Study Guide

Modern Plumbing, Part 1

Contents Contents

INSTRUCTION TO STUDENTS LESSON ASSIGNMENTS LESSON 1: FUNDAMENTALS OF PLUMBING, PART 1 LESSON 1—EXAMINATION LESSON 2: FUNDAMENTALS OF PLUMBING, PART 2 LESSON 2—EXAMINATION LESSON 3: WATER SUPPLY AND FIXTURES LESSON 3—EXAMINATION LESSON 4: FITTINGS, VALVES, AND HEATERS LESSON 4—EXAMINATION TEST YOUR KNOWLEDGE ANSWERS

1 5 7 49 55 67 73 81 85 95 99

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INTRODUCTION
This part of your program is based on the textbook, Modern Plumbing. It’s divided into 16 assignments; each assignment covers a specific area of the plumbing trade. The study material for this part of your program consists of 1. Your textbook, Modern Plumbing. It contains the assigned readings and review exercises at the end of each unit. These are assigned as self-check exercises. 2. This study guide, which contains the following features:
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Instructions Instructions

An assignment page that lists all of the reading assignments for your textbook Introductions to your lessons Listings of the self-check tests you should complete as part of each assignment Answers to the self-check exercises The examinations for each lesson

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As you now know, your textbook is covered by the reading assignments in this guide. Your textbook, Modern Plumbing, is the heart of this program. It’s very important that you read the material in the text and study it until you’re completely familiar with it. This is the material on which your examinations will be based. Each chapter begins with a list of learning objectives. Read through the learning objectives so that you’ll know what to expect when you read through the chapter. After you complete each chapter, you can use the list of learning objectives to review the important points of the chapter.

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A STUDY PLAN
We’ve divided the contents of your textbook, Modern Plumbing, into four lessons to aid your study. For each lesson, you’ll read part of the textbook. Then, you’ll complete an examination on the material you read for the lesson. The study guides contain a list of your lesson assignments, as well as the lesson examinations. Be sure to read all the material in both the textbook and the study guides before you attempt to complete your examinations. To get the most benefit out of each of your lessons, we suggest that you follow these steps: Step 1: In the study guide, read the introduction to Assignment 1. This is the first reading assignment of Lesson 1. Pay attention to the new ideas and concepts that are introduced, and carefully note the pages in your textbook where the reading assignment begins and ends. Skim the assigned pages in your textbook to get a general idea of their contents. Now, read the assigned pages in the textbook. Try to see the “big picture” of the material during this first reading. Next, go back and study the assigned pages in your textbook carefully. Pay careful attention to all details, including the illustrations, charts, and diagrams included in the textbook. Take notes on the important points and terms in a notebook, if you wish. At the end of the reading assignment, review what you’ve learned by completing the “Test Your Knowledge” questions in the textbook. Write out the answers on a separate piece of paper, if you wish. Try to answer the questions on your own without looking them up in the textbook. Don’t worry about making a mistake. The purpose of answering these questions is to review the material and to help you recognize the areas that you may need to study again. After you’ve

Step 2:

Step 3:

Step 4:

Step 5:

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Instructions to Students

answered the “Test Your Knowledge” questions, look up the answers in the back of your study guide to confirm that you answered the questions correctly. If you answered any questions incorrectly, review the material for that topic until you’re sure that you understand it. Note that the “Test Your Knowledge” questions are provided only for you to review your learning. You won’t be graded on the “Test Your Knowledge” questions in any way. Do not send your “Test Your Knowledge” answers to the school. Step 6: Repeat Steps 1 through 5 for each of the remaining reading assignments in the lesson. When you’ve finished reading all the assigned textbook pages for the lesson and you’re sure that you’re comfortable with the material, complete the examination for that lesson. Remember that the lesson examinations are contained in this study guide. Each examination contains a number of multiple-choice questions. Take your time as you complete the examination—there’s no time limit. You may go back to your textbook to review material at any time when you’re working on the examination. When you’re finished with each examination, submit only your answers to the school for grading. Submit your answers as soon as you complete the examination. Don’t wait until another examination is ready to send.

Step 7:

Instructions to Students

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Step 8:

Repeat these steps until all lessons have been completed. Remember, you may ask your instructor for help whenever you need it. Your instructor can answer your questions, provide additional information, and provide further explanation of your study materials. E-mail your questions to your instructor, and he or she will see to it that you receive the needed information. Your instructor’s guidance and suggestions will be very helpful as you progress through your program.

Now, look over the lesson assignments. Then, begin your study of Modern Plumbing with Lesson 1. Good luck with your program!

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Instructions to Students

Lesson 1: Fundamentals of Plumbing, Part 1

Assignments Assignments

For:

Read in the study guide: Pages 8–10 Pages 10–12 Pages 12–13 Pages 13–48

Read in the textbook: Pages 17–48 Pages 51–75 Pages 79–84 Pages 87–99 Material in Lesson 1

Assignment 1 Assignment 2 Assignment 3 Assignment 4

Examination 15184500

Lesson 2: Fundamentals of Plumbing, Part 2
For: Read in the study guide: Pages 56–57 Pages 58–60 Pages 60–61 Pages 61–62 Pages 62–63 Pages 64–65 Read in the textbook: Pages 103–109 Pages 111–126 Pages 129–135 Pages 137–142 Pages 145–152 Pages 155–165 Material in Lesson 2

Assignment 5 Assignment 6 Assignment 7 Assignment 8 Assignment 9 Assignment 10

Examination 15184600

Lesson 3: Water Supply and Fixtures
For: Read in the study guide: Pages 74–76 Pages 77–78 Pages 78–79 Read in the textbook: Pages 169–185 Pages 187–195 Pages 199–210 Material in Lesson 3

Assignment 11 Assignment 12 Assignment 13

Examination 15184700

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Lesson 4: Fittings, Valves, and Heaters
For: Read in the study guide: Pages 86–88 Pages 88–91 Pages 91–93 Read in the textbook: Pages 213–242 Pages 245–255 Pages 257–270 Material in Lesson 4

Assignment 14 Assignment 15 Assignment 16

Examination 15184800

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Lesson Assignments

Fundamentals of Plumbing, Part 1
The first lesson in your plumbing textbook describes the extensive list of equipment that helps protect your body while working in the plumbing trade. It also describes the proper methods for setting up and using ladders, scaffolds, and other tools of the plumbing trade. You’ll be introduced to the proper method of handling chemicals and interpreting the labels you’ll find on their containers. In the assignment devoted to tools, you’ll get a glimpse of the equipment used by plumbers. Layout, measuring, leveling, and marking tools help efficiently plan and execute a project while alignment tools help keep the installed components running straight and true. Plumbers employ cutting tools to alter the length of pipes and the structure itself, allowing pipes and components to pass through. Drills and boring equipment are covered extensively as they’re the primary means of getting the piping to where it needs to go. Perhaps the most important tools in a plumber’s toolbox are his or her wrenches. The array of available wrenches varies from adjustable models that adapt to a multitude of situations to single-purpose specialty wrenches that prove invaluable when performing tasks that might otherwise be nearly impossible. Finally, you’ll review some basic math skills while learning how plumbers apply these skills to measurement and other problems they encounter in everyday work. When you complete this lesson, you’ll be able to
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Lesson 1 Lesson 1

Explain the safe working habits that all plumbers must follow Identify and explain how to operate the tools used by plumbers Select the proper tool in the proper size for the desired task Explain the operation of the builder’s level and the laser level

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Read a rule accurately to the nearest 1/16 inch Compute pipe offsets, pipe slopes, and the volume and area of various objects Convert customary measure to metric measure

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ASSIGNMENT 1
Read this introduction to Assignment 1. Then, study Chapter 1, “Safety,” on pages 17–48 in the textbook, Modern Plumbing.

A professional plumber might define a successful project as one that’s completed within the proposed budget, completed in a timely fashion, and demonstrates quality workmanship. When listing what makes up a successful project, a plumber might not mention “following safe work practices.” However, the damages that eventually result from ignoring safe work practices will certainly have a negative effect on the project’s budget, quality, and completion time. Perhaps more important to the working plumber is the consequence of a serious injury, losing your job, or even losing your life. The work typically carried out by plumbers isn’t considered high risk when compared to many other construction-related jobs. However, at times the plumber finds him or herself in a less-than-ideal environment for completing this work. Plumbers must occasionally work in attics, basements, crawl spaces, and mechanical rooms. All of these spaces are designed to be accessible but aren’t typically habitable. This means they’re often unconditioned spaces with inadequate lighting, limited ventilation, and limited room to move. Without proper planning and layout of the workspace and preparation, such conditions can contribute to poor results, accidents, and long-term injuries. In an ideal world, all plumbing would be performed at eye level on a building’s first floor. Realistically there are times when plumbing work must be performed from ladders, scaffolds, and even rooftops. Choosing the correct equipment and understanding proper setup and limitations is critical for safe work above the floor.

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Modern Plumbing, Part 1

A safe work environment is one that’s safe for all those working in it. It’s not enough for you to take all precautions to make your workplace as safe as possible for you. It’s equally important that it be safe for others working, standing, or traveling around you. Likewise, others working in the area can affect your own safety. Be aware of what’s going on around you at all times, working safely while protecting yourself from the actions of others. Don’t take for granted that others have the same regard for safety as you. While reading this assignment in your textbook, it’s easy to accept the need to wear proper clothing, protective shoes, hard hats, gloves, and glasses. It makes sense to use fall restraints and keep an uncluttered work area. These are obvious precautions that help avoid obviously bad consequences. Not so obvious is the potential for injury to your body that results from small doses of damage over a long period of time. Lifting objects the wrong way may only result in a sore back at the end of the day. Over years, however, the result can be incapacitating. Hearing loss resulting from constant exposure to the noise of a construction site may occur so gradually that it’s unnoticed until much later in life. Dust and vapors that seem like nothing more than a mild irritation at the time of exposure can cause serious long-term damage to the lungs and other internal organs. All construction-related chemicals and most tools now have government-required labeling describing potential risks and proper handling. Eye and ear protection have evolved to be more efficient as well as comfortable to wear. Modern respirators and dust masks remove a broad range of particles and fumes while fitting much more comfortably than older models. At no time in the history of the plumbing trade has so much care gone into making sure your career as a plumber is a safe one. However, all the government-required safety labels, improved tool designs, and safety training can’t force you to work safely. Most experienced plumbers you’ll meet can relate at least one story about either damaging property, injuring themselves, or have causing injury to someone else by not practicing safe work habits. It should be your goal as a new plumber to thoroughly learn the material introduced in this assignment so you never have a similar story to tell.

