Ashraecertified Hvac Designer (CHD) [PDF]

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CERTIFICATION STUDY GUIDE

CERTIFIED HVAC DESIGNER (CHD)

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CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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ACKNOWLEDGEMENTS

The ASHRAE Certification Committee would like to thank the ASHRAE Foundation Board of Trustees, without whose support this Certification Study

Guide would not have been possible. The Foundation’s commitment to

supporting an innovative, resource-rich study guide, which leverages instructional design best practices, will help ensure effective adult learning that drives desired outcomes and helps HVAC designers work toward achieving their CHD certification goals.

CONTRIBUTORS

ASHRAE would like to thank the Certified HVAC Designers who contributed written materials, technical expertise, and editorial comment in creation of this study guide.

Nissun Feiner, C.Tech, CHD

Delta-T Designs Inc.

Kyle E. Koval, CHD

East Hills Engineering Associates LLC Joshua Mee, CHD

Wendel Companies Ahmad F. Shaar, BCXP, BEMP, CHD, HBDP, HFDP, OPMP

MAG International

Roger Tiguelo, CHD

GRG Prime Engineering Solutions Co

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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CONTENTS INTRODUCTION ....................................................................................... 6

How to Use This Study Guide ................................................................ 7 CHD Exam Preparation Resources ..................................................... 1 0

SECTION 1 .1 : DOMAIN 1 , SYSTEM DESIGN, TASKS A-F .................. 1 2

Overview .............................................................................................. 1 2 Quick Quiz, Domain 1 , Section 1 .1 , Tasks A-F.................................... 1 4 Self-assessment .................................................................................. 1 5

SECTION 1 .2: DOMAIN 1 , SYSTEM DESIGN, TASKS G-L .................. 1 7 Overview .............................................................................................. 1 7 Quick Quiz, Domain 1 , Section 1 .2, Tasks G-L ................................... 1 8 Self-assessment .................................................................................. 1 9

SECTION 1 .3: DOMAIN 1 , SYSTEM DESIGN, TASKS M-R .................. 21

Overview .............................................................................................. 21 Quick Quiz, Domain 1 , Section 1 .3, Tasks M-R ................................... 22 Self-assessment .................................................................................. 23

SECTION 1 .4: DOMAIN 1 , SYSTEM DESIGN, TASKS S-Z ................... 25

Overview .............................................................................................. 25 Quick Quiz, Domain 1 , Section 1 .4, Tasks S-Z.................................... 26 Self-assessment .................................................................................. 27

DOMAIN 1 : SYSTEM DESIGN PRACTICE EXAM QUESTIONS ........... 30 SECTION 2: DOMAIN 2, DESIGN CALCULATIONS ............................. 39 Overview .............................................................................................. 39 Quick Quiz, Domain 2, Tasks A-J ........................................................ 40 Self-assessment .................................................................................. 41

DOMAIN 2: DESIGN CALCULATIONS PRACTICE EXAM QUESTIONS ................................................................................................................. 43 SECTION 3: DOMAIN 3, PROCEDURAL ............................................... 49 Overview .............................................................................................. 49 Quick Quiz, Domain 3, Tasks A-K ....................................................... 50 Self-assessment .................................................................................. 51

DOMAIN 3: PROCEDURAL PRACTICE EXAM QUESTIONS ............... 53

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SECTION 4.1 : DOMAIN 4, COORDINATION, TASKS A-J .................... 56

Overview .............................................................................................. 56 Quick Quiz, Domain 4, Section 4.1 , Tasks A-J .................................... 57 Self-assessment .................................................................................. 58

SECTION 4.2: DOMAIN 4, COORDINATION, TASKS K-U ................... 60

Overview .............................................................................................. 60 Quick Quiz, Domain 4, Section 4.2, Tasks K-U ................................... 61 Self-assessment .................................................................................. 62

DOMAIN 4: COORDINATION PRACTICE EXAM QUESTIONS ............ 64 MY CHD CERTIFICATION EXAM STUDY MAP .................................... 69

Task Notes ........................................................................................... 69 Study Plan ........................................................................................... 76

PRACTICE EXAM QUESTIONS: ANSWER KEY .................................. 77

Domain 1 : System Design ................................................................... 77 Domain 2: Design Calculations ............................................................ 78 Domain 3: Procedural .......................................................................... 79 Domain 4: Coordination ....................................................................... 79

APPENDIX .............................................................................................. 80

Common HVAC Design Formulas ....................................................... 80

GLOSSARY ............................................................................................. 89

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INTRODUCTION ASHRAE is an international membership society committed to the advancement of the arts and sciences of heating, ventilation, air-conditioning, and refrigeration to serve humanity and promote a sustainable world. The Certified HVAC designer (CHD) certification program supports this mission by validating job competency as understood in internationally recognized technical information, reflecting the best practices that lead our industry.

PURPOSE OF THE CHD CERTIFICATION The CHD certification program validates competency of the HVAC designer, working under the responsible charge of an engineer, to do the following: Design HVAC systems to meet building/project requirements, including load calculations, equipment selection and sizing, mechanical equipment room design, duct and piping design, and layout for the development of HVAC plans for permit and construction.

This Study Guide provides a framework and tools to help you self-assess your knowledge in HVAC design and create a customized, self-paced study plan for the CHD exam. ASHRAE offers numerous resources in the field. The Study Guide will help you target which resources are most beneficial based on your own professional development needs. In this Study Guide, you, the candidate, are expected to evaluate your personal skills and qualifications against numerous Tasks broken down into individual Domains. Depending on your experience level, some of these Tasks may be daunting and unfamiliar. If that is the case, consider it an opportunity for growth and devote extra attention to these matters. David Underwood, P. Eng., 201 5201 6 ASHRAE President, once said that “we in the engineering community

More information about the CHD credential and eligibility criteria can be found on the ASHRAE website and in the CHD Candidate Guidebook.

are in the solutions industry.” Based on this statement, it is your job to identify

problems and produce solutions. The Tasks included in Domains 1 -4 represent the skills necessary to produce solutions for HVAC-related problems, and this Study Guide represents your opportunity to fill gaps in your knowledge or experience base.

Using navigation buttons at top of screen: The buttons located at the top of each page allow you to navigate through this document. Click on these buttons to take you Back to view the last page you were on or to the First Page, Previous Page, Next Page, or Last Page. The Glossary button provides a direct link to the full glossary.

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

Clicking links in this document will open in a browser window. You will need to navigate back to the PDF to pick up where you left off.

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THE OVERARCHING GOALS OF THE STUDY GUIDE ARE TO: • • • •

Provide a framework and tools for customized, self-paced exam preparation Focus your review on key elements of recommended exam preparation resources Review knowledge needed to design HVAC systems to meet building/project requirements Build knowledge and skills across the four (4) Domains of the CHD exam, which are:

Domain 1 : System Design Domain 2: Design Calculation Domain 3: Procedural Domain 4: Coordination • • •

Identify key terms and concepts used by HVAC designers Provide the opportunity for you to test your acumen and readiness for the CHD exam Help you assess your own individual core content strengths and weaknesses, and build a study map customized for your needs

How to Use This Study Guide This Study Guide is designed as a workbook that contains tools you can use to assess what you need to focus on as you prepare to take the exam. The Study Guide is organized by Domains and Tasks. There are four Domains total, some of which have numerous Tasks (Domain 1 has 26 Tasks, for example), so we’ve broken them down into segments. The CHD certification exam was developed to assess your competence to perform each of these Tasks as organized under each Domain, so this is a great way to organize your study leading up to the exam and to also build and validate your knowledge, skills, and abilities as an HVAC designer. ASHRAE offers numerous resources to help you study for the CHD certification exam; however, which resources do you need to review to prepare for the exam? The tools in this Study Guide link the Domains and Tasks with the resources available from ASHRAE to help you review and study the content. The tools will also help you determine which Tasks you need to focus upon. So, for example, if through the Self-assessment and Quick Quiz contained herein you discover that you have limited knowledge of Domain 1 : System Design, Task A: Size supply, return, and exhaust ducts, the Study Guide will direct you to the 201 7 ASHRAE Handbook Fundamentals, Chapter 21 .

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ASHRAE Resources are listed in this Study Guide and are available in the ASHRAE Bookstore

Study Tools I n th i s S tu d y G u i d e yo u wi l l fi n d th e fo l l o wi n g to o l s fo r e ach D o m ai n th at wi l l

help you assess what you already know, and importantly, what you don’t kn o w, s te p- by- s te p:

•

Qu i ck Qu i z

•

S e l f- as s e s s m e n t, i n cl u d i n g th e Tas k- by- Tas k R e s o u rce G u i d e , wh i ch wi l l d i re ct yo u to

resources you can use to study, including “deep dive”

re s o u rce s i n s o m e i n s tan ce s yo u can u s e to d e l ve d e e pe r i n to th at to pi c

•

P racti ce E xam Q u e s ti o n s

•

S tu d y M ap

U s e d to g e th e r, th e

study tools in the Guide and ASHRAE’s resources

wi l l

h e l p yo u cre ate a targ e te d , cu s to m i z e d s tu d y pl an bas e d u po n yo u r o wn n e e d s . Yo u wi l l n o te th at we h ave b ro ke n s o m e D o m ai n s i n to m u l ti pl e s e cti o n s to h e l p yo u pace yo u rs e l f th ro u g h th e m ate ri al .

Yo u wi l l s tart e ach s e cti o n by taki n g a Qu i ck Qu i z wh i ch wi l l h e l p yo u te s t yo u r kn o wl e d g e o f ke y te rm s an d co n ce pts fo r th at s e cti o n . N e xt, yo u wi l l co m pl e te a S e l f- as s e s s m e n t to captu re th e are as yo u n e e d to fo cu s u po n as yo u s tu d y fo r yo u r ce rti fi cati o n e xam . Th e s e to o l s wi l l h e l p yo u as s e s s yo u r kn o wl e d g e an d o rg an i z e yo u r s tu d y o f th e co n te n t.

You’ll find instructions for how to use each study tool throughout this Study , but here’s an overview: Guide

Using the Study Guide and ASHRAE Resources Together We re co m m e n d u s i n g th e s tu d y to o l s fo r e ach D o m ai n to g u i d e yo u r co u rs e o f s tu d y an d h e l p yo u pre pare fo r th e C H D e xam :

STEP

1

STEP

R e ad th e Ove rvi e w an d take th e Qu i ck Qu i z an d S e l fas s e s s m e n t fo r e ach s e cti o n o f th e S tu d y G u i d e , s tarti n g wi th D o m ai n 1 , Tas ks A- F.

R e vi e w th e AS H R AE R e s o u rce s fo r e ach Tas k as o u tl i n e d i n th e

2

Tas k- by- Tas k R e s o u rce G u i d e i n cl u d e d i n th e S e l f- as s e s s m e n t, fo cu s i n g yo u r i n i ti al re vi e w o n tas ks yo u m arke d as " s o m e wh at" o r " n o t ve ry" co n fi d e n t. R e co rd n o te s abo u t th e to pi cs yo u n e e d to s pe n d ti m e s tu d yi n g .

STEP

3

Wh e n yo u h ave co m pl e te d yo u r fi rs t fu l l re vi e w o f al l fo u r D o m ai n s an d th e s tu d y to o l s fo r e ach o n e , re tu rn to th e S tu d y G u i d e to co m pl e te yo u r S tu d y M ap. Th i s fi n al s tu d y to o l wi l l h e l p yo u m ap o u t yo u r co u rs e o f s tu d y l e ad i n g u p

to th e ce rti fi cati o n e xam .

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Practice Exam Questions The Study Guide also includes Practice Exam Questions, organized by Domain. You can use these in several ways: • As a pre-test to check your baseline knowledge • As a post-test after completing your review to see how you might do on the exam • As a study and practice tool leading up to the exam, to help check your progress The answer key in the back of the Study Guide includes feedback with the Domain and Task number to help you go back and revisit the content as needed. Remember, you can find the right resource for each Task in the Self-assessments, which include a Task-by-Task guide to the ASHRAE Resources.

Glossary and Search Glossary terms are defined within the text. Click any bolded term to see its definition. You can also access all of the terms at any time by navigating to the glossary by clicking this button.

At any time you can search the Study Guide to find terms or concepts you want to study or review by clicking here.

Evaluation We want to hear from you! Please click this link to complete an evaluation of this Study Guide when you have completed it. CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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CHD Exam Preparation Resources CHD RESOURCES

ASHRAE publications available to help you prepare for the CHD examination may be purchased in the ASHRAE Bookstore: https://www.techstreet.com/ashrae/index.html.

Publications

Primary Publications • • •

201 9 ASHRAE Handbook—HVAC Applications 201 7 ASHRAE Handbook—Fundamentals 201 6 ASHRAE Handbook—HVAC Systems & Equipment

Secondary Publications • • • • • • • • • •

ANSI/ASHRAE Standard 1 5, Safety Standard for Refrigeration Systems and Designation and Classification of Refrigerants ANSI/ASHRAE Standard 55, Thermal Environmental Conditions for Human Occupancy ANSI/ASHRAE Standard 62.1 , Ventilation for Acceptable Indoor Air Quality ANSI/ASHRAE/IES Standard 90.1 , Energy Standard for Buildings Except LowRise Residential Buildings Standard 90.1 User's Manual ANSI/ASHRAE/IES Standard 202, Commissioning Process for Buildings and Systems ANSI/ASHRAE Standard 209, Energy Simulation Aided Design for Building Except Low-Rise Residential Buildings ASHRAE Guideline 36, High-Performance Sequences of Operation for HVAC Systems Principles of Heating, Ventilating, and Air-Conditioning Air-Conditioning Systems Design Manual, 3rd Edition

ASHRAE Learning Institute (ALI) and eLearning Center Courses • The ASHRAE Learning Institute (ALI, https://www.ashrae.org/professionaldevelopment) and ASHRAE eLearning On Demand (https://www.ashrae.org/professional-development/elearning-on-demand) offer a wide range of archived, online courses (https://www.techstreet.com/ashrae/subgroups/48292), professional development seminars, and short courses on ASHRAE Standards and Guidelines. ASHRAE also offers training for companies or chapters. • CHD Practice Exam https://store.lxr.com/product.aspx?id=1 745

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Codes •

I CC,

International Fire Code

•

I CC,

International Building Code

•

I CC,

International Mechanical Code

•

I CC

•

N FP A 1 0 1 ,

Life Safety Code

•

N FP A 9 2 A,

Standard for Smoke-Control Systems Utilizing Barriers and

–

201 8,

International Green Construction Code (IgCC)

Pressure Differences

•

N FP A 9 2 B ,

Standard for Smoke Management Systems in Malls, Atria, and

Large Spaces

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DOMAIN 1 , TASKS A-F

SECTION 1 .1 : DOMAIN 1 , SYSTEM DESIGN, TASKS A-F Overview I n D o m ai n 1 , yo u wi l l re vi e w th e Tas ks re l ate d to th e

art

o f H VAC , i n vo l vi n g

th e co n ce ptu al i z ati o n an d h i g h e r- l e ve l d e s i g n . At th i s s tag e , yo u r d e s i g n be g i n s wi th a bl an k can vas bu t b e g i n s to m o ve fro m abs tract i n te n t, to a s o l i d fo u n d ati o n o n wh i ch th e re s t o f yo u r d e s i g n wi l l bu i l d .

