service, is a complete custom duct design for your residential project. Leaktight laser welded seams, instead of lockform or spiral duct which badly leaks and allows debris harbors and snag opportunities. Hvac chiller systems handbook pdf a free and simple book introducing hvac chillers.
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