Lesson 1

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After reading pages 17–48 in the textbook Modern Plumbing carefully and completing the “Test Your Knowledge” on pages 49, check your answers against those provided in the back of this study guide. (Note: You aren’t responsible for answering questions 2, 9, and 18.) When you’re sure you completely understand the material from Assignment 1, move on to Assignment 2.

ASSIGNMENT 2
Read this introduction to Assignment 2. Then, study Chapter 2, “Plumbing Tools,” on pages 51–75 in the textbook, Modern Plumbing.

Different construction trades require different levels of precision. Precision is the state of exactness and accuracy. For instance, tasks performed by a framing carpenter are often considered successful if they result in dimensions that measure an eighth of an inch or even a quarter of an inch from those called for on a print. Successful plumbing work, however, requires precision on the order of a sixteenth of an inch—two to four times the precision demanded in most framing work. Learning to properly read a fractional rule is critical to delivering the required level of precision. It may take some time to recognize the sixteenth tick marks on a rule. With practice you should learn to instantly see the measurement, much as you know the keys on a computer keyboard or the controls on the dashboard of a familiar vehicle. Often two or more workers must communicate measurements. The efficiency of a crew is dependant on how well each of them use the rule. An indication of poor measuring is a long pause between the whole number and the fractional part of the measurement whether calling it out to another worker or silently in your own mind. “Thirty two……..and………..eleven sixteenths” is an indication of counting tick marks rather than recognizing the measurement. Most of plumbing layout involves straight lines. Pipe runs can be perfectly vertical (plumb), or horizontal (level), or perpendicular (square), or even sloped as in a drain branch. Pipes are typically laid out in straight, horizontal, or vertical lines to

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Modern Plumbing, Part 1

simplify planning as well as speed installation and increase efficiency. Straight-line layout makes use of some very old tools like plumb bobs, chalk lines, squares, and bubble levels. A chalk line for instance, might be used to mark a series of holes to be drilled in a set of floor joists. A plumb bob allows you to position a plumbing fixture directly over a ceiling light fixture. New technologies incorporating lasers are available to enhance or even sometimes replace the older tools. However, while a bubble level might ensure a pipe is level over a long distance, a laser-leveling tool will fall short if line-of-sight obstructions exist along the pipe. There’s a wide array of tools used specifically for plumbing work—from rough-toothed pipe wrenches used when joining large-diameter metal pipes to delicate strap wrenches for installing chrome-plated pipes or other finely finished fixtures. Pipe cutters, pipe-threading tools, tubing benders, basin wrenches, and special vises are designed to accomplish specific plumbing tasks. In addition to tools designed specifically for plumbing work, you’ll need to acquire and learn to use many other power and hand tools. Structures aren’t constructed with passages for pipes. The plumber must alter the structure to get water from one point to another. Whether the structure is made of wood, concrete, or steel, holes must be drilled, snipped, chiseled, torched, or sawed. It’s important to know which tool will produce the correct result in the least amount of time. For every material in any given thickness, there’s a best choice to complete the task. Some tools like the reciprocating saw can handle many tasks with the simple choice of the most suitable blade. Other tools like the hammer drill, which punches holes in concrete, are dedicated to one specific material. This assignment and on-the-job experience will help you select the best tool for a job. Cutting, drilling, chiseling, and sawing wear on tools. Proper tool maintenance is just as important as proper tool selection. Maintenance tasks can be as simple as knowing when to discard a reciprocating saw’s blade or as complex as resharpening the teeth on a hole saw.

Lesson 1

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After reading pages 51–75 in the textbook Modern Plumbing carefully and completing the “Test Your Knowledge” on pages 76–77, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 2, move on to Assignment 3.

ASSIGNMENT 3
Read this introduction to Assignment 3. Then, study Chapter 3, “Leveling Instruments,” on pages 79–84 in the textbook, Modern Plumbing.

Square, plumb, and level are descriptive terms that apply to work done by all construction trades. In addition, plumbers must sometimes deal with sloped pipes, those whose elevation drops or rises over a given distance. You’ll use carpentry levels, squares, plumb bobs, steel tapes, and sometimes laser levels to install properly sloped pipes. However, working with sloped pipes requires that different techniques be employed while using these tools than those you’ll count on when installing vertical or horizontal ones. In the previous assignment, you were introduced to the method of using a laser-equipped bubble level to obtain a straight line (usually a level straight line). A builder’s level also produces a straight line but is typically used over a much longer distance. In the case of the laser, a light beam creates the straight line. The builder’s level relies on the precise position of crosshairs through the telescopic eyepiece to create a straight line of sight. In either case, the resulting straight line becomes a reference from which measurements (usually from the straight line down) are taken to ensure a pipe or trench is perfectly level or to determine the desired slope. The accuracy of the reference line is extremely dependent on proper setup of the leveling equipment. Modern laser levels are available with a self-leveling feature that speed this process.

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Modern Plumbing, Part 1

After reading pages 79–84 in the textbook Modern Plumbing carefully and completing the “Test Your Knowledge” on page 85, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 3, move on to Assignment 4.

ASSIGNMENT 4
Read this introduction to Assignment 4. Then, study Chapter 4, “Mathematics for Plumbers,” on pages 86–99 in the textbook, Modern Plumbing.

In the introduction to Assignment 2, you were reminded how important it is for a plumber to skillfully read a fractional rule. Beyond this skill, you’ll also need to calculate some lengths by adding or subtracting fractional measurements. Most of the math in this assignment may look familiar from your days in school, including the addition and subtraction of fractions expressed in sixteenths of an inch. One way to more quickly master these mathematical skills is to practice expressing all fractional measurements as whole numbers and sixteenths of an inch. For instance, 42 5/8 inches expressed as 42 10/16 or 3 1/4 inches as 3 4/16. Some crews actually avoid confusion by using this method of communicating measurements. It’s agreed among the workers that whatever follows the whole number call will be (in this case) a number of sixteenths. For instance you might hear “nine and fourteen,” which would be 9 7/8 or “one twenty two and two,” which would translate to 122 1/8 inches. Because fractional match is so important to a plumber’s work, and your textbook assumes that you can already perform basic math operations, this assignment introduction includes a brief review of basic math operations. It also includes example problems you can later refer to when solving more complex ones. Even if you feel your math skills are good, you should at least look over the example problems below before beginning your textbook reading assignment. However, if you have a lot of difficulty with math or feel that you need additional help, contact your instructor for assistance. He or she will answer your questions and may even send you additional materials to help sharpen your basic math skills.

Lesson 1

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As you’ve already learned, most pipes are laid out in straight lines, usually in vertical or horizontal directions (referred to as being plumb or level) and meeting in square joints or right angles. As you’re probably aware, the angle between two intersecting pipes can be measured in degrees, with a square or right angle measuring 90 degrees. When pipes meet at something other than 90 degrees, calculating pipe lengths becomes more complicated. Pipes must sometimes pass around obstructions or through tight spaces where 90-degree turns are unacceptable. In these cases, plumbers most often install 45-degree elbows. Less often, 22.5-, 30-, or 60-degree fittings are employed. This assignment introduces right-triangle calculations (specifically involving triangles with one 90-degree corner and two 45-degree corners) as a way to determine the length of pipe needed to connect two parallel pipes using 45-degree elbows. This slightly more complex calculation can sometimes be avoided with the use of a plumber’s rule, a unique tool that allows you to make direct measurements of components positioned at a 45-degree angle. Area and volume calculations are often important to a plumber. This assignment shows you how to determine the volume of tanks, containers, as well as fixtures like tubs and basins. At times it’s necessary to know the volume of a particular run of pipe. For instance, when a heating system’s boiler piping is exposed to freezing winter temperatures, the system must be protected with a sufficient concentration of antifreeze. Determining the concentration requires knowing the system’s total volume of water. Aside from draining the system and measuring the water drained, calculating the pipe run volume is the only way to know how much water it contains.

Adding and Subtracting Common Fractions
Now, let’s begin our review of basic plumbing math. We’ll briefly review some of the rules for the addition, subtraction, multiplication, and division of fractions and decimals. We’ll also review some example problems that illustrate how to work with measurements.

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Modern Plumbing, Part 1

As you know, whole numbers are numbers that have no fractional or decimal part, such as 5, 23, 98, or 1,240. In contrast, the numbers 1/2, 3 5/8, and 4.25 aren’t whole numbers. Your textbook assumes that you’re able to work with whole numbers, so the textbook’s basic math instruction begins with coverage of measurements and fractions. Making accurate measurements is an important part of a plumber’s job. Unfortunately, few measurements in the real world will ever turn out to be whole numbers. Instead, most measurements will include fractions. A fraction is a part of a whole unit. For example, a fraction of an inch is a part of one inch. If one inch were broken into four equal parts, each part would be one-fourth of an inch. The fraction one-fourth is written as 1/4. The number above the line in a written fraction is called the numerator, and the number below the line is called the denominator. As a plumber, you’ll work with fractions every day. For example, when you’re cutting lengths of pipe to different sizes, the sizes will rarely be whole numbers. To size pipe lengths correctly, you’ll need to be able to add and subtract fractions correctly. After completing this assignment, you’ll be able to work with fractions quickly and accurately. Most often, the fractions you’ll deal with in the building trades are fractions of one inch. These fractions of one inch are the common divisions on a ruler or tape measure. You’ll often work with fourths, eighths, and sixteenths of an inch. Since you’ll work with these fractions so often, you’ll quickly become comfortable with the addition and subtraction of these common fractions. Now, let’s look at some example problems that will help you review basic operations with fractions. We’ll start with some addition problems.

Lesson 1

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Example: Add the fractions 1/4 and 2/4. Solution: Because the denominators in the two fractions are the same, simply add the numerators. The denominator stays the same.
1 2 + =? 4 4 1 2 3 + = 4 4 4
Set up the problem.

Add the numerators (1 + 2 = 3). Answer: 3/4

Example: Add the fractions 3/16 and

13/ . 16

Solution: Because the denominators in the two fractions are the same, simply add the numerators. The denominator stays the same.
3 13 + =? 16 16 3 13 16 + = 16 16 16
16 =1 16
Set up the problem.

Add the numerators (3 + 13 = 16).

In this answer, the numerator and denominator of the fraction are the same. This means that the answer can be simplified to 1. Answer:
16/ , 16

or 1

Example: Add the fractions 1/2 and 1/4. Solution: When adding fractions, the denominators in both fractions must be the same. In this problem, 1/2 must be changed to an equivalent fraction with a denominator of 4.
1 1 + =? 2 4
1 2 1 1 = 2 2 2 2 = 2 4
Set up the problem.