Li ke an y art, H VAC can al s o be s u b j e cti ve . I t i s a g i ve n th at yo u n e e d to h e at, co o l , ve n ti l ate , e tc. , bu t th e s e are th e e n d , n o t th e m e an s . Th e s ki l l s o u tl i n e d i n D o m ai n 1

are wh e re yo u e xe rci s e yo u r cre ati vi ty; yo u r co m pe te n cy i n th e s e

s ki l l s wi l l be wh at s e ts th e m as te r pai n te r apart fro m th e am ate u r h o bbyi s t.

Tas ks A- F wi l l te s t yo u r abi l i ty to b re ak o u t yo u r co n ce pt i n to i n d i vi d u al s e g m e n ts th at can be e xpan d e d u po n l ate r.

How these concepts might apply day-to-day S ay yo u are wo rki n g o n a s i n g l e - l e ve l o ffi ce bu i l d i n g ; yo u m i g h t n e e d to l o o k at th e fo l l o wi n g facto rs :

•

C an yo u i d en ti fy wh i ch ro o m s h ave co m m o n o p e rati n g co n d i ti o n s ?

•

B as e d o n bu i l d i n g o ri e n tati o n an d l o cati o n , can yo u i n fe r wh i ch o ffi ce s wi l l b e h ave d i ffere n tl y d u ri n g d i ffe re n t ti m e s o f th e d ay?

By identifying each room’s unique demands, you can group them together to d e ve l o p a

zoning distribution systems

e q u i p m e n t an d

pl an , bu t yo u are al s o abl e to l o g i cal l y be g i n to l ay o u t yo u r .

I n ad d i ti o n , yo u wi l l n e ed to i d e n ti fy an d u n d e rs tan d th e fo l l o wi n g :

•

Wh at i s th e be s t way to ro u te s u p pl y an d re tu rn d u cts to e ffe cti ve l y s e rve th e s pace s , wh i l e u s i n g th e l e as t am o u n t o f e n e rg y?

•

Wh at i n te rfere n ce s o r co o rd i n ati o n wi th o th e r d i sci pl i n e s can yo u e xpe ct?

•

Wh e re d o yo u re q u i re exh au s t o r fre s h ai r?

•

C an yo u i d en ti fy th e be s t l o cati o n fo r m e ch an i cal e q u i pm e n t fo r s e rvi ce abi l i ty o r n o i s e co n s i d e rati o n ?

•

D o yo u u n d e rs tan d th e d i ffe re n ce s i n te ch n o l o g i e s we l l e n o u g h th at yo u h ave a fe e l i n g fo r wh i ch s ys te m type l e n d s i ts e l f be s t to th i s appl i cati o n ?

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DOMAIN 1 , TASKS A-F At this stage, everything is still vague; nothing is sized and no loads are determined. You will not begin to perform calculations until Domain 2, but the work that is done here will pave the way for these details to develop. Remember that a building is only as strong as the foundation that supports it, and your knowledge and ability at this stage will affect the outcome of all other work down the line. In addition, your ability to understand and compartmentalize these Tasks will further help you properly communicate your intent to teammates who may be further developing them down the line.

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DOMAIN 1 , TASKS A-F

Quick Quiz, Domain 1 , Section 1 .1 , Tasks A-F Now, let’s test your knowledge of some key

term s/con cepts fou n d i n D om ai n

1 , Tasks A-F. For each d efi n i ti on or con cept, sel ect an d wri te i n th e correct opti on from th e ch oi ces provi d ed .

TERMS

DEFINITIONS

Con trol seq u en ce

1 .

Th e g reatest appl i cati on of ____________________ h as been i n con j u n cti on wi th vari abl e- ai r-vol u m e (VAV)

E xh au st d u cts

Fl ow d i ag ram

system s for cool i n g - on l y servi ces.

2.

Th e ____________________ m easu res th e con trol l ed vari abl e an d tran sm i ts to th e con trol l er a si g n al h avi n g

Peri m eter h eati n g

a pressu re, vol tag e, or cu rren t val u e rel ated by a kn own fu n cti on to th e val u e of th e vari abl e bei n g

Sen sor

m easu red .

3.

Verti cal ____________________ m ay n eed to be exten d ed to red u ce exh au st- to- i n take reci rcu l ati on an d i m prove eq u i pm en t effecti ven ess.

4.

Wh en com pl eti n g testi n g , ad j u sti n g , an d bal an ci n g (TAB) an d com m i ssi on i n g , con si d er posti n g l am i n ated system ____________________ at or ad j acen t to cool i n g an d h eati n g eq u i pm en t i n d i cati n g operati n g i n stru cti on s, TAB perform an ce, com m i ssi on i n g fu n cti on al perform an ce tests, an d em erg en cy sh u toff proced u res.

5.

I n th erm al storag e system s, th e opti m al ____________________ resu l ts from trad e-offs between th e costs of cool i n g th e storag e d u ri n g offpeak h ou rs an d th e cost of m eeti n g th e l oad d u ri n g on peak h ou rs.

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CHECK ANSWERS

DOMAIN 1 , TASKS A-F

Self-assessment

What’s your baseline?

Read and consider each Task and assess your confidence level. Then consult the resources for each Task (especially for those Tasks which you

marked “somewhat” or “not very” confident). You might want to skim the resources on this first pass. Note “deep dive” resources are provided where

appropriate to guide you if want to expand your course of study on that topic. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to

guide you. You’ll use these notes to create your Study Map after you have completed your Self-assessment of all four Domains. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task A: Size supply, return, and exhaust ducts.

❑ Confident ❑ Somewhat

Task B: Prepare HVAC zoning plans and sensor locations in accordance with building design.

❑ Confident ❑ Somewhat

Task C: Prepare control sequences and schematics.

❑ Confident ❑ Somewhat

confident ❑ Not very confident

confident ❑ Not very confident

confident ❑ Not very confident

Task-by-Task Resource Guide

My Notes (Topics, resources, and page numbers I need to spend time studying)

201 7 Fundamentals Handbook, Chapter 21 Deep dive: 201 9 Applications Handbook, Chapter 46 201 9 Applications Handbook, Chapter 48 Deep dive: 201 7 Fundamentals Handbook, Chapter 7 201 9 Applications Handbook, Chapter 43 Deep dive: 201 7 Fundamentals Handbook, Chapter 7; 201 9 Applications Handbook, Chapter 48; ASHRAE Guideline 36, Chapters 4 and 5.

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DOMAIN 1 , TASKS A-F Task D: Design ductwork and piping including shaft and ceiling space requirements.

❑ Confident ❑ Somewhat

Task E: Differentiate and design HVAC system types (e.g., variable air volume [VAV], variable refrigerant flow [VRF], radiant, thermal storage, underfloor systems, perimeter and process systems).

❑ Confident ❑ Somewhat

Task F: Design HVAC flow diagrams.

❑ Confident ❑ Somewhat

❑

❑

❑

confident Not very confident

confident Not very confident

confident Not very confident

201 7 Fundamentals Handbook, Chapters 21 and 22 Deep dive: 201 7 Fundamentals Handbook, Chapter 40 201 6 Systems and Equipment Handbook, Chapters 1 , 2, 3, 4, 6, 1 0, 1 3, 1 6, and 51 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 5, 7, 8, 9, 1 1 , 1 2, 1 4, 1 5, 1 7, 1 8 201 6 Systems and Equipment Handbook, Chapters 2, 3, 4, and 1 3 Deep dive: 201 7 Fundamentals Handbook 1 , 5, 6, 7, 8, 9, 1 0, 1 1 , 1 2, 1 4, 1 5, 1 6, 1 7, and 1 8

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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DOMAIN 1 , TASKS G-L

SECTION 1 .2: DOMAIN 1 , SYSTEM DESIGN, TASKS G-L Overview Tasks G-L build upon the work that was done in Tasks A-F. While at this stage no calculations have been completed, you will narrow in on some of the minutiae that was left out in A-F. These Tasks are critical to carry your design forward and ensure that your final design meets the design intent. Some of the questions you will want to ask include the following: • Looking at your preliminary duct or piping routing, can you refine the paths to minimize pressure loss? • Can you identify points that would allow for fewer elbows or take-offs? • How well do you understand air distribution and grilles/diffusers/registers (GDRs)? • Can you properly select and lay them out to maximize comfort while minimizing draft, noise, and pressure loss? • Once calculations are produced, do you understand HVAC technology well enough that you can select a system to use in this application and to convey your design intent to relevant vendors? • Do you properly understand all these Tasks to the point that you can prepare a detailed design brief and prepare schematics, flow diagrams, etc., to present to relevant stakeholders?

Competency in these Tasks will ensure that you’re able to properly

communicate your design, which is paramount to ensuring that whoever carries your design from paper to the real world will achieve the goals you have set from the beginning.

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DOMAIN 1 , TASKS G-L

Quick Quiz, Domain 1 , Section 1 .2, Tasks G-L Now, let’s test your knowledge of some key terms/concepts found in Domain 1 , Tasks G -L. For each defi n i ti on or concept, select an d wri te i n th e correct opti on from th e choi ces provi ded.

TERMS

DEFINITIONS

Ai r-di ffu si on performance i ndex (ADPI )

1.

du ri ng cooli ng u n i t operati on only,

Ai r-h an dl i ng u n i ts (AH U s)

and space condition control i s u su al l y l i m i ted to u se of room

Dehu m i di fi cati on Desi g n loads

____________________ occu rs

thermostats. 2.

The ____________________ i s a u sefu l tool i n predicti n g ou tl et

Ventu ri tu be

perform ance for fu l l y mi xed systems. 3.

The ____________________ i s a nozzle fol lowed by an expandi n g recovery secti on to redu ce net pressu re loss.

4.

Wh en calcu lati ng _________________, heat losses or g ai ns from th e ai r-di stribu ti on system must be i n clu ded in the total l oad for each room .

5.

____________________ can be one of the m ore complicated pi eces of equ i pmen t to speci fy or order, because a vast array of choi ces are avai lable and there i s no si ng len u m ber i den ti fi er that adequ ately describes the desi red produ ct.

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CHECK ANSWERS

DOMAIN 1 , TASKS G-L

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map

after you have completed your Self-assessment of all four Domains. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task G: Design duct and ❑ Confident fluid systems to minimize ❑ Somewhat pressure loss and resultant confident power requirements. ❑ Not very confident Task H: Select HVAC system based on calculations (e.g., AHUs, fans, pumps, chillers, cooling towers).

❑ Confident ❑ Somewhat

Task I: Design proper air diffusion and devices following codes and standards.

❑ Confident ❑ Somewhat

confident ❑ Not very confident

confident ❑ Not very confident

Task-by-Task My Notes (Topics I Need to Spend Resource Guide time Studying) 201 7 Fundamentals Handbook, Chapters 21 and 22 Deep dive: 201 7 Fundamentals Handbook, Chapters 37 and 39 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 1 , 2, 3, 4, 1 3, 21 , 40, 43, 44 201 7 Fundamentals Handbook, Chapters 1 , 1 7, and 40 201 9 Applications Handbook, Chapter 58 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 20; 201 9 Applications Handbook, Chapter 59; ASHRAE Standard 55, Chapters 6 and 7

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DOMAIN 1 , TASKS G-L Task J: Develop a detailed HVAC design based on the approved preliminary building design concept and site information.

❑ Confident ❑ Somewhat

Task K: Prepare HVAC schematics, plan drawings, elevation views, section views, and installation details.

❑ Confident ❑ Somewhat

Task L: Select diffusers and grilles to meet thermal comfort and ventilation needs and coordinate with architectural plans (e.g., ceiling grid, under floor systems, sidewalls, architectural specialties, transfers).

❑ Confident ❑ Somewhat

❑

❑

❑

confident Not very confident

confident Not very confident

confident Not very confident

Deep dive: 201 6 Systems and Equipment Handbook, Chapters 3, 4, and 28; 201 7 Fundamentals Handbook, Chapters 1 7, 1 8, and 40 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 2, 3, 6, 1 0, 1 3, and 1 4; 201 7 Fundamentals Handbook, Chapter 1 9 201 6 Systems and Equipment Handbook, Chapter 20 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 1 0; 201 7 Fundamentals Handbook, Chapter 9; 201 9 Applications Handbook, Chapter 58; ASHRAE Standard 55, Chapter 5

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DOMAIN 1 , TASKS M-R

SECTION 1 .3: DOMAIN 1 , SYSTEM DESIGN, TASKS M-R Overview I n Tas ks A- L, yo u e val u ate d yo u r abi l i ti e s wi th re g ard to pre l i m i n ary d e s i g n Tas ks wi th i n cre as i n g d e tai l . Tas ks M - R wi l l e val u ate yo u r u n d e rs tan d i n g o f d e s i g n fu n cti o n al i ty, as we l l as d e s i g n s affe cti n g e xi s ti n g bu i l d i n g s .

R e n o vati o n s are o fte n m o re co m pl i cate d th an n e w co n s tru cti o n pro j e cts , as th e d e s i g n e r i s o fte n o pe rati n g wi t h po o r as - bu i l t d o cu m e n tati o n an d i s o fte n u n abl e to acce s s e xi s ti n g d u ct an d pi pi n g d i s tri bu ti o n . Yo u r abi l i ty to co n fi d e n tl y e xe cu te Tas ks M - R wi l l d ras ti cal l y i n cre as e th e l i ke l i h o o d o f pro j e ct s u cce s s wh e n d e al i n g wi th re n o vati o n s an d re tro fi ts . Fo r e x am pl e :

•

C an yo u i n ve s ti g ate an d au d i t th e e xi s ti n g s ys te m d e s i g n s , e val u ate e xi s ti n g e q u i pm e n t, an d d e te rm i n e capaci ti e s u s i n g s u ppo rti n g d o cu m e n tati o n ?

•

Are yo u abl e to u n d e rs tan d pro po s ed ch an g e s to th e bu i l d i n g an d d e te rm i n e h o w th e H VAC s ys te m i s affe cte d ?

•

Are yo u abl e to e ffe cti ve l y co m m u n i cate wh at s ys te m s n e e d to be d e m o l i s h e d o r m o d i fi e d ?

•

Are yo u abl e to re co m m e n d i n te g rati o n o f n e w te ch n o l o g i e s to i n cre as e th e e ffi ci e n cy an d e ffe cti ve n e s s o f th e H VAC s ys te m s ?

•

Wh at u pg rad e s to th e e xi s ti n g s ys te m wi l l be n e ce s s ary to s u i t th e p ro po s e d ch an g e s ?

•

Wh at ch al l e n g e s d o th e s i te co n d i ti o n s p o s e to yo u r pro po s ed d e s i g n ?

•

Wi l l yo u be abl e to re co m m e n d s o l u ti o n s th at wi l l m atch th e l o n g e vi ty o f th e bu i l d i n g i n te rm s o f s e rvi ce ab i l i ty an d fu tu re e xpan s i o n ?

•

Wi l l yo u r s o l u ti o n s pro vi d e re d u n d an cy s trate g i e s to m i n i m i z e d o wn ti m e s d u ri n g m ai n te n an ce ?

D u e to th e n atu re o f re n o vati o n s , an H VAC d e s i g n e r re l i e s h e avi l y o n e ffe cti ve co o rd i n ati o n an d co m m u n i cati o n . Lack o f ad e q u ate pre parati o n d u ri n g th e s e Tas ks d ras ti cal l y i n cre as e s th e l i ke l i h o o d o f co s t an d s ch e d u l e o ve rru n s d u e to po o r d rawi n g s an d m i s s e d s i te co n d i ti o n s an d m ay e ve n j e o pard i z e th e e ffe cti ven e s s o f o ve ral l d e s i g n .

J u s t l i ke Tas ks A- L, p ro pe r fo cu s an d atte n ti o n to th e s e s ki l l s wi l l pay d i vi d e n d s d o wn th e ro ad .

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DOMAIN 1 , TASKS M-R

Quick Quiz, Domain 1 , Section 1 .3, Tasks M-R Now, let’s test your knowledge of some key terms/concepts found in Domain 1 , Tasks M -R. For each defi ni ti on or concept, select an d wri te i n th e correct opti on from th e choi ces provi ded.

TERMS

DEFINITIONS

Ai r deli very equ i pm ent

1.

Li brary, equ i pm ent tech ni cal data sheets and as-

DDC or BAS systems

bu i l t drawi ng s can be obtai ned from the ____________________ and

Mai ntenance m an u al /

____________________ respecti vely.

Operati ng m an u al Predicti ve maintenance

In an existing project’s O&M Documentation

2.

Vi brati on an alysi s to identi fy i mbalances, beari ng wear, and m i sal i g n m en t i s an exampl e of ______________________.

3.

____________________ can monitor, calcu late, and record system statu s, water u se, energ y u se at the m ai n m eter or of parti cu lar end-u se systems, demand, and h ou rs of operati on; as well as start and stop bu i ldi ng systems.

4.

One ____________________ ri si ng i n popu lari ty i s a fan array, whi ch u ses m u l ti ple plu g fans on a comm on

plenum wall , thu s redu ci n g u ni t si ze.

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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CHECK ANSWERS

DOMAIN 1 , TASKS M-R

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map

after you have completed your Self-assessment of all four Domains. NOTE: Task P is based on experience, and there are no Resources available for review or study. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task M: Evaluate ❑ Confident proposed building design ❑ Somewhat concept modifications for confident HVAC implications. ❑ Not very confident Task N: Integrate new system technologies into HVAC design (e.g., variable refrigerant flow [VRF], electronically commutated motor [ECM] control, integrated automation).

❑ Confident ❑ Somewhat

Task O: Research and confirm capacities of existing equipment and obtain shop drawings of existing equipment (e.g., air-handling systems, chillers, cooling towers).

❑ Confident ❑ Somewhat

confident ❑ Not very confident

confident ❑ Not very confident

Task-by-Task Resource Guide 201 7 Fundamentals Handbook, Chapter 1 9 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 2, 3, 4, and 1 8 201 9 Applications Handbook, Chapters 42 and 63 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 4, 7, 1 8, and 45; 201 9 Applications Handbook, Chapters 43 and 65; 201 8 International Green Construction Code, Chapters 7 and 8 201 9 Applications Handbook, Chapters 40

My Notes (Topics I Need to Spend time Studying)

Deep dive: 201 9 Applications Handbook, Chapter 44

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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DOMAIN 1 , TASKS M-R Task P: Prepare HVAC

demolition drawings of the equipment and systems that must be moved or relocated to accomplish retrofit.

Task Q: Recommend

system design options to minimize machine or system downtime (e.g., N+1 , 2N, fan array, direct drive fans, VRF).

Task R: Recommend

system configurations to facilitate future maintenance (e.g., system access, coil pull space, motor replacement, safety concerns).

❑ ❑ ❑ ❑ ❑ ❑

❑ ❑ ❑

Confident Somewhat confident Not very confident

Task P: no recommended chapters

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapter 4

Confident Somewhat confident Not very confident

201 9 Applications Handbook, Chapter 40 Deep dive: 201 9 Applications Handbook, Chapter 60

Deep dive: 201 6 Systems and Equipment Handbook, Chapters 1 , 2, 3, 1 3, 1 8, 21 , and 44

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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DOMAIN 1 , TASKS S-Z

SECTION 1 .4: DOMAIN 1 , SYSTEM DESIGN, TASKS S-Z Overview By this stage of an HVAC design project, you have established a high-level design intent, provided additional detail to help develop and mature the design, reviewed existing conditions, and evaluated different options to suit all these different circumstances. Tasks S-Z will round out the rest of the design by providing needed detail. At this point, you would incorporate calculations (to be reviewed in Domain 2) and integrate them in your design. Tasks that you may want to consider include the following: • Can you adequately prepare drawings and schematics that show distribution branches, piping loops, and system components? • Are you able to identify the need for balancing and flow regulation, as well as specify and document balancing dampers and valves? • Are you able to size and select expansion tanks , heat exchangers, air handlers, and boiler plants? • Are you able to size and select pumps, valves, and fans? These final touches complete your design and finish its journey from abstract intent to a tangible, workable product. At this stage, you should have identified all your conditions, variables, and operating parameters and produced a design that will accurately and deliberately meet those metrics. Once you are satisfied that you are sufficiently competent in Tasks A-Z of Domain 1 , proceed to Domain 2.

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DOMAIN 1 , TASKS S-Z

Quick Quiz, Domain 1 , Section 1 .4, Tasks S-Z Now, let’s test your knowledge of some key terms/concepts found in Domain 1 , Tasks S-Z. For each defi ni ti on or concept, select and wri te i n the correct opti on from the choi ces provi ded.

TERMS

DEFINITIONS

Ai r-si de

1.

A(n) _________________ econom izer uses

2.

____________________ fans may be forward-

Anci llary equ ipm ent Cali brati on

outdoor air to reduce refrig erati on requ irem ents. cu rved, backward-incli ned, or ai rfoi l, and si ng lewi dth/sin g le-inl et (SWSI ) or dou ble-wi dth/dou ble-i nlet

Centri fug al

(DWDI ) . ____________________ i s an energ y analysis tool that u ses vector analysi s to evalu ate al l

Pi n ch technolog y

heating and cooli ng u ti li ti es i n a process. 3.

____________________ i s th e process of com parin g a set of di screte m ag ni tu des or the characteristi c cu rve of a con ti n u ou sly varyi ng m ag ni tu de wi th an oth er set or cu rve previ ou sly establ ished as a standard.

4.

A cen tral plant can be cu stom i zed wi thou t sacri fi ci n g the stan dardizati on, fl exi bi li ty, and perform ance requ i red to su pport the prim ary cooli n g and heating equ i pment by carefu lly selecti ng ____________________, au tomati c control , and faci li ty m anag em en t.

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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CHECK ANSWERS

DOMAIN 1 , TASKS S-Z

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map

after you have completed your Self-assessment of all four Domains. NOTE: This is the last set of Tasks for Domain 1 . Answer the Practice Exam Questions that follow for Domain 1 before moving on to Domain 2. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task S: Design for ❑ Confident balancing air and fluid ❑ Somewhat systems (e.g., balancing confident dampers, balance valves, ❑ Not very self-balancing control confident valves).

Task T: Prepare ductwork and piping flow diagrams to convey the design intent (e.g., primary/secondary systems, pumping and isolation systems, duct loops, exhaust risers with sub-ducts.)

❑ Confident ❑ Somewhat

Task U: Design piping and ductwork layout based on calculated sizing and required routing.

❑ Confident ❑ Somewhat

confident ❑ Not very confident

confident ❑ Not very confident

Task-by-Task Resource Guide 201 9 Applications Handbook, Chapter 39 Deep dive: 201 6 HVAC Systems and Equipment Handbook, Chapter 47; 201 7 Fundamentals Handbook, Chapter 37 201 6 Systems and Equipment Handbook, Chapters 3, 4, 5, 9, 1 0, 1 3, 21 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 1 , 2, 6, 7, 8, 1 1 , 1 2, 1 4, 1 5, 1 6, 1 7, 1 8, and 21 201 7 Fundamentals Handbook, Chapters 21 and 22 Deep dive: 201 7 Fundamentals Handbook, Chapter 38

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

My Notes (Topics I Need to Spend time Studying)

27

DOMAIN 1 , TASKS S-Z Task V: Select expansion tanks.

❑ ❑ ❑

Task W: Select major airside units.

❑ ❑ ❑

Task X: Size major heating plant components.

❑ ❑ ❑

Task Y: Design leakdetection systems.

❑ ❑ ❑

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapter 1 3 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 1 5

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapters 1 , 4, 5, and 1 0 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 2, 3, 6, 7, 8, 9, 1 1 , 1 2, 1 3,1 4, 1 5, 1 6, 1 7, and 1 8

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapter 32 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 3, 5, 1 3, and 1 5

Confident Somewhat confident Not very confident

201 7 Fundamentals Handbook, Chapter 29 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 1 8; ASHRAE Standard 1 5, Chapters 7 and 8

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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DOMAIN 1 , TASKS S-Z Task Z: Select major

cooling plant components: 1 . fans

❑ ❑ ❑

2. coils

❑ ❑ ❑

3. piping

❑ ❑ ❑

4. pumps

❑ ❑ ❑

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapter 21 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 4

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapter 23 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 5, 1 3, and 27

Confident Somewhat confident Not very confident

201 7 Fundamentals Handbook, Chapter 22

Confident Somewhat confident Not very confident

201 6 Systems and Equipment Handbook, Chapter 44 Deep dive: 201 6 Systems and Equipment Handbook, Chapters 5 and 1 3

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DOMAIN 1

DOMAIN 1 : SYSTEM DESIGN PRACTICE EXAM QUESTIONS 1.

CHECK ANSWERS CLEAR ANSWERS

Whi ch desi g n method sh ou ld be u sed to si ze ducts down stream of termi nal boxes, toi l et exhau st du cts, and other l ow-pressu re systems?

2.

3.

A.

equ al fri cti on meth od

B.

stati c fri cti on method

C.

stati c reg ai n method

For du ct sizi ng , th e stati c reg ai n m ethod shou l d be avoi ded for: A.

posi ti ve-pressu re du ct system s

B.

neg ati ve-pressu re systems

C.

l ow-pressu re du ct system s

Whi ch of th e fol l owi n g statem ents i s MOST accu rate reg ardi ng the Task of sequ enci ng h eati n g and cool i ng ? A.

Central fan system s shou ld n ot u se cool ou tdoor ai r i n sequ ence between heati ng and cool i ng .

B.

H eati ng an d cool i ng shou l d be su ppli ed si m u l taneou sl y for h u m i di ty control .

C.

Zoni ng and system sel ecti on sh ou ld el i mi nate, or at l east m in i m i ze, si m u l taneou s h eati ng and cooli ng .

4.

When choosi n g a chi ller, thi s type of system requ i res g reater care i n desi g n of the control system an d con trol sequ ences bu t i s u su al l y m ore effi ci en t. A.

constant fl ow

B.

vari abl e fl ow

C.

vari abl e-pri mary flow

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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DOMAIN 1 5. A control schematic MOST frequently includes which of the following?

CHECK ANSWERS CLEAR ANSWERS

A. description of the layout B. description of the system functions C. layout of the Input/output objects 6. When looking at the schematic of a heating system, the air-distribution system is made up of which two items? A. boiler(s); heating coil(s) B. heating coil(s); zone(s) C. zone(s); boiler(s) 7. Buildings over how many stories high USUALLY require vertical shafts to consolidate mechanical, electrical, and telecommunication distribution throughout the facility? A. 3 B. 5 C. 7 8. When determining the proper accounting of leakage-related impacts on fan energy and space conditioning loads, the recommended MAXIMUM system leakage is what percentage of design airflow. A. 2% B. 5% C. 8% 9. When designing a fluid flow system, there are two concerns that need to be taken into consideration. They are the: A. flow/pressure relationship and the sizing of pipe B. number of joints in the plan and flow/pressure relationship C. number of joints in the plan and the sizing of pipe

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DOMAIN 1 1 0. There are three basi c types of cool i ng only,

variable refrigerant flow (VRF) systems :

heat pump, and ___________.

A.

ai r-cool ed ou tdoor

B.

heat recovery

C.

water-cool ed ou tdoor

1 1 . The th ermal layer of water i n a ch i ll ed-water thermal storag e tank, separati n g warmer water at the top and cool er water at the bottom i s cal l ed wh i ch of the fol lowi ng ? A.

a therm ocl i ne

B.

therm al bri dg i n g

C.

therm al storag e capaci ty

1 2. The fl ow di ag ram of a two-pi pe ch ang e-over system MU ST contai n ________. A.

boi ler, pu m p, and l oad

B.

ch i l l er, boi l er, an d pu m p

C.

ch i l l er, pu mp, and load

1 3. The m ost com mon en g i n eeri n g desi g n fl ow l oss cal cu l ati on sel ects a pi pe si ze based on whi ch of the fol l owi n g ? A.

al l owabl e pressu re drop and desi red fl ow rate

B.

desi g n ed l en g th of pi pe and all owable pressu re drop

C.

desi red fl ow rate and desi g ned leng th of pi pe

1 4. Whi ch of th e fol l owi n g i s the BEST desi g n recom mendati on to m i n i m i ze pressu re loss i n an ai r system ? A.

Avoi d u se of rou nd spi ral du cts.

B.

Rou te du cts as strai g ht as possi bl e.

C.

U se consecu ti ve and close-cou pl ed fi tti ng s.

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 1 1 5. What i s the tem peratu re di fference between th e water en teri n g and the

CHECK ANSWERS CLEAR ANSWERS

water l eavi n g th e cool i ng tower cal led? A.

approach

B.

cool i n g capaci ty

C.

range

1 6. The

occupied zone i s g en eral l y consi dered to be th e room volu me

between th e floor l evel an d ___ above the floor. A.

6 ft/1 . 8 m

B.

8 ft/2. 4 m

C.

1 0 ft/3. 0 m

1 7. I n the very earl y ph ases of bu i ldi ng desi g n, the combi ned m ech ani cal and electri cal space requ i rem ent of m ost bu i l di ng s i s wh at percen tag e of the total bu i l di ng fl oor area? A.