Change 1/2 to an equal fraction with a denominator of 4. To do this, multiply both the numerator and denominator by 2. Now that both fractions have the same denominator (4), you can add the numerators (2 + 1 = 3). Answer: 3/4

2 4

1 3 = 4 4

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Modern Plumbing, Part 1

Example: Add the fractions 1/16 and 3/4. Solution: The denominators in both fractions must be the same. In this problem, 3/4 must be changed to an equivalent fraction with a denominator of 16.
1 3 + =? 16 4
3 4 4 3 = 4 4 4 12 = 4 16
Set up the problem.

Change 3/4 to an equal fraction with a denominator of 16. To do this, multiply both the numerator and denominator by 4. Both fractions now have the same denominator (16), so you can add the numerators (1 + 12 = 13). Answer: 13/16

1 12 13 + = 16 16 16

Example: Add the fractions 2/8 and 1/4. Solution: The denominators in both fractions must be the same. In this problem, 1/4 must be changed to an equivalent fraction with a denominator of 8.
2 1 + =? 8 4
Set up the problem.

1 4

2 1 = 2 4

2 2 = 2 8

Change 1/4 to an equal fraction with a denominator of 8. To do this, multiply both the numerator and denominator by 2. Both fractions now have the same denominator (8), so you can add the numerators (2 + 2 = 4). The answer can be reduced to a simpler form. To do this, divide both the numerator and denominator by 4. Answer: 4/8, or 1/2

2 2 4 + = 8 8 8
4 8 4 1 = 4 2

Fractions should always be represented in lowest terms, which means the simplest form. For example, the fractions 2/ and 8/ 1 4 16 would be equal to /2 in lowest terms. On the job site, fractional measurements should always be given in lowest terms to avoid mistakes and confusion.

Lesson 1

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Example: Add the fractions 3/4 and 5/8. Solution: The denominators in both fractions must be the same. In this problem, 3/4 must be changed to an equivalent fraction with a denominator of 8.
3 5 + =? 4 8
3 4 2 3 = 2 4 2 6 = 2 8
Set up the problem.

Change 3/4 to an equal fraction with a denominator of 8. To do this, multiply both the numerator and denominator by 2. Both fractions now have the same denominator (8), so you can add the numerators (6 + 5 = 11). In this answer, the numerator is larger than the denominator. This means that the fraction is equal to a number larger than 1. To reduce the answer to its simplest form, divide the numerator by the denominator (11 8 = 1 with a remainder of 3). The remainder goes in the numerator of the answer. The fraction 11/8 is equal to 1 3/8. Answer: 1 3/8

6 5 11 + = 8 8 8 11 = 11 8

8

11 8 = 1, with a remainder of 3
11 3 =1 8 8

In the previous problem, your answer was an improper fraction. In an improper fraction, the numerator is larger than the denominator. This means that the fraction is equal to a number larger than 1. In order to simplify the fraction 11/8, you divide the numerator by the denominator. When you divide 11 by 8, you get an answer of 1 with a remainder of 3. This means that the fraction 11/8 is equal to 1 whole (8/8) with 3/8 left over. Thus, the final answer is 1 3/8. Improper fractions should always be converted to a whole number and a proper fraction. Working on a job site, you should never use improper fractions when referring to measurements. Throughout your study of fractions, it will be useful to remember that the line in a fraction can always be read as “divided by.” That is, a fraction is equal to its numerator divided by its

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Modern Plumbing, Part 1

denominator. So, the fraction 1/2 can be read as 1 divided The fraction 3/16 can be read as “3 divided by 16.” This is true of every fraction. Now, let’s look at a few subtraction problems. Example: Subtract the fraction 1/4 from 2/4. Solution: Because the denominators in the two fractions are the same, simply subtract the numerators.
2 4 2 4 1 =? 4 1 1 = 4 4
Set up the problem.

Subtract the numerators (2 – 1 = 1). Answer: 1/4

Example: Subtract the fraction 3/16 from 7/16. Solution: Because the denominators in the two fractions are the same, simply subtract the numerators.
7 16 7 16 3 =? 16 3 4 = 16 16
Set up the problem.

Subtract the numerators (7 – 3 = 4).

4 16

4 1 = 4 4

The answer can be reduced to a simpler form. Divide both the numerator and denominator by 4. Answer: 1/4

Example: Subtract the fraction 1/4 from 1/2. Solution: When subtracting fractions, the denominators in both fractions must be the same. Change 1/2 to an equivalent fraction with a denominator of 4.
1 2
1 2 2 1 = 2 2

1 =? 4
2 2 = 2 4

Set up the problem.

Change 1/2 to an equal fraction with a denominator of 4. To do this, multiply both the numerator and denominator by 2.

Lesson 1

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2 4

1 1 = 4 4

Now that both fractions have the same denominator (4), you can subtract the numerators (2 – 1 = 1). Answer: 1/4
29/ . 32

Example: Subtract the fraction 5/8 from

Solution: When subtracting fractions, the denominators in both fractions must be the same. Change 5/8 to an equivalent fraction with a denominator of 32.
29 32
5 8 4 5 = 4 8

5 =? 8
4 20 = 4 32

Set up the problem.

Change 5/8 to an equal fraction with a denominator of 32. To do this, multiply both the numerator and denominator by 4. Now that both fractions have the same denominator (32), you can subtract the numerators (29 – 20 = 9). Answer: 9/32

29 32

20 9 = 32 32

Adding and Subtracting Mixed Numbers
The following example problems contain mixed numbers. A mixed number is a whole number and a fraction together, such as 1 1/2 or 5 3/8. When you add these numbers, simply add the fractions, and then add the whole numbers. Finally, if necessary, reduce the answer to its simplest terms. Example: Add the mixed numbers 10 1/4 and 3 2/4. Solution: Add the fractions first, and then the whole numbers.
10 1 2 +3 =? 4 4 1 2 3 + = 4 4 4
Set up the problem.

Add the fractions. The denominators in the two fractions are the same, so you can simply add the numerators (1 + 2 = 3). Add the whole numbers. Put the two parts of the answer (13 and 3/4) back together. Answer: 13 3/4

10 + 3 = 13
13 3 4

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Modern Plumbing, Part 1

Example: Add the mixed numbers 6 1/8 and 12 3/4. Solution: Add the fractions first, and then the whole numbers.
6
3 4

1 3 + 12 = ? 4 8
2 6 = 2 8

Set up the problem.

2 3 = 2 4

To add the fractions, you’ll need to change 3/4 to an equal fraction with a denominator of 8. To do this, multiply both the numerator and denominator by 2. Now you can add the numerators of the fractions (1 + 6 = 7).

1 8

6 7 = 8 8
6 + 12 = 18

Add the whole numbers. Put the two parts of the answer (18 and 7/8) back together. Answer: 18 7/8
10/ 16

18

7 8

Example: Add the mixed numbers 5

and 7 6/16.

Solution: Add the fractions first, and then the whole numbers.
5 10 6 +7 =? 16 16 10 6 16 + = 16 16 16 16 =1 16
Set up the problem.

Add the numerators of the fractions (10 + 6 = 16).

The numerator and denominator of the fraction are the same, so the fraction can be simplified to 1. Add the whole numbers. Put the two parts of the answer (12 and 1) back together. Because the fraction 16/16 was reduced to 1, there’s no longer a fraction part in this number. You can simply add the 1 to the 12 to get 13. Answer: 13

5 + 7 = 12 12 + 1 = 13

Lesson 1

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Subtraction problems that contain mixed numbers work exactly the same way as addition problems. Subtract the fractions first, and then the whole numbers. Example: Subtract the mixed number 2 1/4 from 8 3/4. Solution: Subtract the fractions first, and then the whole numbers.
8 3 4 3 4 2 1 =? 4
Set up the problem.

1 2 = 4 4

Subtract the fractions. The denominators in the two fractions are the same, so you can simply subtract the numerators (3 – 1 = 2). The fraction can be reduced to a simpler form. Divide both the numerator and denominator by 2. Subtract the whole numbers. Put the two parts of the answer (6 and 1/2) back together. Answer: 6 1/2

2 4

2 1 = 2 2

8–2=6
6 1 2

Example: Subtract the mixed number 4 3/8 from 10 1/2. Solution: Subtract the fractions first, and then the whole numbers.
10 1 2 4 3 =? 8
Set up the problem.

1 2

4 1 = 4 2

4 4 = 4 8

To subtract the fractions, you’ll need to change 1/2 to an equal fraction with a denominator of 8. To do this, multiply both the numerator and denominator by 4. Now you can subtract the numerators of the fractions (4 – 3 = 1).

4 8

3 1 = 8 8

10 – 4 = 6
6 1 8

Subtract the whole numbers. Put both parts of the answer (6 and 1/8) back together. Answer: 6 1/8

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Example: Subtract the mixed number 3 3/4 from 9 3/4. Solution: Subtract the fractions first, and then the whole numbers.
9 3 4 3 4 3 3 =? 4
Set up the problem.

3 =0 4

Subtract the numerators of the fractions (3 – 3 = 0). Because the subtraction of the fractions left you with 0, there will be no fraction part in the answer. Subtract the whole numbers. Answer: 6

9–3=6

Adding and Subtracting Measurements
Now, let’s look at some measurement problems. The measurements in the example problems contain both feet and inches. To add such measurements, add the feet first, and then the inches. Finally, simplify the answer as needed. Example: Add 2 feet 3 inches to 5 feet 4 inches. Solution: Add the feet and inches separately, then simplify the answer if necessary. 2 feet + 5 feet 2 feet + 5 feet 2 feet + 5 feet 7 feet 3 inches 4 inches 3 inches 4 inches 7 inches 3 inches 4 inches 7 inches
Set up the problem.

Add the inches first (3 inches + 4 inches = 7 inches).

Add the feet (2 feet + 5 feet = 7 feet). Answer: 7 feet 7 inches

Example: Add 4 feet 2 1/4 inches to 6 feet 8 2/4 inches. Solution: Add the feet and inches separately, then simplify the answer if necessary. 4 feet 2 1/4 inches + 6 feet 8 2/4 inches
Set up the problem.

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23

4 feet 2 1/4 inches + 6 feet 8 2/4 inches 10 3/4 inches 4 feet 2 1/4 inches + 6 feet 8 2/4 inches 10 feet 10 3/4 inches

Add the inches first (2 1/4 inches + 8 2/4 inches = 10 3/4 inches). Add the feet (4 feet + 6 feet = 10 feet). Answer: 10 feet 10 3/4 inches

Example: Add 1 foot 9 inches to 3 feet 81/2 inches. Solution: Add the feet and inches separately, then simplify the answer if necessary. 1 foot 9 inches 1/ inches + 3 feet 8 2 1 foot 9 inches + 3 feet 8 1/2 inches 17 1/2 inches 1 foot 9 inches + 3 feet 8 1/2 inches 4 feet 17 1/2 inches 17 1/2 inches = 1 foot 5 1/2 inches
Set up the problem.

Add the inches first (9 inches + 8 1/2 inches = 17 1/2 inches). Add the feet (1 foot + 3 feet = 4 feet).

The answer can be simplified. Because the measurement 17 1/2 inches is greater than 1 foot, it should be simplified to feet and inches. You know that 12 inches equals 1 foot, so 17 1/2 inches must equal 1 foot 5 1/2 inches. Add 1 foot 5 1/2 inches to the 4 feet you already had in the answer. Answer: 5 feet 5 1/2 inches

4 feet + 1 foot 5 1/2 inches 5 feet 5 1/2 inches

Now, let’s look at some subtraction examples. Example: Subtract 1 foot 5 inches from 3 feet 8 inches. Solution: Subtract the feet and inches separately, then simplify the answer if necessary. 3 feet – 1 foot 3 feet – 1 foot 8 inches 5 inches 8 inches 5 inches 3 inches
Set up the problem.

Subtract the inches first (8 inches – 5 inches = 3 inches).

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3 feet – 1 foot 2 feet

8 inches 5 inches 3 inches

Subtract the feet (3 feet – 1 foot = 2 feet). Answer: 2 feet 3 inches

Example: Subtract 6 feet 5 1/8 inches from 10 feet 9 3/8 inches. Solution: Subtract the feet and inches separately, then simplify the answer if necessary. 10 feet – 6 feet 10 feet – 6 feet 9 3/8 inches 5 1/8 inches 9 3/8 inches 5 1/8 inches 4 2/8 inches
2 8 2 1 = 2 4
Set up the problem.

Subtract the inches first (9 3/8 inches – 5 1/8 inches = 4 2/8 inches). Reduce the fraction 2/8 to its simplest form. To do this, divide both the numerator and denominator by 2. Subtract the feet (10 feet – 6 feet = 4 feet). Answer: 4 feet 4 1/4 inches

10 feet – 6 feet 4 feet

9 3/8 inches 5 1/8 inches 4 1/4 inches

Example: Subtract 3 feet 9 inches from 7 feet 6 1/4 inches. Solution: Subtract the feet and inches separately, then simplify the answer if necessary. Note that in order to subtract in this problem, you’ll need to “borrow” 12 inches from the 7 feet and add them to the 6 1/4 inches. 7 feet 6 1/4 inches – 3 feet 9 inches
Set up the problem. Because 9 inches is greater than 6 1/4 inches, you’ll need to “borrow” to subtract in this problem. Borrow 12 inches from the 7 feet. This changes the measurement of 7 feet to 6 feet 12 inches. Add the borrowed 12 inches to the 6 1/4 inches. Thus, the measurement 7 feet 6 1/4 inches changes to 6 feet 18 1/4 inches. Rewrite the problem to reflect the “borrow” you made.

7 feet = 6 feet 12 inches

6 feet 12 inches 1/ inches + 6 4 6 feet 18 1/4 inches 6 feet 18 1/4 inches – 3 feet 9 inches

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25

6 feet 18 1/4 inches – 3 feet 9 inches 1/ inches 9 4 6 feet 18 1/4 inches – 3 feet 9 inches 3 feet 9 1/4 inches

Subtract the inches first (18 1/4 inches – 9 inches = 9 1/4 inches). Subtract the feet (6 feet – 3 feet = 3 feet). Answer: 3 feet 9 1/4 inches

Example: Subtract 1 foot 11 3/16 inches from 4 feet 1 1/8 inches. Solution: Subtract the feet and inches separately, then simplify the answer if necessary. Note that to subtract in this problem, you’ll need to borrow twice. 4 feet 1 1/8 inches – 1 foot 11 3/16 inches
1 8 2 1 = 2 8 2 2 = 2 16
Set up the problem.

First, change 1/8 to an equal fraction with a denominator of 16. To do this, multiply both the numerator and denominator by 2. Rewrite the problem with the 2/16 in its proper place. Then, note that because 3/16 is greater than 2/16, you’ll need to borrow.

4 feet 1 2/16 inches – 1 foot 11 3/16 inches

1 inch = 16/16 inch 16/ 2 18/ 16 + /16 = 16 2/ 4 feet 1 16 inches = 4 feet 18/16 inches

Borrow 1 inch from the 4 feet 1 inch. Change the 1 inch to 16/ 16 inch. Then, add the borrowed 16/ 2 16 to /16 inch. This changes the measurement 4 feet 1 2/16 inches to 4 feet 18/16 inches. Rewrite the problem again with the 18/16 in its proper place. Because 11 3/16 inches is greater than 18/16 inches, you’ll need to borrow again.

4 feet 18/16 inches – 1 foot 11 3/16 inches

1 foot = 12 inches 12 inches + 18/16 = 12 18/16 inches 4 feet 18/16 inches = 3 feet 12 18/16 inches 3 feet 12 – 1 foot 11
18/ 16 inches 3/ 16 inches

Borrow 1 foot from the 4 feet. Change the 1 foot to 12 inches. This changes the measurement 4 feet 18/16 inches to 3 feet 12 18/16 inches. Rewrite the problem again to reflect the borrow you made.

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3 feet – 1 foot

12 18/16 inches 11 3/16 inches 15/ 16 inches 12 18/16 inches 11 3/16 inches 1 15/16 inches 12 18/16 inches 11 3/16 inches 1 15/16 inches

Subtract the fractions first (18/16 inches – 3/16 inches =
15/ 16

inches).

3 feet – 1 foot

Subtract the inches (12 inches – 11 inches = 1 inch).

3 feet – 1 foot 2 feet

Subtract the feet (3 inches – 1 foot = 2 feet). Answer: 2 feet 1
15/ 16

inches

Multiplying Common Fractions
Now, let’s review the multiplication of fractions. The procedure for multiplying common fractions is very simple. All you have to do is multiply the numerators together, multiply the denominators together, and then reduce the answer to its lowest terms. Example: Multiply the fraction 5/8 by 3/8. Solution: Multiply the numerators together, multiply the denominators together, and reduce the answer to lowest terms, if necessary.
5 8 5 8 5 8 3 =? 8 3 15 = 8 ? 3 15 = 8 64
Set up the problem.

Multiply the numerators together (5 3 = 15).

Multiply the denominators together (8 8 = 64). Answer: 15/64

Example: Multiply the fraction 2/8 by 2/4. Solution: Multiply the numerators together, multiply the denominators together, and reduce the answer to lowest terms, if necessary.
2 8 2 =? 4
Set up the problem.

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27

2 8

2 4 = 4 ?

Multiply the numerators together (2 2 = 4).

2 8

2 4 = 4 32

Multiply the denominators together (8 4 = 32).

4 32

4 1 = 4 8

The answer can be reduced. Divide both the numerator and the denominator by 4. Answer: 1/8

Multiplying Fractions by Whole Numbers or Mixed Numbers
To multiply a fraction by a whole number, you’ll need to convert the whole number to a fraction. To do this, simply write the whole number in the numerator and the number 1 in the denominator. Using this process, the whole number 3 would be equal to 3/1, the whole number 10 would be equal to 10/1, the whole number 25 would be equal to 25/1, and so on. Example: Multiply the fraction 3/16 by the whole number 4. Solution: Change the whole number to a fraction, and then multiply the two fractions together.
4 4 1
Change the whole number 4 to the fraction 4/1.

3 16 3 16 3 16

4 =? 1 4 12 = 1 4 12 = 1 16

Set up the problem.

Multiply the numerators together (3 4 = 12).

Multiply the denominators together (16 1 = 16).

12 16

4 3 = 4 4

The answer can be reduced to a simpler form. Divide both the numerator and the denominator by 4. Answer: 3/4

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Example: Multiply the whole number 10 by the fraction 7/8. Solution: Change the whole number to a fraction, and then multiply the two fractions together.
10 10 1
Change the whole number 10 to the fraction 10/1.

10 1 10 1 10 1

7 =? 8 7 70 = 8 7 70 = 8 8

Set up the problem.

Multiply the numerators together (10 7 = 70).

Multiply the denominators together (1 8 = 8).

70 = 70 8

8

70 8 = 8, with a remainder of 6

In this answer, the numerator is larger than the denominator. To reduce the answer to its simplest form, divide the numerator by the denominator (70 8 = 8 with a remainder of 6). The remainder goes in the numerator of the answer. The fraction 70/8 is equal to 8 6/8.

70 6 =8 8 8

6 8

2 3 = 2 4

Note that the fraction 6/8 can be reduced to a simpler form. Divide both the numerator and denominator by 2. Answer: 8 3/4

To multiply a fraction by a mixed number, you’ll need to change the mixed number into an improper fraction before multiplying. Converting a mixed number to an improper fraction isn’t difficult. Remember that a mixed number is a whole number and a fraction together, such as 2 1/4. To change a mixed number to an improper fraction, multiply the denominator of the fraction times the whole number, add the result

Lesson 1

29

to the numerator of the fraction, and place that result over the denominator of the fraction. So, to convert the mixed number 2 1/4 to an improper fraction, follow these steps:
2 1 4
Multiply the denominator of the fraction (4) times the whole number (2). The result is 8.

4

2=8
Add the result (8) to the numerator of the fraction (1). Place the result (9) over the denominator of the fraction (4). Answer: The mixed number 2 1/4 is equal to the improper fraction 9/ . 4

8+1=9

9 4

Now, suppose you need to convert the mixed number 4 3/8 to an improper fraction. Follow these steps:
4 3 8
Multiply the denominator of the fraction (8) times the whole number (4). The result is 32.

8

4 = 32
Add the result (32) to the numerator of the fraction (3). Place the result (35) over the denominator of the fraction (8). Answer: The mixed number 4 3/8 is equal to the improper fraction 35/ . 8
13/ 16

32 + 3 = 35

35 8

Let’s do one more example. Convert 1 fraction. Follow these steps:
13 1 16

to an improper

Multiply the denominator of the fraction (16) times the whole number (1). The result is 16.

16

1 = 16
Add the result (16) to the numerator of the fraction (13). Place the result (29) over the denominator of the fraction (16). Answer: The mixed number 1 13/16 is equal to the improper fraction 29/16.

16 + 13 = 29

29 16

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Now, let’s try a few multiplication problems that contain mixed numbers. Example: Multiply the fraction 7/16 by the mixed number 2 3/4. Solution: Change the mixed number to an improper fraction, then multiply the two fractions together.
2 7 16 7 16 7 16 3 11 = 4 4 11 =? 4 11 77 = 4 ? 11 77 = 4 64
Change the mixed number 2 3/4 to the improper fraction 11/4. Set up the problem.

Multiply the numerators together (7 11 = 77).

Multiply the denominators together (16 4 = 64).