3-5%

B.

6-9%

C.

1 0-1 2%

1 8. The person responsi bl e for selecti ng con trol valves, coordi nati ng th em wi th heat tran sfer devices, and provi di ng a sch edu l e of devi ces and a detail ed conn ecti on schemati c i s whi ch of the foll owi ng ? A.

archi tect

B.

H VAC desi g ner

C.

project eng i neer

1 9. Thi s type of di ffu ser featu res a seri es of open i n gs arrang ed i n a radi al pattern arou n d the center of the di ffu ser face. A.

sl aqu e-face

B.

squ are

C.

swi rl

CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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DOMAIN 1 20. A common application to compare retrofit alternatives for existing buildings is which of the following?

CHECK ANSWERS CLEAR ANSWERS

A. plug loads B. energy modeling C. building orientation 21 . A mathematical model is a description of the behavior of a system. It contains which components? A. input variables, output variables, data driven models B. input variables, output variables, system structure and parameter properties C. system structure and parameter properties, data driven models, output variables 22. This system technology has been used primarily to protect expensive equipment from catastrophic failure, ensure safety, and provide alarms when a measured variable goes outside its acceptable operating range. A. automated-fault detection and diagnosis (AFDD) B. building automation systems (BASs) C. indoor environmental quality (IEQ) 23. Periodically, the capacity of existing buildings may need to be evaluated. Doing so is called _________. A. ongoing commissioning B. recommissioning C. retrocommissioning 24. (P-work experience) _________ are used to indicate overall modifications to existing systems. A. as-built drawings B. demolition drawings C. flow diagrams

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DOMAIN 1 25. To eliminate maintenance and replacement, which type of motor would be MOST appropriate for a fan system? A. electronically commutated motor (ECM) B. belt-drive C. permanent split capacitor (PSC) 26. This type of maintenance schedule is MOST typically used to extend useful life of essential building equipment, such as pumps, air handlers, boilers, ductwork, elevators, and transformers. A. predictive B. preventive C. run-to-failure 27. The built-in benefit of a ____________ is that, when properly field adjusted, all system flow paths have the same head loss. A. automatic flow limiter B. orifice flowmeter C. static balancing valve 28. Dynamic and ________ dampers are the two basic styles of traditional balance dampers. A. motor operated B. pressure independent C. static 29. Parallel pumping arrangements increase what flow characteristic? A. increased flow B. increased head C. redundancy

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 1 30. When designing ductwork there are two (2) methods, static regain and ________.

CHECK ANSWERS CLEAR ANSWERS

A. critical path B. equal friction C. low pressure 31 . What is the approximate MAXIMUM friction loss that should be considered when sizing a traditional piping system? A. 4 ft per 1 00 ft of pipe (400 Pa/m) B. 5 ft per 1 00 ft of pipe (500 Pa/m) C. 6 ft per 1 00 ft of pipe (600 Pa/m) 32. This type of terminal unit is generally applied to areas with higher concentrations of sensible cooling loads and requires elevated chilledwater temperatures. A. chilled beam B. fan-coil unit C. variable air volume (VAV) box 33. This type of expansion tank has a flexible membrane that is inserted between the air and the water. A. bladder B. diaphragm C. open 34. A disadvantage of air-side economizers in some systems is that the unit must be located __________. A. central to the building B. near an indoor wall C. near an outdoor wall

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DOMAIN 1 35. A client is building a new building and wishes to use a high efficiency boiler and the load calculations you performed indicate the building has 1 50,000 Btu/hr/heat loss. Designing around a 40 degree delta T, how many gallons per minute/liters per second of water are required for the system design?

CHECK ANSWERS CLEAR ANSWERS

A. 7.5 gpm/ B. 1 5 gpm/ C. 75.0 gpm/ 36. In which method of refrigerant leak detection, the object to be tested is pressurized with air or nitrogen? A. bubble B. dye C. electronic 37. What is the MOST important selection criterion for condenser fans? A. energy use B. noise level C.

static pressure

38. When selecting a coil, which of the following should be considered? A. air quality B. energy consumption C. space limitations 39. For chilled water, which of the following is the MOST common piping material? A. chlorinated polyvinyl chloride (CPVC) B. steel, galvanized C. steel type F (CW)

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DOMAIN 1 40. Which type of pump is mounted on a horizontal motor supported by the motor or pump foot mountings?

CHECK ANSWERS CLEAR ANSWERS

A. close-coupled, single-state, end-suction B. frame-mounted, end-suction C. vertical in-line

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DOMAIN 2

SECTION 2: DOMAIN 2, DESIGN CALCULATIONS Overview I n D o m ai n 1 , yo u we re co n ce rn e d wi th tas ks an d s ki l l s th at we re m o re co n ce pt d ri ve n . Yo u h ad to e s tabl i s h an abs tract d e s i g n i n te n t an d fu rth e r re fi n e i t i n to a fi n al pro d u ct. I n D o m ai n 1 , h o we ve r, yo u we re n o t re al l y co n ce rn e d wi th th e actu al cal cu l ati o n s . I n s te ad , yo u we re fo cu s e d o n wh at yo u d o be fo re an d afte r th e cal cu l ati o n s s tag e .

I f D o m ai n 1

i s th e art o f H VAC , th e n D o m ai n 2 i s ce rtai n l y th e s ci e n ce . Th e

s ki l l s th at are te s te d u n d e r th i s D o m ai n e n s u re th at yo u r d e s i g n ach i e ve s i ts g o al s . I n th i s D o m ai n yo u wi l l e s tabl i s h :

•

H o w m u ch e n e rg y yo u m u s t ad d to o r re m o ve fro m th e s p ace .

•

H o w m u ch fre s h ai r o r e xh au s t th e s p ace re q u i res .

•

D u ct an d pi pe s i z e s to carry th e h e ati n g & co o l i n g m e d i u m s .

•

S ys te m co m po n e n ts to s u i t th e u n i q u e d e m an d s o f d i ffe re n t h e ati n g an d co o l i n g m e d i u m s .

Wh i l e D o m ai n 1

bu i l d s a s o l i d fo u n d ati o n fo r yo u r d e s i g n , th o s e e ffo rts are

was te d i f yo u r cal cu l ati o n s are i n accu rate o r b as e d o n i n co rre ct as s u m pti o n s .

Much like the systems we design, the designer’s skill must be well balanced. I f n o t, th e bu i l d i n g o ccu pan ts are s u re to n o ti ce .

On ce yo u are s ati s fi e d th at yo u are s u ffi ci e n tl y co m pe te n t i n al l o f th e Tas ks i n D o m ai n 2 , m o ve o n to D o m ai n 3 .

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DOMAIN 2, TASKS A-J

Quick Quiz, Domain 2, Tasks A-J Now, let’s test your knowledge of some key terms/concepts found in Domain 2, Tasks A-J. For each definition or concept, select and write in the correct option from the choices provided.

TERMS

DEFINITIONS

CD1 1 -3

1.

A(n) ____________________ pipe operates at the lowest overall stress level.

2.

____________________ ventilation is the intentional movement of air into and out of a building suing fans, ductwork, intake louvers, and exhaust grilles.

3.

____________________ is the normal force per unit area.

4.

Heating calculations use simple worst-case assumptions: no solar or internal gains, and no ____________________ (with all heat losses evaluated instantaneously).

5.

Ventilation ____________________ may be offset with heat recovery equipment.

6.

For pipe sizes 2 in. and over, minimum velocities corresponding to a ____________________ of 0.75 ft/1 00 ft are normally used.

7.

Peak design heating and ____________________ calculations seek to determine the maximum rate of heating and cooling energy transfer at any point in time.

8.

Noise, ____________________, and installation and operating costs all limit the maximum and minimum velocities in piping systems.

9.

____________________ determines the size of a duct, knowing airflow, such that the design velocity is not exceeded.

Cooling load Erosion Head loss Heat load Heat storage Mechanical Pressure Unrestrained

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CHECK ANSWERS

DOMAIN 2, TASKS A-J

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map

after you have completed your Self-assessment of all four Domains. NOTE: This is the only set of Tasks for Domain 2. Answer the Practice Exam Questions that follow for Domain 2 before moving on to Domain 3. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task A: Calculate HVAC ❑ Confident system requirements (e.g., ❑ Somewhat water flows, airflows, pump confident heads, suction heads, expansion compensation). ❑ Not very confident Task B: Assist in the preparation of project estimates for comparative system selection (e.g., installed cost, operating cost, space limitations, water availability, power requirements). Task C: Calculate all piping and ductwork sizing based on flow rates received from the project engineer and adapted in size and route to comply with the existing physical constraints. Task D: Adjust thermal load or HVAC requirement estimates based on modifications to building.

❑ Confident ❑ Somewhat confident ❑ Not very confident

Task-by-Task Resource Guide 201 7 Fundamentals Handbook, Chapters 21 and 22. Deep dive: 201 7 Fundamentals Handbook, Chapters 36 and 39 201 9 Applications Handbook, Chapter 38

My Notes (Topics I Need to Spend time Studying)

❑ Confident 201 7 Fundamentals Chapters ❑ Somewhat Handbook, 21 and 22 confident ❑ Not very confident

Deep dive: 201 7 Fundamentals Handbook, Chapter 39

❑ Confident 201 7 Fundamentals Chapters ❑ Somewhat Handbook, 1 7 and 1 8 confident ❑ Not very confident

Deep dive: 201 7 Fundamentals Handbook, Chapters 3, 9, and 36

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DOMAIN 2, TASKS A-J Task E: Calculate head loss through the critical path.

❑ Confident 201 7 Fundamentals ❑ Somewhat Handbook, Chapter 22

Task F: Calculate heat loads for each assigned space in the building.

❑ Confident ❑ Somewhat

Task G: Calculate the building load heat loss and gain.

❑ Confident ❑ Somewhat

Task H: Calculate external static and total pressures for air-distribution units and specify in the equipment schedule.

❑ Confident ❑ Somewhat

Task I: Calculate ventilation rate requirements by space use, thermal comfort parameters, and air quality per applicable codes and standards.

❑ Confident ❑ Somewhat

Task J: Design piping system to account for various fluid properties (e.g., freeze protection, fluid expansion compensation, fluid density, transfer capacity).

❑ Confident ❑ Somewhat

confident ❑ Not very confident

confident ❑ Not very confident

confident ❑ Not very confident

confident ❑ Not very confident

confident

❑ Not very

confident

confident ❑ Not very confident

Deep dive: 201 7 Fundamentals Handbook, Chapters 21 and 39 201 7 Fundamentals Handbook, Chapters 1 7 and 1 8 Deep dive: 201 7 Fundamentals Handbook, Chapters 1 4, 1 5, 1 6, and 39 201 7 Fundamentals Handbook, Chapters 1 7 and 1 8 Deep dive: 201 7 Fundamentals Handbook, Chapters 3, 9, 1 4, 1 5, 1 6, and 36 201 7 Fundamentals Handbook, Chapter 21 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 21 ; 201 7 Fundamentals Handbook, Chapter 39 201 7 Fundamentals Handbook, Chapters 9, 1 6, and 40 Deep dive: 201 7 Fundamentals Handbook, Chapters 3 and 36 201 7 Fundamentals Handbook, Chapters 3 and 22 Deep dive: 201 7 Fundamentals Handbook, Chapters 9 and 31

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DOMAIN 2

DOMAIN 2: DESIGN CALCULATIONS PRACTICE EXAM QUESTIONS 1.

CHECK ANSWERS CLEAR ANSWERS

A l ou ver i s rated to resi st water penetrati on for veloci ti es u p to 1 000 fpm (5. 1 m /s) an d has 70%

free area. Wh at i s the m axi m u m ai rflow that can

flow throu g h a l ou ver wi th an overal l area of 1 2 ft² (1 . 1 1 m ²) ?

2.

A.

3600 cfm (1 02 m ³/mi n)

B.

8400 cfm (238 m ³/mi n )

C.

1 2, 000 cfm (340 m³/mi n)

An exi sti ng bu i l di ng i s served by a chi ll er plant operati n g at delta T 1 0F (5. 56 C) wi th total chi lled water fl ow 700 U . S. g pm (44. 1 6 L/s) . The bu i l di ng owner deci des to repl ace the chi l ler pl an t wi th a new h i g h perform ance ch i l l er plant, whi l e m ai n tai n i n g th e same total cool i n g capaci ty. The new chi l ler pl an t wi l l operate at delta T 1 4F (7. 78 C) . What i s the TOTAL ch i l l ed water flow of th e new pu m p(s) ?

3.

A.

500 U . S. g pm (31 . 55 L/s)

B.

700 U . S. g pm (61 . 83 L/s)

C.

980 U . S. g pm (44. 1 6 L/s)

1 00 GPM (378 LPM) of water i s pu mped wi th a 2 H P base-m ou n ted pu m p operati ng at 75% effi ci ency. Wh at i s the approxi mate head l oss on the system?

4.

A.

40 ft (1 20 kPa)

B.

60 ft (1 80 kPa)

C.

80 ft (240 kPa)

The preferred relati ve humidi ty ran g e for hu man h ealth and comfort i s between _________. A.

30 and 50%

B.

40 and 60%

C.

50 and 70%

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DOMAIN 2 5. When evaluating a system to recommend to a building owner who intends to own and operate the building 20 years, which of the following systems would have the lowest life-cycle cost ? A. system A, which has an installed cost of $1 00,000 and an annual operating and maintenance cost of $3,500 B. system B, which has an installed cost of $1 25,000 and an annual operating and maintenance cost of $1 ,500 C. system C, which has an installed cost of $80,000 and an annual operating and maintenance cost of $1 ,500 and estimated life span of 1 5 years 6. What is the criterion MOST used for louver sizing? A. maximum free area B. minimum static pressure drop C. water penetration 7. In the formula for velocity,

V=Q/A, A represents which of the following?

A. airflow rate B. cross-sectional area of duct C. total pressure 8. A hot-water heating system is to be designed to operate between 1 20°F and 1 80°F (49°C and 82°C). Which of the following should be avoided as a piping material? A. copper B. steel C. PVC 9. Which equation is used to calculate the time it takes for an incompressible fluid in a horizontal, constant-area conduit to achieve steady flow? A. unsteady Flow B. Bernoulli C. Poiseuille Flow

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 2 1 0. When predi cti n g th e mean respon se of a l arg e grou p of peopl e accordi ng to the ASH RAE therm al sen sati on scale, the

predicted mean vote

(PMV) i n dex i s u sed. I n the PMV equ ati on, L represents: A.

acti vi ty l evel

B.

l en g th

C.

therm al l oad on the body

1 1 . Whi ch of th e fol l owi n g i s the MOST u nknown factor wh en performi ng l oad cal cu lati ons? A.

di m en si on s of th e bu i l di ng

B.

ski l l of bu i l der

C.

infiltration rates

1 2. When cal cu lati ng the al lowable ai r leakag e for each fan system , the recom mend ed percentag e for su pply and retu rn du ctwork secti ons that l eak di rectly to/from the su rrou ndi n g space i s whi ch of the foll owi ng ? A.