77 = 77 64

64

77 64 = 1, with a remainder of 13
77 13 =1 64 64
In this answer, the numerator is larger than the denominator. To reduce the answer to its simplest form, divide the numerator by the denominator (77 64 = 1 with a remainder of 13). The remainder goes in the numerator of the answer. The fraction 77/64 is equal to 1 13/64. Answer: 1 13/64

Example: Multiply the mixed number 1 3/4 by the mixed number 5 5/8. Solution: Change the mixed numbers to improper fractions, then multiply the two fractions together.
3 7 1 = 4 4 5 45 5 = 8 8
Change the mixed number 1 3/4 to the improper fraction 7/4.

Change the mixed number 5 5/8 to the improper fraction 45/8.

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7 4 7 4 7 4

45 =? 8 45 315 = 8 ? 45 315 = 32 8

Set up the problem.

Multiply the numerators together (7 45 = 315).

Multiply the denominators together (4 8 = 32).

315 = 315 32

32

315 32 = 9, with a remainder of 27
315 27 =9 32 32

In this answer, the numerator is larger than the denominator. To reduce the answer to its simplest form, divide the numerator by the denominator (315 32 = 9 with a remainder of 27). The remainder goes in the numerator of the answer. The fraction 315/32 is equal to 9 9 27/32
27/ . 32

Answer:

Example: Multiply the mixed number 1 2/4 by the whole number 7. Solution: Change the mixed number to an improper fraction, change the whole number to a fraction, and then multiply the two fractions together.
1 2 6 = 4 4 7 1
Change the mixed number 1 2/4 to the improper fraction 6/4. Change the whole number 7 to the fraction 7/1. Set up the problem.

7=

6 4 6 4 6 4

7 =? 1 7 42 = 1 ? 7 42 = 1 4

Multiply the numerators together (6 7 = 42).

Multiply the denominators together (4 1 = 4).

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42 = 42 4

42

4 = 10, with a remainder of 2

4
To reduce the answer to its simplest form, divide the numerator by the denominator (42 4 = 10 with a remainder of 2). The remainder goes in the numerator of the answer. The fraction 42/4 is equal to 10 2/4. Note that the fraction 2/4 can be reduced to a simpler form. Divide both the numerator and denominator by 2. Answer: 10 1/2

42 2 = 10 4 4

2 4

2 1 = 2 2

Dividing Fractions
Dividing fractions is exactly the same as multiplying fractions, but with one little twist added. To divide one fraction by another, you must first turn the fraction you’re dividing by upside down. Then, change the division sign to a multiplication sign, and complete the problem. This may sound complicated at first, but it’s actually very easy. Let’s look at a few example problems. Example: Divide 1/2 by 3/4. Solution: Turn the fraction you’re dividing by upside down, then multiply the two fractions.
1 2 1 2 3 =? 4 4 3
Set up the problem.

3 1 = 4 2 1 2 1 2

You’re dividing by 3/4, so turn 3/4 upside down. Change the division sign to a multiplication sign. Multiply the fractions together. Multiply the numerators first (1 4 = 4). Multiply the denominators (2 3 = 6).

4 4 = 3 ? 4 4 = 3 6

4 6

2 2 = 2 3

The answer can be reduced to a simpler form. Divide the numerator and the denominator by 2. Answer: 2/3

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33

Example: Divide 7/16 by 1/8. Solution: Turn the fraction you’re dividing by upside down, then multiply the two fractions.
7 16 7 16 1 =? 8 8 1
Set up the problem.

1 7 = 8 16 7 16 7 16

You’re dividing by 1/8, so turn 1/8 upside down. Change the division sign to a multiplication sign. Multiply the fractions together. Multiply the numerators first (7 8 = 56). Multiply the denominators (16 1 = 16).

8 56 = 1 ? 8 56 = 1 16

56 = 56 16

16

56 16 = 3, with a remainder of 8
56 8 =3 16 16

To reduce the answer to its simplest form, divide the numerator by the denominator (56 16 = 3 with a remainder of 8). The remainder goes in the numerator of the answer. The fraction 56/16 is equal to 3 8/16. Note that the fraction 8/16 can be reduced to a simpler form. Divide both the numerator and denominator by 8. Answer: 3 1/2

8 16

8 1 = 8 2

Example: Divide 3/4 by 3. Solution: Turn the fraction you’re dividing by upside down, then multiply the two fractions.
3 4
Set up the problem.

3=? 3 1 1 3
Change the whole number 3 to 3/1.

3=

3 4

3 3 = 1 4

You’re dividing by 3/1, so turn 3/1 upside down. Change the division sign to a multiplication sign.

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3 4 3 4
3 12

1 3 = 3 ? 1 3 = 3 12
1 3 = 3 4

Multiply the fractions together. Multiply the numerators first (3 1 = 3). Multiply the denominators (4 3 = 12).

The answer can be reduced to a simpler form. Divide the numerator and the denominator by 3. Answer: 1/4

Example: Divide 2 3/8 by 5/8. Solution: Change the mixed number to an improper fraction. Turn the fraction you’re dividing by upside down, then multiply the two fractions.
2 3 8 5 =? 8 3 19 2 = 8 8 19 8 19 8 19 8 5 19 = 8 8 8 5
Set up the problem.

Change the mixed number 2 3/8 to the improper fraction 19/8.

You’re dividing by 5/8, so turn 5/8 upside down. Change the division sign to a multiplication sign. Multiply the fractions together. Multiply the numerators first (19 8 = 152). Multiply the denominators (8 5 = 40).

8 152 = 5 ? 8 152 = 5 40

152 = 152 40

40

152 40 = 3, with a remainder of 32
152 32 =3 40 40

To reduce the answer to its simplest form, divide the numerator by the denominator (152 40 = 3 with a remainder of 32). The remainder goes in the numerator of the answer. The fraction 152/40 is equal to 3 32/40.

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35

32 40

8 4 = 8 5

Note that the fraction 32/40 can be reduced to a simpler form. Divide both the numerator and denominator by 8. Answer: 3 4/5

Example: Divide 2 1/4 by 1 1/8. Solution: Change the mixed numbers to improper fractions. Turn the fraction you’re dividing by upside down, then multiply the two fractions.
2 1 4 1 1 =? 8 9 4 9 8 8 9
Set up the problem.

1 2 4 1 1 8 9 4 9 9 = 8 4 9 4 9 4

Change the mixed number 2 1/4 to the improper fraction .

Change the mixed number 1 1/8 to the improper fraction 9/8.

You’re dividing by 9/8, so turn 9/8 upside down. Change the division sign to a multiplication sign. Multiply the fractions together. Multiply the numerators first (9 8 = 72). Multiply the denominators (4 9 = 36). To reduce the answer to its simplest form, divide the numerator by the denominator (72 36 = 2). The fraction 72/36 is equal to 2. Answer: 2

8 72 = 9 ? 8 72 = 9 36 36

72 = 72 36

72

36 = 2

Working with Decimals
A decimal is simply another way to write a number that contains a fraction. A decimal, however, is always a fraction that has a multiple of ten (10, 100, 1,000, and so on) in its denominator. A decimal point (.) indicates the start of a decimal. For example, the decimal 0.5 is equal to the fraction 5/ , which can be simplified to 1/ . The decimal 0.75 is 10 2

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Modern Plumbing, Part 1

equal to 75/100, which can be simplified to 3/4. The fraction 0.125 is equal to the fraction 125/1000, which can be simplified to 1/8. It’s helpful to remember that you work with decimals every time you add, subtract, multiply, and divide dollars and cents. Any price that you see on a tag, such as $3.50, $10.95, or $0.75 is a decimal. The numbers to the left of the decimal point indicate the number of whole dollars in a price, and the numbers to the right of the decimal point indicate the number of cents in a price. Thus, the decimal $3.50 indicates a price of 3 dollars and 50 cents, or 3 1/2 dollars. To quickly convert any fraction to a decimal, divide the numerator of the fraction by the denominator. This is a very useful rule that you’ll use on the job every day throughout your career in the building trades. The following two examples illustrate this rule. Example: Convert the fraction 3/4 to a decimal. Solution: Divide the numerator by the denominator. Use a calculator to do the division.
3 =? 4
Set up the problem.

3

4 = 0.75

Divide the numerator by the denominator. Answer: 0.75

Example: Convert the fraction 7/16 to a decimal. Solution: Divide the numerator by the denominator. Use a calculator to do the division.
7 =? 16
Set up the problem.

7

16 = 0.4375

Divide the numerator by the denominator. Answer: 0.4375

Note that you can convert a mixed number in the same way. Simply convert the fractional portion of the mixed number to a decimal, and keep the whole number part the same. For example, suppose you want to convert the mixed number 2 3/8 to a decimal. You would convert 3/8 to its decimal equivalent by dividing 3 by 8 to get 0.375. The whole number part, 2, would remain the same. When the whole number and decimal parts are combined, you would get the number 2.375.

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37

You may be wondering, “Why do I need to use decimals, when I’ve already learned how to use fractions?” The answer is that professional plumbers will need to use calculators to do most of their more complex math calculations, and most calculators can’t work with fractions. Calculators can only use decimal values. As a plumber, remember that you’ll usually be working with the fractional values that are found on a tape measure, such as fourths, eighths, and sixteenths. Whenever you make measurements, these are the values that you’ll be using. However, when you use your calculator, you’ll need to change the measurements into their decimal form for processing. The following table lists the most common fraction-to-decimal conversions for your reference. These “measuring tape” fractions are very important to the building trades. You should try to memorize the decimal equivalents for all of the fractional parts of an inch down to at least one-eighth of an inch. While you may regularly calculate whole-number problems “in your head,” you’ll usually need to perform the multiplication and division of decimals on paper or with a calculator. Again, always try to estimate an answer before using a calculator to help avoid simple errors.

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Table
Fraction
1/ 1/ 3/ 1/ 3/ 5/ 7/ 1/ 3/ 5/ 7/ 9/ 2 4 4 8 8 8 8

Decimal 0.5 0.25 0.75 0.125 0.375 0.625 0.875 0.0625 0.1875 0.3125 0.4375 0.5625 0.6875 0.8125 0.9375

16 16 16 16 16 16 16 16

11/ 13/ 15/

Sometimes when you’re working with decimals, you’ll want to convert a decimal back to a “measuring tape” fraction. For example, the decimal 0.32 is equal to the fraction 32/100, which can be simplified to 8/25. However, the fraction 8/25 isn’t very useful as a measurement. Instead, it would be more useful to convert 0.32 to a fraction with a denominator of 4, 8, or 16. The following examples show how to convert decimals to useful measuring tape fractions. Example: Convert the decimal 0.32 to the nearest sixteenth. Solution: Multiply the decimal by
0.32 = ? 16
16/ . 16

Set up the problem.

0.32 0.32 = 1

Change 0.32 to the fraction

0.32/ . 1

0.32 1

16 0.32 16 5.12 = = 16 1 16 16
5.12 5 = 16 16

Multiply the fraction by

16/ . 16

Note that the answer isn’t exact. Round off the numerator to the nearest whole number, which is 5. Answer: The decimal 0.32 is equal to approximately 5/16.

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39

In the previous problem, note that the answer was only an approximation. The decimal 0.32 won’t convert evenly to sixteenths. However, the answer is close enough to use when making estimates or approximate calculations. Example: Convert the decimal 0.32 to the nearest eighth. Solution: Multiply the decimal by 8/8.
0.32 = ? 8
Set up the problem.

0.32 0.32 = 1
0.32 1 8 0.32 8 2.56 = = 8 1 8 8

Change 0.32 to the fraction

0.32/ . 1

Multiply the fraction by 8/8.

2.56 3 = 8 8

Round off the numerator to the nearest whole number, which is 3. Answer: The decimal 0.32 is equal to approximately 3/8.

Example: Convert the decimal 0.32 to the nearest fourth. Solution: Multiply the decimal by 4/4.
0.32 = ? 4
Set up the problem.

0.32 0.32 = 1
0.32 1 4 0.32 4 1.28 = = 4 1 4 4

Change 0.32 to the fraction

0.32/ . 1

Multiply the fraction by 4/4.

1.28 1 = 4 4

Round off the numerator to the nearest whole number, which is 1. Answer: The decimal 0.32 is equal to approximately 1/4.

You can also use the values in the conversion chart any time that you need to convert a decimal to fraction. If the value that you’re trying to convert doesn’t precisely match a value on the chart, you can use the value that’s closest. For example, suppose that you want to find the fractional equivalent of the decimal 0.425. Although the exact value 0.425 isn’t on the chart, the value 0.4375 is very close. Thus, a close fractional equivalent for the decimal 0.425 would be 7/16. Measurement

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accuracy in the building trades is normally limited to about a 1/16 of an inch, so estimating a value in this way won’t hurt the accuracy of a finished product.

Adding and Subtracting Decimals
Adding and subtracting decimals is exactly the same as adding and subtracting whole numbers. However, to get the correct answer when you work with decimals, you must keep the decimal points lined up exactly. In the following example problems, note how the numbers have been arranged so that all of the decimal points are lined up. This allows you to place the decimal point in the proper position in the answer. Example: Add the measurements 4.102 inches, 21.245 inches, 1.32 inch, and 2.13 inches. Solution: Write the numbers in a column with the decimal points aligned, then add as you would add whole numbers.
4.102 21.245 1.320 + 2.130
Set up the problem. Note that the numbers 1.32 and 2.13 can be written as 1.320 and 2.130 without changing the value of the number. This method allows you to keep all of the numbers in order as you add the values. Add the numbers as you would any series of whole numbers. Start at the right and add each column of numbers. Answer: 28.797 inches

4.102 21.245 1.320 + 2.130 28.797

You can see that the decimal point in the answer was placed under all of the other decimal points to hold the decimal in its proper location. Most errors that occur when working with decimals are caused by the improper placement of the decimal point in the answer.

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41

Example: Add the measurements 3.41 inches, 36.78 inches, 4.65 inches, and 5.72 inches. Solution: Write the numbers in a column with the decimal points aligned, then add as you would add whole numbers.
3.41 36.78 4.65 + 5.72
Set up the problem.

3.41 36.78 4.65 + 5.72 50.56

Add the numbers as you would any series of whole numbers. Start at the right and add each column of numbers. Answer: 50.56 inches

Example: Subtract 1.25 feet from 4.97 feet. Solution: Write the numbers in a column with the decimal points aligned, then subtract as you would subtract whole numbers.
4.97 1.25
4.97 1.25 3.72
Set up the problem.

Subtract the numbers as you would any series of whole numbers. Start at the right and subtract each column of numbers. Answer: 3.72 feet

Example: Subtract 3.75 feet from 6.9 feet. Solution: Write the numbers in a column with the decimal points aligned, then subtract as you would subtract whole numbers.
6.90 3.75
Set up the problem. Note that the number 6.9 can be written as 6.90 without changing the value of the number. This method allows you keep all of the numbers in order as you subtract. Subtract the numbers as you would any series of whole numbers. Start at the right and subtract each column of numbers, borrowing as necessary. Answer: 3.15 feet

6.90 3.75 3.15

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Modern Plumbing, Part 1

Multiplying Decimals
Decimals are multiplied in the same way that whole numbers are multiplied. However, you must know where to place the decimal point in the answer when the problem is complete. In order to place the decimal point correctly, look at both numbers to be multiplied. Count the number of places to the right of the decimal in each number, and add them together. The sum will tell you the total number of decimal places that you’ll need in your answer. To place the decimal point in the answer, start at the far right of the answer, move the correct number of places to the left, and place the decimal point. This process sounds more complicated than it actually is. Let’s look at a few examples. Example: Multiply 1.75 2.95.

Solution: Multiply the numbers normally, as if there were no decimal points present. Then, count the correct number of decimal places and place the decimal point in the answer.
1.75 2.95
Set up the problem.

1.75 2.95 875 15750 + 35000 51625

Multiply the numbers as if there were no decimal points present. The result of multiplication is 51625.

1.75 2.95

Count the number of places to the right of the decimal point in each number. The number 1.75 has two places to the right of the decimal point, and the number 2.95 has two places to the right of the decimal point. Add the number of places together (2 + 2 = 4) to find the total number of decimal places in the answer. Write the answer. The answer should have four places to the right of the decimal point. Start at the far right of the answer, move four places to the left, and write the decimal point. Answer: 5.1625

5.1625

Lesson 1

43

Example: Multiply 3.9

4.1765.

Solution: Multiply the numbers normally, as if there were no decimal points present. Then, count the correct number of decimal places and place the decimal point in the answer.
4.1765 3.9
4.1765 3.9 375885 + 1252950 1628835
Set up the problem.

Multiply the numbers as if there were no decimal points present. The result of multiplication is 1628835.

4.1765 3.9

Count the number of places to the right of the decimal point in each number. The number 4.1765 has four places to the right of the decimal point, and the number 3.9 has one place to the right of the decimal point. Add the number of places together (4 + 1 = 5) to find the total number of decimal places in the answer. Write the answer. The answer should have five places to the right of the decimal point. Start at the far right of the answer, move five places to the left, and write the decimal point. Answer: 16.28835

16.28835

Dividing Decimals
The division of decimals is much like the division of whole numbers. However, as with the multiplication of decimals, you must know where to place the decimal point in the answer. In the division of decimals, you place the decimal point before you begin to divide. Let’s look at a few examples.

44

Modern Plumbing, Part 1

Example: Divide 9.12 by 1.52. Solution: Move the decimal points as needed, then divide the numbers as you would whole numbers.
1.52 9.12
1.52 9.12

)

Set up the problem. Your answer will go above the division bar. To determine the position of the decimal point in the answer, you must move the decimal point in 1.52 all the way to the right, to the end of the number. Thus, you’ll need to move the decimal point in 1.52 two places to the right. Then, you must also move the decimal point in 9.12 two places to the right. This is how the problem looks now. The decimal point in the answer will be placed directly above the decimal point at the end of 912. Divide the numbers as you would divide whole numbers. Answer: 6

)

152. 912.

)

6. 152. 912. 912 0

)

Example: Divide 4.3505 by 1.13. Solution: Move the decimal points as needed, then divide the numbers as you would whole numbers.
1.13 4.3505 1.13 4.3505

)

Set up the problem.

)

To determine the position of the decimal point in the answer, you must move the decimal point in 1.13 all the way to the right, to the end of the number. Thus, you’ll need to move the decimal point in 1.13 two places to the right. Then, you must also move the decimal point in 4.3505 two places to the right.

Lesson 1

45

113. 435.05

)

This is how the problem looks now. The decimal point in the answer will be placed directly above the decimal point in 435.05. Divide the numbers as you would divide whole numbers. Answer: 3.85

3.85 113. 435.05 339 96 0 90 4 5 65 5 65

)

Example: Divide 13.35 by 2.225. Solution: Move the decimal points as needed, then divide the numbers as you would whole numbers.
2.225 13.35

) )

Set up the problem.

2.225 13.35

To determine the position of the decimal point in the answer, you must move the decimal point in 2.225 all the way to the right, to the end of the number. Thus, you’ll need to move the decimal point in 2.225 three places to the right. Then, you must also move the decimal point in 13.35 three places to the right. (Note that you’ll need to add a zero onto the end of 13.35 to be able to move the decimal point three places to the right.) This is how the problem looks now. The decimal point in the answer will be placed directly above the decimal point at the end of 13350. Divide the numbers as you would divide whole numbers. Answer: 6

2225. 13350.

)

6 2225. 13350. 13350

)

46

Modern Plumbing, Part 1

Performing Decimal Operations with Measurements
When working with measurements on the job, you’ll often find that the measurements are expressed in mixed units, such as 3 feet 1 inch, or 7 feet 11 inches. To perform decimal operations with measurements like these, you’ll first need to convert the measurements to all inches. Let’s look at a few example problems. Example: Multiply the measurement 3 feet 7 inches by the decimal 1.375. Solution: To solve this problem, you’ll need to convert 3 feet 7 inches to all inches, and then multiply. 3 feet 7 inches 3 feet 12 = 36 inches 36 inches + 7 inches = 43 inches
1.375 43
Convert 3 feet 7 inches to inches. You know that 1 foot is equal to 12 inches, so multiply 3 feet by 12 to get 36 inches. Then, add the 36 inches to the 7 inches. Set up the problem.

1.375 43 4125 + 55000 59125

Multiply the numbers as if there were no decimal points present. The result of multiplication is 59125.

1.375

The number 1.375 has three places to the right of the decimal point. Thus, there will be three decimal places in the answer. Write the answer. The answer should have three places to the right of the decimal point. Start at the far right of the answer, move three places to the left, and write the decimal point.

59.125

Lesson 1

47

59.125 = 59

1 8

You can now convert the answer back to a fractional value by using the conversion table. The decimal 0.125 is equal to the fraction 1/8, so the decimal 59.125 is equal to 59 1/8 inches. Answer: 59 1/8 inches

This concludes the basic math review. We hope that you’ll find these example problems to be a useful reference as you work your way through the “Test Your Knowledge” questions in the textbook. After you’ve carefully read pages 84–99 in the textbook, Modern Plumbing, complete the “Test Your Knowledge” on pages 100–101. Check your answers with those provided at the back of this study guide. When you’re sure that you understand the material from this lesson, complete the Lesson 1 examination.