2%

B.

3%

C.

5%

1 3. When u si ng th e Darcy-Wei sbach equ ati on and presenti ng i t in h ead or speci fi c energ y form ,

g represents:

A.

accelerati on of g ravi ty

B.

u n i ts conversi on factor

C.

flu i d den si ty

1 4. When cal cu lati ng pressure drop, wh i ch of th e fol lowi ng i nform ati on i s

provided within the manufacturer’s data? A.

flow rate

B.

h ead l oss from equ i pment

C.

valves and fi tti ng s

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 2 1 5. When com pl eti n g heating cal cu l ati ons, wh i ch of the fol l owi ng needs to be taken i nto accou n t? A.

heat gain from i n tern al equ i pment

B.

heat loss throu g h exteri or wall s

C.

solar heat g ai n throu g h exteri or g l azi ng

1 6. When cal cu lati ng the heat g ai n th rou g h an exteri or g l azi n g , i t i s MOST i mportant to kn ow whi ch of the fol lowi ng ch aracteri sti cs? A.

el evati on above sea l evel an d g lass thi ckness

B.

ori entati on and elevati on above sea level

C.

ori entati on and g lass thi ckness

1 7. Whi ch m on th i s u sed to determ in e th e ti me of year when the M AXI M U M h eati n g l oad occu rs? A.

the m on th wi th the h i g h est mean dry bu lb

B.

the m on th wi th the hottest m ean dry bu l b

C.

the m on th wi th the lowest mean dry bu lb

1 8. A space has a total exteri or wal l area of 1 200 ft² (1 1 1 m²) and an i nsu l ati on val u e of R-1 8 (RSI 3. 1 7) . The desi g n ou tdoor h eati ng tem peratu re i s 0° F (1 7. 8° C) and the i nteri or temperatu re i s 70° F (21 . 1 ° C) . Wh at i s the approxi m ate total heat requ i red to offset the l oss throu g h th e wall ? A.

2. 2 M BH (0. 64 kWh)

B.

3. 5 M BH (1 . 03 kWh )

C.

4. 7 M BH (1 . 38 kWh )

1 9. Whi ch of th e fol l owi n g statements i s MOST correct when esti mati ng h eat l oss th rou g h com pl etel y bel ow-g rade stru ctu res? A.

All bel ow-g rade su rfaces are treated i den ti call y.

B.

H eat fl ow paths can be u sed to fi nd the steady-state h eat loss to the g rou nd su rface.

C.

The exteri or ai r tem peratu re i s cri ti cal to determ i n i ng the heat loss.

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 2 20. When calculating daily temperatures, which of the following is the MOST important to take into consideration? A. daylight savings time B. local time C. solar time 21 . A new duct-mounted coil is inserted into an existing duct system with a total system airflow of 5,000 cfm (2.36 m³/s). The existing system is operating at a total static pressure of 1 .5” w.c. (373 Pa) and the additional coil will add 0.3” w.c. (74 Pa) to the total static pressure. The existing supply fan motor is operating at 1 236 RPM. What will the approximate resulting fan speed need to be to maintain the same total system airflow? A. 1 1 29 RPM B. 1 353 RPM C. 1 658 RPM 22. At diverging transitions of a fan/duct system, which of the following is correct? A. Absolute static pressure can decrease. B. Absolute total pressure increases. C. Velocity pressure decreases. 23. Evaporative heat loss from skin depends on: A. amount of moisture on the skin B. clothing area factor C. the surface area of the skin 24. When using equations for estimating heat transfer coefficient ( ℎ푐 ), the effective heat transfer area may be inaccurate for whom? A. seated and reclining persons with moving air B. standing persons in moving air C. walking and active persons in still air

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 2 25. What concept describes the proper ventilation rate averaging process.

CHECK ANSWERS CLEAR ANSWERS

A. active B. effective C. efficient 26. Flow devices with gradual contours are subject to separation that is more difficult to predict. Which of the following are used to reduce the loss in expansion? A. diffuser B. splitter C. stall 27. In metallic pipe when stress calculations are required, an area of concern is which of the following? A. external pressure stress B. lateral stress caused by pressure and weight C. stress from expansion and contraction 28. Using density to determine glycol concentration is unsatisfactory because: A. Density measurements are not temperature sensitive. B.

Inhibitor concentrations can change density.

C. Propylene glycol values exhibit a maximum at 50 to 55% concentration.

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DOMAIN 3

SECTION 3: DOMAIN 3, PROCEDURAL Overview

Domain 3 is focused on the procedures that HVAC designers execute. In this Domain, you deal with the practical considerations of taking your design from paper to reality. The Tasks in this Domain will test your abilities to: • Analyze your design, or another’s, for conformance with codes, standards, and regulations. • Review shop drawings to ensure that the materials to be installed meet the design intent. • Perform field reviews during construction and to verify/document as-built conditions. • Review and respond to requests for information (RFI) and other consultantcontractor interactions. The procedural work that Domain 3 concerns itself with is paramount to achieving the goals set out in Domain 1 and 2. As a designer, you do not just send your designs out into the ether, never to be heard from again. Carefully following proper procedures will allow your design to be built to your specifications. Once you are satisfied that you are sufficiently competent in all of the Tasks in Domain 3, move on to Domain 4.

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DOMAIN 3, TASKS A-K

Quick Quiz, Domain 3, Tasks A-K Now, let’s test your knowledge of some key terms/concepts found in Doma 3,

Tas ks

o p ti o n

A- K.

fro m

F o r e ach

th e

ch o i ce s

d e fi n i ti o n

o r co n ce p t,

s e l e ct

an d

wri te

in

th e

in

co rre ct

p ro vi d e d .

TERMS

DEFINITIONS

As - bu i l t

1 .

____________________ i s

o wn e r wh o C xA

th e

l e ad s ,

p l an s ,

co m m i s s i o n i n g

co m m i s s i o n i n g

an

e n ti ty

s ch e d u l e s ,

te am

to

i d e n ti fi e d

an d

i m pl e m e n t

by

th e

co o rd i n ate s

th e

p ro ce s s .

Faci l i ty g u i d e

2.

____________________ i s

a b as i c

bu i l d i n g

s ys te m s

I n ve s ti g ati o n d e s cri p ti o n

an d

M o n i to ri n g

p ro ce d u re s

Owner’s project

co n d i ti o n s ,

re q u i re m e n ts

to

p l an

co n fi rm e d

s e t p o i n ts ,

p ro ce d u re s

wi th

faci l i ty o pe rati n g

s ch e d u l e s ,

p ro p e rl y

g e n e ral

o p e rate

an d

th e

o pe rati n g

faci l i ty.

(OPR) 3.

Room

an d

o p e rati n g

cl e an l i n e s s

Com m i ssi on i n g

ce rti fi cate s

an d

a co m p l e te

d rawi n g s ,

pi pi n g ,

d o cu m e n ts

warran ti e s

sh ou l d

i n cl u d e

o f s ys te m

co m p l e ti o n

wi th

s e t o f ____________________

s u b m i tte d

p l u m bi n g ,

fro m

co n tro l ,

m e ch an i cal ,

an d

fi re

e l e ctri cal ,

p ro te cti o n

co n tracto rs .

4.

____________________ i s

a d o cu m e n t

th e

o f a p ro j e ct an d

fu n cti o n al

e xp e ctati o n s

5.

s ys te m

p aram e te rs

we e ks

be

u sed

In

th e

an d

u ses

o r d ata l o g g e rs

o ve r ti m e

an d

an al yz e

to

th e

fi n al

s ys te m

d ata d ays

co m m i s s i o n i n g

re p o rt,

or

if

re q u i re d ,

b u i l t re p o rt

co m p l e ti o n

m u s t be

o f te s ti n g

an d

d u ri n g

i n s tal l ati o n

a

p ro vi d i n g

ce rti fi e d

as -

of

d o cu m e n tati o n

i n cl u d e d .

____________________ p h as e

d e tai l e d

te s ti n g

bu i l d i n g

re co rd

th e

th e

o p e rate d .

____________________ i s

Th e

th at d e tai l s

l ate r.

co n s tru cti o n

7.

o f h o w i t wi l l

____________________ te s ti n g

au to m ati o n

6.

re q u i re m e n ts

i n te rvi e ws

an d

wi th

d o cu m e n tati o n

p e rfo rm an ce ,

an d

re co m m e n d e d

i n cl u d e s

m ai n te n an ce

o f e xi s ti n g

i d e n ti fi cati o n

an d

m o re

pe rs o n n e l ,

bu i l d i n g

an al ys i s

of

ch an g e s .

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CHECK ANSWERS

DOMAIN 3, TASKS A-K

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map after you have completed your Self-assessment of all four Domains. NOTE: This is the only set of Tasks for Domain 3. Answer the Practice Exam Questions that follow for Domain 3 before moving on to Domain 4. How confident are you in your knowledge, skills, and abilities in these job Tasks Task A: Analyze buildings, ❑ Confident building designs, or HVAC ❑ Somewhat plans for compliance with confident applicable codes, standards, and regulations. ❑ Not very confident

Task B: Apply Building Information Modeling (BIM) standards throughout drawing production.

❑ Confident ❑ Somewhat

Task C: Review shop drawings and equipment submittals for compliance with contract documents.

❑ Confident ❑ Somewhat

Task D: Interpret design documents during bidding/tender and construction phases.

❑ ❑

confident ❑ Not very confident

❑

❑

confident Not very confident Confident Somewhat confident Not very confident

Task-by-Task My Notes (Topics I Need to Spend Resource Guide time Studying) 201 7 Fundamentals Handbook, Chapter 40 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 52; 201 9 Applications Handbook, Chapters 44 and 66 201 7 Fundamentals Handbook, Chapter 1 9 Deep dive: 201 9 Applications Handbook, Chapters 41 and 60 201 9 Applications Handbook, Chapter 44 201 9 Applications Handbook, Chapter 44

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DOMAIN 3, TASKS A-K Task E: Review and comply with HVAC codes and standards.

❑ Confident 201 7 Fundamentals ❑ Somewhat Handbook, Chapter 40

Task F: Verify and document as-built field conditions for projects in construction.

❑ Confident ❑ Somewhat

Task G: Verify and document as-built field conditions for existing structures.

❑ ❑

Task H: Perform periodic field investigations (e.g., punch-lists, quality control, shop drawings).

❑ ❑

Task I: Perform review of Request for Information (RFI) and incorporate into bidding/tender documents.

❑ ❑

Task J: Prepare HVAC documentation for building permit application and coordinate with Authority Having Jurisdiction (AHJ).

❑ ❑

Task K: Incorporate field “as - bu i l t” d ocu m en ts i n to final documents.

❑ ❑

confident ❑ Not very confident

❑

❑

❑

❑

❑

❑

confident Not very confident Confident Somewhat confident Not very confident Confident Somewhat confident Not very confident Confident Somewhat confident Not very confident Confident Somewhat confident Not very confident Confident Somewhat confident Not very confident

Deep dive: 201 6 Systems and Equipment Handbook, Chapter 52; 201 9 Applications Handbook, Chapter 66 201 9 Applications Handbook, Chapter 44 201 9 Applications Handbook, Chapter 60 201 9 Applications Handbook, Chapter 44 201 9 Applications Handbook, Chapter 44 201 9 Applications Handbook, Chapter 44 201 9 Applications Handbook, Chapter 44

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DOMAIN 3

DOMAIN 3: PROCEDURAL PRACTICE EXAM QUESTIONS 1.

CHECK ANSWERS CLEAR ANSWERS

Whi ch of th e fol l owi n g i s devel oped wi th th e help of u sers, occu pan ts, an d owners?

2.

A.

basi s of desi g n (BOD)

B.

cu rren t faci li ty requ i rem ents (CFR)

C.

exi sti n g bu i ldi ng commissi oni ng (EBCx) process

What i s the bu i ldi n g desi g n and docu mentation m ethodol og y that rel i es on th e creati on and col lecti on of i nterrel ated, com pu tabl e i n form ati on abou t a bu i ldi ng proj ect th at i s a reliabl e, coordin ated, an d in tern al ly consi sten t dig ital representati on of the bu i l di ng ?

3.

4.

A.

bu i l di ng i n formati on man ag ement (BI M)

B.

bu i l di ng i n formati on m od el i n g (BI M)

C.

com pu ter-ai ded desi g n (CAD) systems

A system s man u al contai ns whi ch one of the fol lowi n g i tems? A.

cu rren t faci li ty requ i rem ents (CFR)

B.

desi g n cal cu l ati on s

C.

owner’s project requirements (OPR)

I n a si tu ati on of di spu tes or am bi g u i ti es, the h i g h est pri ori ty docu m en t to refer to i s whi ch of the fol lowi ng ? A.

contract

B.

project m an u al

C.

drawi n g s

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DOMAIN 3 5. A planned renovation of a 2,41 0 ft² (224 m²) retail space with a 40-occupant capacity is located on the second floor of a 5-story commercial building. Calculate the approximate minimum outdoor air requirement if the people outdoor air rate is 7.5 cfm/person (3.8 l/s-person) and the area outdoor air rate 0.1 8 cfm/ft² (o.9 l/s-m²). A. 489 cfm (230.8 l/s) B. 689 cfm (325.3 l/s) C. 734 cfm (353.6 l/s) 6. In conducting validations of the accuracy of the as-built plan for existing buildings, the FIRST step is to: A. check the air-distribution side B. identify equipment room locations C. verify the actual equipment versus previous submittals 7.

When the actual installation deviates from the issued “For Construction Plan,” what project document should be verified to reconcile? A. approved submittals B. meeting minutes C. specifications

8. During the project implementation process, which of the following is NOT a main responsibility of an HVAC designer? A.

monitor the HVAC contractor’s daily work

B. review and approve submittals C. validate Requests for Information (RFI) 9. Which of the following is a valid reason for a contractor to submit a Request for Information (RFI) during the construction process? A. The contractor failed to include a portion of the installation as part of their bid. B. There has been a field-directed change to the documents, and the contractor is requesting additional compensation. C. There is conflicting information between two (2) separate trades drawings.

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 3 1 0. A m ech ani cal permi t appl i cati on COMM ON LY requ i res wh i ch docu men t? A.

equ i pm ent warranty

B.