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Modern Plumbing, Part 1

Lesson 1 Fundamentals of Plumbing, Part 1
EXAMINATION NUMBER

Examination Examination

15184500
Whichever method you use in submitting your exam answers to the school, you must use the number above. For the quickest test results, go to http://www.takeexamsonline.com

When you feel confident that you have mastered the material in Lesson 1, go to http://www.takeexamsonline.com and submit your answers online. If you don’t have access to the Internet, you can phone in or mail in your exam. Submit your answers for this examination as soon as you complete it. Do not wait until another examination is ready. Questions 1–20: Select the one best answer to each question.

1. The angle to which the edge of a cold chisel should be ground is A. 90°. B. 60°. C. 45°. D. 25°.

2. OSHA requires that scaffold platforms be made from A. 2 hardwood lumber. B. scaffold-grade lumber. C. 2 softwood lumber. D. 3/4 plywood.

49

FIGURE A-1—Use this figure to answer Question 3.

Floor 3" 60"

Main Stack

??

3. Given a desired slope of 1/4-inch-per-foot and the dimensions shown in Figure A-1, calculate the distance from the top of the soil branch pipe to the floor level (at the point where it attaches to the vertical main stack). A. 6 1/2 inches B. 5 1/2 inches 4. File handles help prevent A. puncture wounds. B. broken files. C. excessive filing. D. dulling the file. C. 4 1/4 inches D. 1 1/4 inches

5. The _______ wrench is least likely to damage plated pipe and fixtures. A. strap B. adjustable 6. A Class C fire is one that involves only A. B. C. D. ordinary combustible materials such as wood, cloth, and paper. live electrical equipment. combustible liquids. combustible metals. C. straight pipe D. monkey

50

Examination, Lesson 1

FIGURE A-2—Use this figure to answer Questions 7 and 8.

36.8" 20"

Front

Top

7. Calculate the volume for the hot water heater in Figure A-2. Assume that water completely fills the dimensioned portion of the heater. A. 736 cubic inches B. 3140 cubic inches C. 3678.34 cubic inches D. 11,555.2 cubic inches

8. Assuming that water completely fills the dimensioned portion of the heater, the capacity of the hot water heater in Figure A-2 would be A. 20 gallons. B. 30 gallons. 9. A transit differs from a builder’s level in that a A. B. C. D. transit uses water to transfer elevations. builder’s level can be mounted on a tripod. transit telescope measures vertical angles. builder’s level isn’t accurate over long distances. C. 40 gallons. D. 50 gallons.

10. Which of the following tools is specifically designed for cutting PVC pipe? A. Saber saw and pipe vise B. Compass saw and chain vise 11. The measurement 86 A. 6 -8 3/4 . B. 7 -2 3/4 .
12/ 16

C. Hacksaw and pipe vise D. Back saw and miter box

inches is equivalent to C. 7 -11 3/4 . D. 8 -6 1/2 .

12. When cutting thin material, such as tubing, a hacksaw blade with _______ teeth per inch should be selected. A. 10 or fewer B. 10–20 C. 20–30 D. 30 or more

Examination, Lesson 1

51

13. The angle to which a wood chisel’s cutting edge should be ground is A. 90°. B. 60°.
FIGURE A-3—Use this figure to answer Question 14.

C. 50°. D. 25°.

14. The smooth-jawed wrench in Figure A-3 A. B. C. D. is correctly positioned to loosen the pipe by pulling up on the handle. is not a tool that you would use with iron pipes. should have a length of 12 inches. will grip tighter as is applied to its handle.

15. The size of a 1/2-inch portable electric drill is determined by the A. B. C. D. largest-diameter hole it will drill in wood. largest-diameter hole it will drill in concrete. largest-diameter bit shank that fits in its chuck. size of its motor.

16. Which of the following tools would be most efficient for drilling a 7 3/4-inch diameter hole in 4-inch-thick steel reinforced concrete? A. Diamond core drill B. Rotary hammer drill C. Hole saw D. Spud bar

52

Examination, Lesson 1

17. The _______ wrench is a good choice to hold or turn a 4-inch pipe when working in a tight space. A. chain B. adjustable C. straight pipe D. monkey

18. A file with _______ cut teeth produces the smoothest finish when filing metal parts. A. rasp B. single 19. When a leveling laser is not in use, it should be A. B. C. D. turned off. recharged. left on and covered with a nonreflective cap. left on and covered with a reflective cap. C. double D. curved

20. OSHA recommends that safety glasses with a number _______ filter lenses be worn when soldering. A. 12 B. 10 C. 6 D. 2

Examination, Lesson 1

53

NOTES

54

Examination, Lesson 1

Fundamentals of Plumbing, Part 2
By the time you complete Lesson 2, you should realize that a plumber’s work involves much more than connecting pipes and fittings. You’ll review basic properties you probably first studied in science class as you learn about the properties of water and how the atmosphere affects its movement through a plumbing system. Every plumber will at some point be expected to read and interpret construction drawings. Even if you lack any artistic ability, you’ll learn an easy way to neatly sketch pipe layouts. Your lesson will also introduce building-code enforcement and explore the building-permit process. Pipes are joined in many ways, including soldering, brazing, and welding. The plumber’s signature tool is his or her torch. While new piping materials and heat-free joining methods are introduced, plumbers will rely heavily on the heated-joint methods for a long time to come. Finally, this lesson concludes with excavation. Digging may not be the most enjoyable part of plumbers’ responsibilities. However, a good knowledge of the available tools and equipment, as well as understanding the right way to use them, makes short work of excavating tasks that might otherwise seem overwhelming. When you complete this lesson, you’ll be able to
I

Lesson 2 Lesson 2

Apply practical methods of computing useful fluid pressures, given the type and size of piping and the head pressures of water systems Recognize the plumbing symbols and abbreviations used in architectural drawings Scale drawings using either an architect’s scale or a rule Prepare two- and three-dimensional piping sketches Describe the ropes and tools suitable for mechanical lifting devices

I

I I I

55

I

Demonstrate different types of ladders and explain how to use them safely List the purpose of building codes and apply them to a plumbing installation Identify the solders, fluxes, and other materials needed for soldering or welding both copper and plastic pipe and fittings Understand the importance of locating and protecting existing underground utilities Develop a list of safety rules regarding the use of excavating machines and shoring methods for workers’ protection

I

I

I

I

ASSIGNMENT 5
Read this introduction to Assignment 5. Then, study Chapter 5, “Hydraulics and Pneumatics,” on pages 103–109 in the textbook, Modern Plumbing.

You can think of the most common goal of a plumber’s work as moving a fluid from one point to another. A plumber’s knowledge of the proper method of joining pipes and installing fixtures is secondary to his or her understanding the basic characteristics of this moving substance. While plumbers are sometimes concerned with the movement of other substances, the moving fluid most often encountered by plumbers is water. While in our everyday lives we don’t often think of water as being a heavy substance, the weight of water (around eight pounds per gallon) has a large impact on how plumbing systems are designed, sized, installed, and supported. You’ve probably not given much thought to the energy required when you pour a glass of water and lift it to drink. A plumber however must carefully consider the energy required to move a specific quantity (or “weight”) of water from a building’s basement to a showerhead on its top story. Of course water’s weight is really just a measure of how much it’s affected by gravity. In this assignment you’ll learn the role played by gravity in moving water. At times the plumber must devise and install systems that overcome the force of gravity, while at other times gravity will be the very force that allows a plumbing system to function.

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Modern Plumbing, Part 1

The practical measurement employed by plumbers to describe the energy stored in water is pressure. Water pressure is typically expressed in units of pounds per square inch or psi. In this assignment you’ll learn how to calculate head pressure, the difference in pressure due to a change in height or elevation within a plumbing system. Plumbers are specifically interested in factors that lead to a loss of pressure within a plumbing system. One such loss introduced in this assignment comes from friction between flowing water the pipe’s interior wall. You’ll learn how different pipe configurations affect the amount of pressure-loss causing friction. At first glance, a pressure loss of a few pounds may seem unimportant when considering the effect on water flow from a third-story showerhead. In this case, a poor system design may result in only the inconvenience of an underperforming showerhead. However, consider a hot-water heating system (known as a hydronic system) that functions at comparatively low pressures. In these systems, the result of an inadequate design causing a pressure loss could be a third-floor room receiving no hot-water heat. While a plumber is often worried about installing a system that keeps water moving, he or she will sometimes encounter applications in which stopping water is just as important. Anyone who has visited the ocean can attest to the tremendous force of moving water. Just as a small wave can knock you down, a valve that closes suddenly can have negative effects on the connected pipe and even the entire plumbing system. Finally, this assignment introduces pneumatics, the impact of air on a plumbing system. You’ll learn where the presence of air must be avoided and where it proves useful to the system. After you’ve read pages 103–109 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 110, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 5, move on to Assignment 6.

Lesson 2

57

ASSIGNMENT 6
Read this introduction to Assignment 6. Then, study Chapter 6, “Print Reading and Sketching,” on pages 111–126 in the textbook, Modern Plumbing.

While the tasks performed by plumbers and architects differ greatly, they often work on the same project and need to communicate. This communication typically takes place without ever meeting face-to-face. Instead, plumbers and architects communicate through their understanding of construction drawings, otherwise known as blueprints or just prints. There are many cases in which you’ll rely on a good ability to read prints. For instance, you might bid a on a job that’s not yet under construction or you might need to design a feasible layout for a bath addition. In this assignment, you’ll learn the terminology and basic practices to follow when reading construction prints. As you’re probably already aware, construction drawings represent three-dimensional (3-D) objects (those that have a height, width, and thickness) like buildings on a two-dimensional (2-D) piece of paper. While it would easier to visualize the intention of a drawing if it showed a building, for instance, in 3-D, the sorts of detailed dimensional data required on a print can’t easily be provided on a 3-D sketch. However, 3-D views are now often available since modern computer-aided design software has revolutionized the way we communicate construction plans. Even so, the plumber on the jobsite will rarely have access to a laptop computer providing a 3-D view of a construction project. Instead, he or she will rely on the ability to use the information from a 2-D construction drawing to form a 3-D picture in his or her head. In this process the plumber obtains dimensions and other detailed data from the drawing’s plan view, elevation view, details views, and specifications. At the end of this assignment you’ll learn how to sketch an isometric view representing a piping system in part or all of a structure. An isometric view represents an object in 3-D. Sketching a pipe layout on isometric graph or dot paper, following the techniques introduced in your textbook, is a great way to master this drawing technique. With a little practice you’ll sketch 3-D layouts anywhere—without a need for special drawing paper. It’s common for the architect