H VAC plans

C.

sh op drawi ng s

1 1 . As-bu i lt drawi n g s provi ded by the contractor serve whi ch of the fol lowi ng pu rposes? A.

al l ow the H VAC desi g ner to revi ew proposed su bsti tu ti ons pri or to i n stal l ati on

B.

docu men t ch ang es to the desi g n made throu g hou t constru cti on

C.

en su re that n o confl i cts exi st between all i nstal li ng contractors

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 4, TASKS A-J

SECTION 4.1 : DOMAIN 4, COORDINATION, TASKS A-J Overview

An HVAC designer does not exist in a vacuum. Your work affects, and is affected by, every system and assembly in the building. The Tasks in Domain 4 measure your ability to coordinate with other individuals or teams on the project and to ensure that your design meets the conditions you have been presented. These Tasks also allow you opportunities to provide input to the other design professionals as it relates to your systems. Tasks A-J will test your ability to: • Assist in the development of the basis of design (BOD) document with the other consultants and owner. • Coordinate space and structural requirements for your HVAC systems. • Analyze architectural documents to establish your design concept and calculations (Domain 1 & 2), as well as to provide input that may reduce overall energy usage and occupant comfort. • Collaborate with other team members on the HVAC design team. • Most importantly, collaborate with other design disciplines to ensure the health and safety of the building occupants. Design professionals from other disciplines may not be well versed in the requirements and constraints of your work. Your competency in this Domain will allow you to be an effective advocate for your design and to ensure that your design meets the requirements of the other disciplines.

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DOMAIN 4, TASKS A-J

Quick Quiz, Domain 4, Section 4.1 , Tasks A-J Now, let’s test your knowledge of some key

term s/con cepts fou n d i n D om ai n

4, Tasks A- J . For each d efi n i ti on or con cept, sel ect an d wri te i n th e correct opti on from th e ch oi ces provi d ed .

TERMS

DEFINITIONS

Basi s of d esi g n

1 .

____________________ i s u sed to resi st th e passag e of sm oke.

D esi g n param eters 2. D esi g n team

to eval u ate al l revi ew fi n d i n g s wi th th e

Owner’s project

____________________ an d see th at th e respon si bl e team m em ber i m pl em en ts th e approved d eci si on s.

req u i rem en t (OP R)

Perform an ce

I t i s th e respon si bi l i ty of th e own er or proj ect m an ag er

3.

Som e d esi g n revi ews u se ____________, g i vi n g 1 0 to 20% of th e d rawi n g s an d speci fi cati on s for an i n -

req u i rem en ts

d epth revi ew; i f on l y m i n i m al i ssu es are i d en ti fi ed , th e own er accepts th e su bm i ssi on .

Sam pl i n g

Sm oke d am per

4.

Th e ____________________ i s a d ocu m en t th at record s th e con cepts, cal cu l ati on s, d eci si on s, an d

Stru ctu ral en g i n eer

prod u ct sel ecti on s u sed to m eet th e OPR an d to sati sfy appl i cabl e reg u l atory req u i rem en ts, stan d ard s,

Ven ti l ati on

an d g u i d el i n es.

5.

Al l l oad s on th e stru ctu re sh ou l d be com m u n i cated to an d coord i n ated wi th th e ____________________.

6.

Th e ____________________ i s g en eral l y a set of con ci se obj ecti ve q u al i tati ve statem en ts, each wi th on e or m ore q u an ti tati ve perform an ce m etri cs or cri teri a.

7.

Captu re vel oci ty, d u ct m ateri al , an d perti n en t d u ct fi tti n g s an d fabri cati on are a few of th e ____________________ n ecessary for exh au st system s, especi al l y th ose servi n g fu m e exh au st, d u st, an d /or parti cl e col l ecti on to fu n cti on properl y, effi ci en tl y, an d per appl i cabl e cod es.

8.

____________________ an d pl u m bi n g d esi g n com e from th e d esi g n bu i l d i n g popu l ati on , an d are som ewh at i n d epen d en t of th e h i erarch y of on e system i n fl u en ci n g an oth er.

9.

Th e com m i ssi on i n g obj ecti ve focu ses on d ocu m en ted con fi rm ati on th at a faci l i ty fu l fi l l s th e speci fi ed __________________ for th e bu i l d i n g own er, occu pan ts, an d operators.

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CHECK ANSWERS

DOMAIN 4, TASKS A-J

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map after you have completed your Self-assessment of all four Domains. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task A: Assist in the ❑ Confident development of the basis of ❑ Somewhat design (BOD). confident ❑ Not very confident Task B: Review HVAC drawings with Commissioning Authority (CxA0).

❑ Confident ❑ Somewhat

Task C: Coordinate space requirements for HVAC equipment placement with other design team members.

❑ Confident ❑ Somewhat

Task D: Modify the HVAC design documents concept based on the outcome of the design team reviews.

❑ ❑

Task E: Coordinate systems expansion compensation design with structural engineer and piping vendor (e.g., thrust blocks, expansion joints, anchor points).

❑ ❑

confident ❑ Not very confident

❑

❑

❑

confident Not very confident Confident Somewhat confident Not very confident Confident Somewhat confident Not very confident

Task-by-Task Resource Guide 201 9 Applications Handbook, Chapters 44 and 60 Deep dive: 201 6 Systems and Equipment Handbook, Chapter 1 201 9 Applications Handbook, Chapter 44 Deep dive: 201 9 Applications Handbook, Chapter 60 201 9 Applications Handbook, Chapter 44

My Notes (Topics I Need to Spend time Studying)

201 9 Applications Handbook, Chapter 44 201 6 Systems and Equipment Handbook, Chapter 46 Deep dive: 201 9 Applications Handbook, Chapter 44

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DOMAIN 4, TASKS A-J Task F: Analyze architectural plans, sections, and elevations for use in HVAC design.

❑ Confident 201 9 Applications Chapters ❑ Somewhat Handbook, 44 and 45

Task G: Comply with client specifications and performance requirements to determine mechanical designs.

❑ Confident 201 9 Applications ❑ Somewhat Handbook, Chapter 44

Task H: Collaborate in the development of HVAC systems and design parameters.

❑ Confident 201 6 Systems and Handbook, ❑ Somewhat Equipment Chapters 1 and 50

Task I: Review architectural life safety plan relative to mechanical plan and apply fire and smoke damper requirements.

❑ Confident 201 9 Applications Chapters ❑ Somewhat Handbook, 44 and 54

❑

❑

❑

❑

confident Not very confident

Deep dive: 201 9 Applications Handbook, Chapter 60

confident Not very confident confident Not very confident

201 9 Applications Handbook, Chapter 44

confident Not very confident

Task J: Coordinate with life ❑ Confident 201 9 Applications and safety engineer to Chapters ❑ Somewhat Handbook, 44 and 54 design the smoke confident management and dive: 201 9 ❑ Not very Deep ventilation system per fire Applications confident code and regulation. Handbook, Chapter 60

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DOMAIN 4, TASKS K-U

SECTION 4.2: DOMAIN 4, COORDINATION, TASKS K-U Overview

As mentioned earlier, an HVAC designer does not exist in a vacuum, and you are, unfortunately, unable to design everything with which your systems need to interact. The equipment in your design requires electricity, water and drainage, structural support, and sound or vibration isolation. Typically, these are all achieved by different disciplines, and they require input from you to ensure that their work suits the needs of your design, and in many cases the reverse is also true. Often you are constrained by the power that is available to the building, or limitations of the existing structure will not support your equipment and distribution. Domain 4 is a measure of the human touch of design. Topics to be considered include the following: • Can you communicate appropriately with others and speak their language? • Can you consider other designers needs and convince them to give consideration to yours? While you may be very skilled in the Tasks of Domains 1 -3, they matter very little if you have insufficient power to your chiller because you did not articulate your needs to the electrical engineer. Likewise, no one will be particularly impressed with the accuracy of your calculations if the owner is now paying a small fortune for a structural change because you failed to properly coordinate your duct routing. As an HVAC designer, you are thoroughly involved from the very beginning, all the way to the end. While you may be part of a large team and focused only on a small portion of the design, your efforts and those of your team permeate throughout the entire project. The success of the project is a measure of your individual skill as a designer and your ability to interact with everyone else involved. Once you are satisfied that you are sufficiently competent in all of the Tasks in Domain 4, move on to the Study Map. ’

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DOMAIN 4, TASKS K-U

Quick Quiz, Domain 4, Section 4.2, Tasks K-U Now, l et’s test your knowledge of some key terms/concepts found in Domain 4, Tasks K-U. For each definition or concept, select and write in the correct option from the choices provided. TERMS

DEFINITIONS

Construction schedule

1 . ____________________ is a unit of real electrical power, equal to the power developed in a circuit by a current of 1 A flowing through a potential difference of 1 V.

Cycle Domestic water system Electrical designers Medium life to live Peer-to-peer Snubber Trade contractors UFAD zones Watt (W)

2. During the commissioning process evaluation, the commissioning authority should meet briefly with the owner; general, controls, mechanical, and electrical contractors; and mechanical and ____________________ to discuss the commissioning process. 3.

The CxA’s design review is not intended to replace

____________________ design reviews that check for accuracy and completeness of the design and calculations.

4. The ____________________ is the part of the fundamental waveform where the electrical potential goes from zero to a maximum to zero to a minimum, and back to zero again. 5. The acoustic characteristics of a room are considered to ____________________ if they have little sound absorption. 6. The CxA works with the contractors and construction manager to coordinate the commissioning schedule and ensure that commissioning activities are integrated into the master ____________________. 7. Approximate methods have been used by energy modelers, such as raising the thermostat set point in the ____________________ to represent a higher average air temperature or representing the actual zone with two stacked zones in the model. 8. During predesign and design, the list of areas to be commissioned may be general and include such options as electrical lighting controls, emergency power, and ____________________. 9. ____________________ of specialty or complex systems or designs should review commissioning requirements and performance criteria of their systems for coordination, schedule, and cost implications. 1 0. ____________________ is a device made of steel-housed resilient bushings arranged to prevent equipment from moving beyond an established gap.

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CHECK ANSWERS

DOMAIN 4, TASKS K-U

Self-assessment

What’s your baseline?

Read and consider each Task and rank your confidence level. Then consult the resources for each Task (especially those which you marked somewhat or not very confident). You might want to skim the resources on this first pass. Record notes in the last column about topics you need to spend additional time studying, marking chapters and page numbers where appropriate to guide you. You’ll use these notes to create your Study Map

after you have completed your Self-assessment of all four Domains. How confident are you in your knowledge, skills, and abilities in these job Tasks? Task K: Coordinate with ❑ Confident other design team ❑ Somewhat members during each confident design phase (e.g., ❑ Not very architects, structural confident designers, plumbing designers, electrical designers). Task L: Coordinate HVAC ❑ Confident implications for the building ❑ Somewhat electrical loads and confident electrical space mechanical requirements with electrical ❑ Not very confident design team members. Task M: Coordinate with structural engineer for HVAC requirements (e.g., duct and piping runs, anchorage, seismic bracing, sound isolation, support requirements, vibration). Task N: Coordinate with project design and construction schedules.

❑ Confident ❑ Somewhat confident ❑ Not very confident

Task-by-Task Resource Guide 201 9 Applications Handbook, Chapter 44

My Notes (Topics I Need to Spend time Studying)

201 9 Applications Handbook, Chapter 44 Deep dive: 201 9 Applications Handbook, Chapters 57 and 60 201 9 Applications Handbook, Chapters 44, 49, and 56 Deep dive: 201 9 Applications Handbook, Chapter 60

❑ Confident 201 9 Applications ❑ Somewhat Handbook, Chapter 44 confident ❑ Not very confident

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DOMAIN 4, TASKS K-U Task O: Coordinate electrical requirements for HVAC equipment.

❑ Confident 201 9 Applications Chapters ❑ Somewhat Handbook, 44 and 57

Task P: Coordinate requirements of HVAC system for domestic water and waste with plumbing designer.

❑ Confident ❑ Somewhat

Task Q: Coordinate with acoustical engineer for selection of ventilation equipment including sizing of ventilation distribution and air-handling equipment to meet designated sound pressure levels.

❑ ❑

Task R: Coordinate with energy modeler for HVAC system input.

❑ Confident ❑ Somewhat

Task S: Coordinate site piping and utility requirements with civil engineer.

❑ Confident ❑ Somewhat

Task T: Coordinate with vendors to prepare equipment schedules.

❑ ❑

Task U: Review drawings and identify potential obstructions that may impact the HVAC system (e.g., structural, fire proofing, lighting, sprinklers, walls).

❑ ❑

confident ❑ Not very confident

❑

❑

confident Not very confident Confident Somewhat confident Not very confident

confident ❑ Not very confident

❑

❑

❑

confident Not very confident Confident Somewhat confident Not very confident Confident Somewhat confident Not very confident

Deep dive: 201 9 Applications Handbook, Chapter 60 201 9 Applications Handbook, Chapter 44

201 9 Applications Handbook, Chapter 49 Deep dive: 201 7 Fundamentals Handbook, Chapters 3, 8, 9, 37; 201 9 Applications Handbook, Chapter 44 and 60 201 9 Applications Handbook, Chapter 44 Deep dive: 201 7 Fundamentals Handbook, Chapter 1 9; 201 9 Applications Handbook, Chapter 60 Deep dive: 201 9 Applications Handbook, Chapter 44 Deep dive: 201 9 Applications Handbook, Chapter 44 Deep dive: 201 9 Applications Handbook, Chapter 44

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DOMAIN 4

DOMAIN 4: COORDINATION PRACTICE EXAM QUESTIONS 1.

CHECK ANSWERS CLEAR ANSWERS

What i s the docu men t that records th e concepts, cal cu l ati ons, deci si on s,

and product selections used to meet the owner’s project requirements (OPR) ?

2.

A.

basi s of desig n (BOD)

B.

cu rren t faci li ty requ i rem ents (CFR)

C.

system s m an u al

When i s the M OST appropri ate ti me to beg i n th e com mi ssi oni ng process on a proj ect? A.

com mi ssi oni n g i s u n n ecessary i f the desi g ner has completed thei r work properly

B.

du ri n g th e predesi g n phase, when the scope and i n ten t h ave been establ i sh ed

C. 3.

when the project i s com pleted and perform ance n eeds to be veri fi ed

When coordi n ati n g wi th archi tectu ral m em bers of the desi g n team, what rel evant i n form ati on shou l d th e H VAC desi g n er provi de as i t rel ates to H VAC equ i pment placem ent?

4.

A.

equ i pm ent tonnag e

B.

power an d voltag e requ i rem ents

C.

servi ce cl earances an d cl earance to com bu sti bles

Whi ch of th e fol l owi n g statem ents appl i es to the rol e that the desi g n team plays i n th e commissi oning process? A.

I t i s the responsi bi lity of the owner or project m an ag er to evalu ate all revi ew fi ndi ng s wi th the desi g n team.

B.

Th e commi ssi oni ng professi onal i s u l ti m atel y respon si bl e for desi g n.

C.

Th e desi g n team makes recommendati ons to faci l i tate com mi ssi oni ng an d i m prove bu i l di ng performance.

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DOMAIN 4 5. Which expansion control system depends on slipping or sliding surfaces to accommodate movement and requires some type of seals or packing? A. ball joints B. expansion joints C. expansion loops 6. Which drawings should be analyzed FIRST prior to preparing duct or pipe routes for interferences and to ensure that all HVAC components fit in the available service spaces? A. architectural B. civil C. structural 7. When initiating the HVAC design process, to ensure a successful design, which documents should the HVAC designer refer to FIRST? A. applicable codes and standards B. ASHRAE handbooks C. client specifications and basis of design (BOD) 8. Which of the following design parameters are most likely to affect yearround energy usage when selecting direct-expansion (DX) coils? A. air-side

friction loss

B. enclosure sweat C. internal refrigerant pressure drop 9. When the duct layout for a proposed design is complete, the HVAC designer should check the ______ found in the _______ to ensure that the integrity of all fire-rated assemblies has been maintained. A. fire damper shop drawings; fire suppression drawings B. SMACNA standards; local fire code C. wall construction schedules; architectural drawings

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 4 1 0. The H VAC desi g n er shou l d coordi nate wi th wh i ch desi g n professi on al to ensu re that th e smoke m an ag em en t an d ven ti l ati on system meets rel evant fi re code? A.

ci vi l en g i neer

B.

el ectri cal en g i n eer

C.

l i fe safety eng i neer

1 1 . Constru cti on su bm i ttal s MOST often are: A.

presen ted to the con su l tant to rem ove all responsi bi li ty an d liabi li ty from th e contractor

B.

revi ewed by the desi g n team and the commi ssi oni ng ag ent to veri fy g eneral con form an ce wi th the desi g n intent

C.

a way to offl oad desi g n work from the con su l tan ts to the contractor

1 2. What type of proj ect deli very i s concerned wi th all aspects of bu i l di ng perform ance, bu t sti l l needs to coordi nate th e different bu i l di ng systems to avoi d rework. A.

i nteg rated

B.

n on com pou n d

C.

sequ enti al

1 3. I n the equ ati on for determ ini ng th e desi g n wi n d pressu re for lou vers,

푅ℎ ,

represen ts: A.

extern al pressu re coeffi ci ent at mean roof h ei g h t

B.

veloci ty pressu re at m ean roof heig ht

C.

volu m e of air fl ow at m ean roof heig ht

1 4. Whi ch of th e fol l owi n g i s a com m i ssi on i n g acti vi ty com pleted by the CxA? A.

bu dg et developm ent

B.

establ i sh ment of own er requ i rem ents

C.

su bm i ttal revi ews

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CHECK ANSWERS CLEAR ANSWERS

DOMAIN 4 1 5. The el ectri cian eng i n eer has provi ded th e H VAC desi g ner wi th a

CHECK ANSWERS CLEAR ANSWERS

m axi m u m power rati ng i n Kw for a parti cu l ar servi ce. Wh i ch formu l a wou l d be u sed to determ i ne the power con su m pti on of th e equ i pm ent? A.

am p = power x vol ts

B.

power = vol ts x amps

C.

power = vol ts / am ps

1 6. Wh en desi gn i n g a coolin g tower an d associ ated pi pi n g , what i n formati on sh ou l d th e H VAC desi g ner provi de to th e plu m bi ng desi g ner? A.

desi g n temperatu res

B.

m akeu p water requ i rem ents

C.

rate of heat rej ecti on and pu m p fl ow

1 7. I n Phase 2 of the I n teg rated Proj ect Deli very (I PD) process, what i s the rol e of th e H VAC desi g ner? A.

assist in assembling the owner’s project requirements (OPR)

B.

coordi nate servi ce requ i rements wi th el ectri cal desi g n team

C.

produ ce bu i l di n g l oad cal cu l ati ons

1 8. An H VAC desi g ner sh ou ld provi de whi ch i nform ati on to the bu i l di n g m odel er? A.

equ i pm ent stru ctu ral l oad

B.

l i teratu re abou t th e DOE-2 Alg ori thm

C.

U -factor for

fenestration

1 9. Wh at sh ou l d the H VAC desi g ner coordi nate wi th th e ci vi l eng i neer? A.

i ncom i ng spri nkler servi ce

B.

pi pi ng for a remote fl u i d cool er

C.

u n derg rou n d el ectri cal du ct

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DOMAIN 4 20. Having selected HVAC equipment with the assistance of the vendor, where is the BEST location for the relevant performance information?

CHECK ANSWERS CLEAR ANSWERS

A. equipment details B. equipment schedule C. equipment shop drawings 21 . Who is responsible for reviewing architectural, structural, plumbing, and electrical drawings for potential interference with the HVAC system? A. authority having jurisdiction (AHJ) B. HVAC designer C. mechanical contractor

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MY CHD CERTIFICATION EXAM STUDY MAP Task Notes Where should I focus my time when studying for the CHD exam? The tables that follow organize and record the Tasks and topics you need to focus upon as you prepare and study for the CHD exam (the responses you provided in the Domain review populated here). Add additional notes here as needed and use this to create a Study Plan which follows.

DOMAIN 1 : SYSTEM DESIGN

ADDITIONAL NOTES

Section 1 .1 , Tasks A-F Task A

Task B

Task C

Task D

Task E

Task F

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Section 1 .2, Tasks G-L Task G

Task H

Task I

Task J

Task K

Task L

Section 1 .3, Tasks M-R Task M

Task N

Task O

Task P

Task Q

Task R

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Section 1 .4, Tasks S-Z Task S

Task T

Task U

Task V

Task W

Task X

Task Y

Task Z(1 )

Task Z(2)

Task Z(3)

Task Z(4)

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DOMAIN 2: DESIGN CALCULATIONS

ADDITIONAL NOTES

Task A

Task B

Task C

Task D

Task E

Task F

Task G

Task H

Task I

Task J

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DOMAIN 3: PROCEDURAL

ADDITIONAL NOTES

Task A

Task B

Task C

Task D

Task E

Task F

Task G

Task H

Task I

Task J

Task K

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DOMAIN 4: COORDINATION

ADDITIONAL NOTES

Section 4.1 , Tasks A-J Task A

Task B

Task C

Task D

Task E

Task F

Task G

Task H

Task I

Task J

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Section 4.2, Tasks K-U Task K

Task L

Task M

Task N

Task O

Task P

Task Q

Task R

Task S

Task T

Task U

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Study Plan How do I plan my time leading up to my test date?

Now, take this time to map your study plan, week by week. We’ve suggested

a 6-week schedule here, which you can adjust up or down depending on when your exam is scheduled. For each week, note which Domain(s) and Task(s) you plan to focus on, taking into consideration the weight of each Domain (% of questions) and where you self-identified your gaps. For example, Domain 1 is 40% of the exam, and if you identified that you need to focus on studying 20 of the 29 Tasks, you may wish to break Domain 1 up

into several weeks of study. If you don’t know the exact date of your exam,

leave the dates blank; you can add that information in when you determine your test date.

STUDY CALENDAR

EXAM DATE:___________

Week 1 Dates: __________

Domain(s): ______________________ Task(s): ________________________ General Notes:

Week 2 Dates: __________

Domain(s): ______________________ Task(s): ________________________ General Notes:

Week 3 Dates: __________

Domain(s): ______________________ Task(s): ________________________ General Notes:

Week 4 Dates: __________

Domain(s): ______________________ Task(s): ________________________ General Notes:

Week 5 Dates: __________

Domain(s): _____________________ Task(s): _______________________ General Notes:

Week 6 Dates: __________

Domain(s): ________________________ Task(s): __________________________ General Notes:

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PRACTICE EXAM QUESTIONS: ANSWER KEY NOTE: In the following answers to the practice exam questions, the information in the parentheticals provide a location to the information related to the correct answer. Here is the key to use in order to decipher the information: Example: In Domain 1 , Question 1 below, if you wish to review the resource information (A-201 7/ch21 /p21 .23), you would review: A – the task being addressed 201 7 – the handbook in which the information is located Ch21 – the chapter in the handbook in which the information is located P21 .23 – the pages in the chapter of the handbook in which the information is located NOTE: There are certain answers that are not located in a handbook but are the result of job knowledge or industry practice.

Domain 1 : System Design 1 . (A-201 7/ch21 /p21 .23) A

1 5. (H-201 6/ch40/p40.1 ) C

2. (A-201 7/ch21 /p21 .23) B

1 6. (I-201 9/ch58/p58.1 ) A

3. (B-201 9/ch48/p48.20) C

1 7. (J-201 6/ch3/p3.7) B

4. (B-201 9/ch48/p48.4) C

1 8. (K-201 6/ch1 3/p1 3.23) B

5. (C-201 7/ch7/p7.1 9) C

1 9. (L-201 6/ch20/p20.6) C

6. (C-201 9/ch43/p43.3) B

20. (M-201 7/ch1 9/p1 9.3) B

7. (D-201 7/ch21 /p21 .1 5) A

21 . (M-201 7/Ch1 9/p1 9.1 ) B

8. (D-201 7/ch21 /p21 .1 6) C

22. (N-201 9/ch63/p63.2) A

9. (D-201 7/ch22/p22.1 ) A

23. (O-201 9/ch40/p40.7) A

1 0. (E-201 6/ch1 8/p1 8.1 ) B

24. (P-job knowledge) B

1 1 . (E-201 6/ch51 /p51 .2) A

25. (Q-201 6/ch4/p4.4) A

1 2. (F-201 6/Ch1 3/p1 3.1 2) B

26. (R-201 9/ch40/p40.3) B

1 3. (G-201 7/ch22/p22.8) A

27. (S-201 9/ch39/p39.1 7) C

1 4. (G-201 7/ch21 /p21 .20) B

28. (S-201 9/ch39/p39.1 7) C

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29. (T-201 6/ch44/p44.1 2) A

35. (X-201 6/ch32/p32.7) A

30. (U-201 7/ch21 /p21 .23) B

36. (Y-201 7/ch29/p29.9) A

31 . (U-201 7/ch22/p22.1 0) A

37. (Z1 -201 6/ch21 /p21 .9) A

32. (W-201 6/ch5/p5.8) A

38. (Z2-201 6/ch23/p23.5) C

33. (V-201 6/ch1 3/p1 3.4) B

39. (Z3-201 7/ch22/p22.2) C

34. (W-201 6/ch2/p2.8) C

40. (Z4-201 6/ch44/p44.3) A

Domain 2: Design Calculations 1 . (A-201 7/ch21 /p21 .1 8) B

1 6. (F-201 7/ch1 8/p1 8.1 6) C

2. (A-201 6/ch1 3/1 3.3) A

1 7. (F-201 7/ch1 4/p1 4.6) C

3. (E-201 6/ch44/p44.7) B

1 8. (G-201 7/ch1 8/p1 8.30) C

4. (A-201 7/ch36/p36.1 ) B

1 9. (G-201 7/ch1 8/p1 8.35) B

5. (B/job knowledge) B

20. (G-201 7/ch1 4/p1 4.1 2) B

6. (C-201 7/ch21 /p21 .1 9) C

21 . (H-201 6/ch21 /p21 .6) B

7. (C-201 7/ch21 /p21 .2) B

22. (H-201 7/ch21 /p21 .5) C

8. (C-201 7/ch22/p22.5) C

23. (I-201 7/ch9/p9.3) A

9. (D-201 7/ch3/p3.1 1 ) A

24. (I-201 7-ch9/p9.7) A

1 0. (D-201 7/ch9/p9.1 8) C

25. (I-201 7/ch1 6/p1 6.4) B

1 1 . (D-201 7/ch1 8/p1 8.2) B

26. (J-201 7/ch3/p3.5) A

1 2. (E-201 7/ch21 /p21 .1 6) A

27. (J-201 7/ch22/p22.8) C

1 3. (E-201 7/ch22/p22.5) A

28. (J-201 7/ch31 /p31 .1 2) B

1 4. (E-201 7/ch22/p22.1 0) B 1 5. (F-201 7/ch1 7/p1 7.1 1 ) B

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Domain 3: Procedural 1.

(A-201 9/ch44/p44. 1 3) B

7.

(G/I ndu stry practi ce) A

2.

(B-201 9/ch 41 /p44. 9-1 1 ) B

8.

(H /I n du stry practi ce) A

3.

(C-201 9/ch44/p44. 7) C

9.

(I /J ob kn owl edg e) C

4.

(D-job knowl edg e) A

1 0. (J /I n du stry practi ce) B

5.

(E-ASH RAE

1 1 . (K/I n du stry practi ce/j ob

61 . 1 /p1 6/calcu l ated) C 6.

kn owledg e) B

(F/I n du stry practi ce) C

Domain 4: Coordination 1.

(A-201 9/ch44/p44. 6) A

1 2. (L-201 9/ch60/p60. 9) A

2.

(B-201 9/ch44/p44. 7) B

1 3. (M-201 9/ch56/p56. 1 7) B

3.

(C/job knowl edg e) C

1 4. (N -201 9/ch44/p44. 8) C

4.

(D-201 9/ch44/p44. 7) A

1 5. (O-201 9/ch60/p60. 1 ) B

5.

(E-201 6/ch46/p46. 1 2) B

1 6. (P/J ob knowledg e) B

6.

(F/j ob kn owledg e) A

1 7. (Q-201 9/ch60/p60. 8) A

7.

(G /J ob kn owl edg e) C

1 8. (R-201 7/ch1 9/p1 9. 1 3) C

8.

(H -201 6/ch50/p50. 2) A

1 9. (S/J ob knowledg e) B

9.

(I /J ob kn owledg e) C

20. (T/J ob kn owl edg e) B

1 0. (J /J ob kn owl edg e) C

21 . (U /J ob knowledg e) B

1 1 . (K-201 9/ch44/p44. 8) B

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APPENDIX Common HVAC Design Formulas

REMEMBER: Words in blue/bold are defined in the glossary (and as popups).

1 ) Cooling & Heating Equations For SI: •

•

•

•

Sensible Heat H S = cp ρ q ∆T Latent Heat H L = c1 ρ q ∆W Total Heat H T = ρ q ∆h

Sensible Heat Ratio SHR = H S / H T

Where: HS = Sensible Heat (kW) HL = Latent Heat (kW) HT = Total Heat (kW) ∆T = Temperature Difference (°K) q = Air Volume Flow (m3/s) 3 ρ = Density of Air (1.202 kg/m ) cp = Specific Heat of Air (1.0 kJ/kg.K) c1 = Air Latent Factor (a typical value 3010) ∆W = Humidity Ratio Difference (kg water/kg dry air) ∆h = Enthalpy Difference (kJ/kg) SHR = Sensible Heat Ratio For I-P: •

•

Sensible Heat H S = 1 .085 × CFM × ∆T Latent Heat H L = 0.68 × CFM × ∆WGR

= 4840 × CFM × ∆WLB

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•

Total Heat H T = 4.5 × CFM × ∆h

•

Sensible Heat Ratio SHR = H S / H T

Where: HS = Sensible Heat (Btu/hr) HL = Latent Heat (Btu/hr) HT = Total Heat (Btu/hr) ∆T = Temperature Difference (°F) ∆WGR. = Humidity Ratio Difference (Gr.H2O/Lb.DA) ∆WLB. = Humidity Ratio Difference (Lb.H2O/Lb.DA) ∆h = Enthalpy Difference (Btu/Lb.DA) CFM = Air Flow Rate (Cubic Feet per Minute) SHR = Sensible Heat Ratio 2) Thermal Resistance R-Values/U-Values A. Thermal Value (R-Value) R=t/k B. Thermal Transmittance (U-Value) U = 1 / ΣR

Where: For SI:

k = Thermal Conductivity (W/(m·K)) R = Thermal Resistance ((m²·K)/W) U = Thermal Transmittance (W/(m²·K)) t = Thickness (m) ΣR = Sum of the Individual R-Values For I-P:

k = Thermal Conductivity (Btu./hr. ft. °F.) R = Thermal Resistance (hr. ft². °F./Btu.) U = Thermal Transmittance (Btu./hr. ft². °F.) t = Thickness (ft)

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3) Water System Equations For SI:

H = ρ ∙ q ∙ cp ∙ ∆T H q (Evap) = (ρ ∙ cp ∙ ∆T)

Where: H = Total Heat (kW) 3 q = Water Flow Rate (m /s) 3 ρ = Density of Water (997 kg/m ) cp = Specific Heat of Water (4.187 kJ/kg.K) ∆T = Temperature Difference (°K)

For I-P: H=

(GPM ∙ ∆T) 24

GPM (Evap) =

(H ∙ 24) ∆T

GPM (Cond) =

(H ∙ 30) ∆T

Where: H = Total Heat (Tons of Refrigerant) ∆T = Temperature Difference (°F) GPM = Water Flow Rate (Gallons per Minute) 퐺푄푀 (퐸푣푎푞) . = Evaporator Water Flow Rate (Gallons per Minute) 퐺푄푀 (퐶푝표푑) . = Condenser Water Flow Rate (Gallons per Minute) 4) Air Change Rate Equations For SI: ACH =

(q ∙ 3600) V

Where: ACH. = Air Change Rate3 per Hour q = Air Volume Flow (m3 /s) V = Space Volume (m )

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For I-P: ACH =

(CFM ∙ 60) V

Where: ACH. = Air Change Rate per Hour CFM = Air Volume Flow (cubic feet per minute) V = Space Volume (ft3) 5) Mixed Air Temperature Q Q TMA = (TRA ∙ ( RA ) ) + TO A ∙ ( O A ) QS A QSA

Where: For SI:

QSA= Supply Air (L/s) QRA = Return Air (L/s) QOA = Outside Air (L/s) TMA = Mixed Air Temperature (°C) TRA = Return Air Temperature (°C) TOA = Outside Air Temperature (°C) For I-P:

QSA= Supply Air (CFM) QRA = Return Air (CFM) QOA = Outside Air (CFM) TMA = Mixed Air Temperature (°F) TRA = Return Air Temperature (°F) TOA = Outside Air Temperature (°F) 6) Ductwork Equations •

Total Pressure

pt = ps + pv

Where: p t = Total Pressure (Pa) p s = Static Pressure (Pa) p v = Velocity Pressure (Pa) •

Velocity

V=

Q A

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Where: For SI:

V = Fluid Mean Velocity (m/s)3 Q = Volumetric Flow Rate (m /s) A = Cross-Sectional Area of Duct (m²) For I-P:

V = Fluid Mean Velocity (FPM) Q = Volumetric Flow Rate (CFM) A = Cross-Sectional Area of Duct (ft²) 7) Fan Affinity Laws A. Flow Rate B. Static Pressure

N Q1 = Q 2 ∙ ( 1 ) N2 P1 = P2 ∙ (

C. Electrical Power

Where:

N1 2 ) N2

W1 = W2 ∙ (

N1 3 ) N2

For SI:

Q = Volumetric Flow Rate (m³/s) N = Rotational Speed, Revolutions Per Minute (RPM) P = Static Pressure (Pa) W = Electrical Power (W) For I-P:

Q = Volumetric Flow Rate (CFM) N = Rotational Speed, Revolutions Per Minute (RPM) P = Static Pressure (in.wg) W = Electrical Power (W)

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8) Pump Affinity Laws (At Constant Pump Impeller Diameter) •

Flow Rate

•

Pump Head

N Q1 = Q 2 ∙ ( 1 ) N2 P1 = P2 ∙ (

•

Electrical Power

Where:

N1 2 ) N2

W1 = W2 ∙ (

N1 3 ) N2

For SI:

Q = Volumetric Flow Rate (m³/s) N = Rotational Speed, Revolutions Per Minute (RPM) P = Pump Head (bar) W = Electrical Power (W) For I-P:

Q = Volumetric Flow Rate (GPM) N = Rotational Speed, Revolutions Per Minute (RPM) P = Static Pressure (ft.wg) W = Electrical Power (W) 9) Pump Net Positive Suction Head (NPSH) Calculations • •

NPSH AVAIL > NPSH REQ’D Net Positive Suction Head Available: NPSH AVAIL = H A ± H S − H F − H VP

Where: For SI: NPSHAVAIL = Net Positive Suction Available at Pump (m) NPSHREQ’D = Net Positive Suction Required at Pump (m) HA = Pressure at Liquid Surface (m—10.2 m for Water at Atmospheric Pressure) HS = Height of Liquid Surface Above (+) or Below (−) Pump (m) HF = Friction Loss between Pump and Source (m) HVP = Absolute Pressure of Water Vapor at Liquid Temperature (m) For I-P:

NPSHAVAIL = Net Positive Suction Available at Pump (ft) NPSHREQ’D = Net Positive Suction Required at Pump (ft) HA = Pressure at Liquid Surface (ft—34 ft for Water at Atmospheric Pressure) HS = Height of Liquid Surface Above (+) or Below (−) Pump (ft) HF = Friction Loss between Pump and Source (ft) HVP = Absolute Pressure of Water Vapor at Liquid Temperature (ft) CERTIFICATION STUDY GUIDE | CERTIFIED HVAC DESIGNER (CHD)

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1 0) Cooling Tower Equations For SI: •

Cycles of Concentration C=

•

Blowdown B=

•

(E + D + B) (D + B)

E − ((C − 1 ) ∙ D) (C − 1 )

Evaporation E = 0.00 1 53 ∙ R ∙ m

•

Drift D = 0.0002 ∙ m

•

Range

R = EWT − LWT

Where: m = Circulating Cooling Water (m3/hr) B = Blowdown (m3/hr) C = Cycles of3 Concentration D = Drift (m /hr) 3 E = Evaporation (m /hr) EWT = Entering Water Temperature (°C.) LWT = Leaving Water Temperature (°C.) R = Range (°C.)

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For I-P: •

Cycles of Concentration C=

•

Blowdown B=

•

(E + D + B) (D + B)

E − ((C − 1 ) ∙ D) (C − 1 )

Evaporation E = GPM (Cond) ∙ R ∙ 0.00085

•

Drift D = 0.0002 ∙ GPM (Cond)

•

Range

R = EWT − LWT

Where: B = Blowdown (GPM) C = Cycles of Concentration D = Drift (GPM) E = Evaporation (GPM) EWT = Entering Water Temperature (°F.) LWT = Leaving Water Temperature (°F.) R = Range (°F.) 1 1 ) Efficiencies For SI: •

Coefficient of Performance (COP)

COP = •

To tal Cooling Capaci ty (W) Compre ss or Inpu t Power (W) + Conden s er Fan Inpu t Power (W)

Energy Efficiency Ratio (EER) EE R =

Ne t Cooling Capaci ty (W) ∙ 3.4 1 3 To tal Inpu t Power (W)

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For I-P: •

Coefficient of Performance (COP) COP =

•

To tal Cooling Capaci ty (BTU/h) (Compre ss or (W) + Conden s er Fan (W)) ∙ 3.4 1 3

Energy Efficiency Ratio (EER) EE R =

Ne t Cooling Capaci ty (BTU/h) To tal Inpu t Power (W)

1 2) Cooling Towers and Heat Exchangers • • •

APPROACH (COOLING TOWER) = LWT – AWB APPROACH (HEAT EXCHANGER) = EWTHS – LWTCS RANGE = EWT – LWT

Where:

For SI:

EWT = Entering Water Temperature (°C) LWT = Leaving Water Temperature (°C) AWB = Ambient Wet Bulb Temperature (°C) HS = Hot Side CS = Cold Side For I-P:

EWT = Entering Water Temperature (°F) LWT = Leaving Water Temperature (°F) AWB = Ambient Wet Bulb Temperature (°F) HS = Hot Side CS = Cold Side

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GLOSSARY ASHRAE Terminology is a comprehensive online glossary of more than 3700 terms and definitions related to the built environment, with a focus on HVAC&R, as well as building envelope, electrical, lighting, water and energy use, and measurement terms. Below are some key terms related to the HVAC designer job. Term Acceptable indoor air quality Air changes Airconditioning Air economizer Approach

Aspect ratio Basis of design (BOD)

Blowdown

Definition air in which there are no known contaminants at harmful concentrations as determined by cognizant authorities and with which a substantial majority (80% or more) of the people exposed do not express dissatisfaction expression of the amount of air movement or air leakage into or out of a building in terms of the number of building volumes or room volumes exchanged the process of treating air to meet the requirements of a conditioned space by controlling its temperature, humidity, cleanliness, and distribution a duct and damper arrangement and automatic control system that together allow a cooling system to supply outdoor air to reduce or eliminate the need for mechanical cooling during mild or cold weather (1 ) in a water cooling tower or evaporative cooling device, the difference between the average temperature of the circulating water leaving the device and the average wet-bulb temperature of the entering air. (2) in heat exchangers, the temperature difference between the leaving fluids (1 ) in any rectangular configuration, the ratio of the longer dimension to the shorter. (2) ratio of the length to width of a rectangular air duct a document that records the concepts, calculations, decisions, and product selections used to meet the o wner’s project requirements and to satisfy applicable regulatory requirements, standards, and guidelines; the document includes both narrative descriptions and lists of individual items that support the design process (1 ) discharge of water from a steam boiler or open recirculating system that contains high total dissolved solids; the addition of makeup water will reduce the concentration of dissolved solids to minimize their precipitation. (2) in pressure relief-devices, the difference between actuation pressure of a pressure relief valve and reseating pressure, expressed as a percentage of set pressure or in pressure units

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Breathing zone

the region within an occupied space between planes 3 and 72 in. (75 and 1 800 mm) above the floor and more than 2 ft (600 mm) from the walls or fixed air-conditioning equipment

Bypass factor

the percentage of the air that does not come into contact with the coil; the remaining air is assumed to exit the coil at the average coil temperature. See also apparatus dew point

Capacity

(1 ) measure of the maximum amount of energy or material that may be stored in a given system; See also nameplate rating; airconditioning capacity. (2) the rate of heat removal by the refrigerant used in the compressor or condensing unit in a refrigerating system. This rate equals the product of the refrigerant mass flow rate and the difference in the specific enthalpies of the refrigerant vapor at its thermodynamic state entering the compressor or condensing unit and refrigerant liquid at the thermodynamic state entering the mass flow control device. (3) the rate that heat is removed or added to a system. (4) maximum load for which a machine, apparatus, device, or system is designed or constructed

Cavitation

(1 ) formation by mechanical forces of vapor in liquids; specifically, the formation of vapor cavities in the interior or on the solid boundaries of liquids in motion, where the pressure is reduced to a critical value without a change in ambient temperature. (2) formation of cavities on a surface of a solid by liquid moving over it with velocity high enough to induce erosion of the surface when the cavity collapses. (3) in pumps, cavitation occurs when the pressure of the fluid is below the vapor pressure of the fluid at that temperature; cavitation has been described as having marbles or small stones inside the impeller casing. Cavitation over an extended period of time will erode the impeller and cause pump failure

Chill factor

the apparent temperature felt on exposed skin as a function of air temperature and wind speed. Chill factor is expressed in time (e.g., 1 1 seconds) to express how long it will take exposed skin to freeze. Compare to wind chill, which is expressed as a temperature

Coefficient of performance (COP)

(1 ) ratio of the rate of net heat output to the total energy input expressed in consistent units and under designated rating conditions. (2) ratio of the refrigerating capacity to the work absorbed by the compressor per unit time

Coefficient of performance (COP) – heat pump

the ratio of the rate of heat delivered to the rate of energy input, in consistent units, for a complete heat pump system, including the compressor and, if applicable, auxiliary heat, under designated operating conditions

Compression tank

pneumatic cushioning device, operating at system pressure, that absorbs fluid expansion as a result of temperature change and prevents unnecessary periodic operation of the relief valve. Compare to expansion tank

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Cooling design temperature Cooling design wetbulb temperature Cooling system energy coefficient of performance Daily range Degree day (Kelvin-day)

Dew-point temperature Direct digital control (DDC) Directexpansion (DX) refrigeration systems

Displacement ventilation system

the outdoor dry-bulb temperature equal to the temperature that is exceeded by 1 % of the number of hours during a typical weather year the outdoor wet-bulb temperature equal to the temperature that exceeds a stated number of hours during a typical weather year. The value is normally stated as a percent. This value is applicable to cooling systems where the main purpose is dehumidification and the prevention of mold and mildew a ratio calculated by dividing the net total cooling capacity in watts by the total power input in watts (excluding reheaters and humidifiers) at any given set of rating conditions. The net total cooling capacity is the total gross capacity minus the energy dissipated into the cooled space by the blower system difference between high and low temperatures for a typical day. Used in HVAC load calculations the difference in temperature between the outdoor mean temperature over a 24-hour period and a given base temperature, used in estimating heating and cooling energy use. For any one day, there are as many degree days (Kelvin-days) as there are degrees Fahrenheit (degrees Celsius) departure of the mean temperature for the day from the base temperature temperature of moist air saturated at pressure p, with the same humidity ratio W as that of the given sample of moist air. It is defined as the solution td(p, W) of the equation: Ws(p, td) = W a type of control where controlled and monitored analog or binary data (e.g., temperature, contact closures) are converted to digital format for manipulation and calculations by a digital computer or microprocessor, then converted back to analog or binary form to control physical devices (1 ) system in which the cooling effect is obtained directly from the expansion of the liquid refrigerant into a vapor. (2) common term applied to an air-conditioning or refrigeration system that utilizes the vapor-compression refrigeration cycle. In a vaporcompression refrigeration cycle, the refrigerant removes heat in the evaporator by directly expanding the entering liquid refrigerant into vapor as it leaves the evaporator. The vapor is then compressed and piped to a condenser where the heat removed by the evaporator and the heat of compression are rejected to another medium so that the gaseous refrigerant is condensed to a liquid. The liquid is then piped to a pressure reducing device/metering device to be supplied to the evaporator a type of air-distribution system, used only for cooling purposes, in which air at a temperature below room temperature is supplied to the floor level at a low discharge velocity [