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Modern Plumbing, Part 1

to leave most decisions related to the plumbing system’s design to the plumbing contractor. He or she typically accomplishes this by simply specifying that the system be installed “to code,” meaning that it conforms to local or national plumbing code requirements. The architect’s drawing may show locations of fixtures, water heater, furnace, boiler, water meter, and sewer main without specifying anything else on the drawing related to the plumbing design. This lack of direction offers some positive opportunities and potential drawbacks for the plumber. Of course this approach gives the plumber some freedom to complete the job as he or she sees fit. However, this approach also places greater responsibility on the plumber to correctly complete the job. For example, assume the plumber decides to terminate a roof vent at a particular location while installing the rough plumbing. Later, the job fails final inspection because there’s an operating skylight located too close to the vent. The window wasn’t installed when the plumber installed the vent, but it was clearly indicated on the construction drawings. The general contractor will hold the plumber responsible for misplacing the vent, and the plumber bears the cost of correcting the mistake. Careful study of construction prints eliminates costly mistakes and lost time. In addition to the drawings found on a construction print, many notes are often added in a specification section. From the plumber’s perspective, this part of the print deserves special attention. As you’ve just learned, an architect may choose to describe very little of the building’s plumbing system in his or her drawings, but may include a large amount of related detail in the written specifications (or specs). If a particular pipe material or fixture model number is specified here, the specified instructions must be closely followed. It’s probably obvious to you that construction drawings can’t be produced at a size equal to what they represent. Of course, if they were produced at the same size as the building, it would be pretty simple to directly measure dimensions. A more practical (and typically encountered) drawing size measures 36 inches by 24 inches. Representing a building on this size print requires that the drawing be scaled so that the required information fits on the sheet of paper. It’s up to the person drawing a particular job to choose an appropriate scale that satisfies typical drawing conventions. The ultimate goal is to fit as much

Lesson 2

59

information (at the desired amount of detail) on a standard drawing sheet size that users can conveniently read. Standard symbols and abbreviations related to plumbing and many other systems are incorporated on the print to maximize the amount of information represented. When an unusual symbol occurs, it’s often defined in the drawing’s notes or in a particular part of the drawing known as a key. As a plumber, you should memorize plumbing system–related symbols and abbreviations that most often appear on construction prints. Sometimes several pages are employed to represent one view of a particular job in the desired detail. In this case, match lines are located on the edge of the adjoining sheets. Determining dimensions from a scaled print is relatively easy, especially when the drawing is made to a common scale such as onequarter inch drawing size equals one foot. An architect’s scale eliminates the need to convert measured lengths to actual ones by providing scales that match those typically found on construction prints. With the appropriate architect’s scale, distances represented by the scaled print can be directly measured. After you’ve read pages 111–126 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 127, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 6, move on to Assignment 7.

ASSIGNMENT 7
Read this introduction to Assignment 7. Then, study Chapter 7, “Rigging and Hoisting,” on pages 129–135 in the textbook, Modern Plumbing.

It should be obvious to you by now that a plumber’s job responsibilities include installing many types of materials and equipment. However, remember that it’s also often his or her responsibility to move the work materials to their intended point of installation. Many of the materials, fixtures, and equipment installed by plumbers are too heavy for one, two, or even several people to safely move or lift. In other instances, the quantity of items to be moved or the path over

60

Modern Plumbing, Part 1

which they must travel (such as up ladders and across scaffolding) makes them impractical to transport manually. Proper use of hoists and mastery of rigging techniques like those described in your textbook make these otherwise physically overwhelming tasks possible and safer. This assignment introduces methods and equipment for handling heavy supplies and equipment. A rigging task can be as simple as supporting one end of a pipe while a lone plumber joins the other, or as complex as raising an air conditioner to the rooftop of a multifloor commercial building. While the safe use of ladders was introduced earlier in your course, this assignment offers more detailed instruction on selecting the proper ladder for a job as well as care of ladders. A plumber usually knows when a particular day’s tasks will require a ladder. This means he or she won’t typically find it necessary to haul a complete assortment of ladders on a daily basis. However, you may find it helpful to normally bring an articulating ladder to the jobsite as a handy backup for those times when a ladder is unexpectedly required. After you’ve read pages 129–135 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on pages 136, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 7, move on to Assignment 8.

ASSIGNMENT 8
Read this introduction to Assignment 8. Then, study Chapter 8, “Building and Plumbing Codes” on pages 137–142 in the textbook, Modern Plumbing.

The plumbing industry directly affects the health of those who occupy or enter any space with running water. For this reason, modern plumbers would find it hard to locate a place where they’re legally allowed to operate without some form of government supervision. The most basic form of government supervision is building codes, or rules considered to be the minimum safe practice for any particular construction task. Rules that specifically apply to a plumbing installation are outlined in a plumbing code. Some of a plumber’s duties involve

Lesson 2

61

alterations to the building structure to make room for pipes or other equipment. Other codes dictate that these alterations don’t turn an otherwise sound structure into an unsafe one. All plumbers should have a good understanding of the codes that apply to the work they routinely perform. Develop the consistent habit of referring to an up-to-date code book whenever performing a task that, for you or your coworkers, isn’t routine. A code enforcement officer is responsible for inspecting your work, which will either pass or fail. The officer’s responsibility doesn’t include explaining how to pass a follow-up reinspection. Instead, expect him or her to show what specific part of the code has been violated. While this assignment focuses on how to obtain a permit and what to expect during the code inspection process, you should also become familiar with interpreting the initially confusing (but eventually understandable) language found in plumbing codes. After you’ve read pages 137–142 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 143, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 8, move on to Assignment 9.

ASSIGNMENT 9
Read this introduction to Assignment 9. Then, study Chapter 9, “Soldering, Brazing, and Welding” on pages 145–152 in the textbook, Modern Plumbing.

Proven as a secure, cost effective, and quick means of joining copper pipes, soldering has been the most popular method for many years. In this assignment you’ll learn how the soldering process works and the techniques applied when soldering. Recognizing factors that prevent successful soldering operations is just as important as knowing the correct application techniques. The physical and chemical characteristics of the soldering operation allow for pipes to be joined in configurations that may be otherwise impossible. For instance, mechanically joined pipe joints require clearance for wrenches or other tools. A properly prepared solder joint can be successfully completed with a minimal amount of space.

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Modern Plumbing, Part 1

While the basic characteristics of a brazed and soldered joint are the same, the higher temperatures required to melt the braze filler metal involves a bit more skill and special torch equipment. Usually, high-pressure lines and pipes are specified to be brazed instead of soldered. All air-conditioning applications require brazing. Even low-pressure applications that might be subject to vibration require brazing rather than soldering. When compared to soldering or brazing, welding is by far the joining process requiring the most skill and leaving the least room for error. During the welding process, the heated pipe material reaches a molten stage, creating a one-piece joint as strong as the pipe itself. Metal pipe welding is a specialized skill that’s not mastered by all plumbers. Much like steel pipe, PVC pipe can be heat-welded. However, in the PVC welding process the flame or arc is replaced by highly heated air that brings the plastic to a molten state. Unlike metal-pipe welding, plumbers can quickly master the PVC-welding technique. Whichever process you employ, joint preparation is the key to successfully making heated pipe joints. Cleaning the parts prior to joining and keeping them clean during the heating process is critical. In this assignment you’ll learn the critical role played by flux in these operations. After you’ve read pages 145–152 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 153, check your answers against those provided in the back of this study guide. When you’re sure you completely understand the material from Assignment 9, move on to Assignment 10.

Lesson 2

63

ASSIGNMENT 10
Read this introduction to Assignment 10. Then, study Chapter 10, “Excavating” on pages 155–165 in the textbook, Modern Plumbing.

While most plumbing work is installed above ground, occasionally you’ll work with buried pipes. Whether installing a new plumbing system or repairing a problem with an existing underground pipe, you’ll eventually need to dig or excavate. On large-scale projects, much of the excavation is left to a contractor who specializes in such work. Because the underground installation of a pipe or group of pipes requires a very narrow amount of space, plumbing excavation is usually limited to trenching, which is accomplished with either hand tools or smaller machines. The first step in any excavation job involves locating all existing underground utilities. It’s illegal for even a homeowner to dig without completing this important step. In most areas, this task requires only one phone call and a few days to complete. The width and depth of a trench depends on the type of pipe and the methods required to install it. A sewer line might require a very deep trench with room for workers to make connections in the trench. On the other hand, a flexible one-piece gas line requires only enough room for the pipe. The preferred method of excavation depends on the trench size, the material to be removed, and the equipment available. This assignment describes safe handling techniques and applications for digging hand tools. It also describes some popular excavating machines you might encounter. Most of these smaller excavating machines are easy to learn to operate and readily available to rent. Every excavating job is unique in that the plumber must determine what tools, equipment, and methods would best suit the situation. For example, it’s impractical to spend days hand-digging a 9-foot-deep trench 50 feet long when a machine could accomplish the job in a matter of hours. On the other hand, space limitations also often dictate the best method of excavation. Imagine the problems that could be encountered if you try to move a full-size backhoe onto a lot measuring 20 feet by 20 feet and surrounded by buildings.

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Modern Plumbing, Part 1

After you’ve read pages 155–165 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 166, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from this lesson, complete the Lesson 2 examination.

Lesson 2

65

NOTES

66

Modern Plumbing, Part 1

Lesson 2 Fundamentals of Plumbing, Part 2
EXAMINATION NUMBER

Examination Examination

15184600
Whichever method you use in submitting your exam answers to the school, you must use the number above. For the quickest test results, go to http://www.takeexamsonline.com

When you feel confident that you have mastered the material in Lesson 2, go to http://www.takeexamsonline.com and submit your answers online. If you don’t have access to the Internet, you can phone in or mail in your exam. Submit your answers for this examination as soon as you complete it. Do not wait until another examination is ready. Questions 1–20: Select the one best answer to each question.

1. A column of water 10 feet tall exerts a pressure of _______ pounds per square foot at the base. A. 62.4 B. 124.8 C. 144 D. 624

2. A set of blueprints shows the location of bathroom fixtures in a residence. The _______ identifies the correct drain pipe size used to connect them. A. specifications on the prints B. plumber’s experience C. plumbing code D. architect’s notes

67

12'-5/8"

8'-13/16" 7'-2 5/8" Gas
WH

8'-9 3/4"

24'-8"

15'-4 7/16"

16'-3 5/8"
FIGURE A-4—Use this figure to answer Question 3.

3. Figure A-4 shows a basement floor plan where the walls are constructed of 8-inch concrete blocks. Considering a new gas line from a point “X” in the existing structure, approximately how much pipe will be needed to provide a connection for the new water heater? (Assume the pipe’s route follows the most direct path possible.) A. 40 feet B. 30 feet C. 25 feet D. 20 feet

4. If friction produces head loss of 11 feet per 100 feet of 1/2-inch copper pipe, what will the pressure loss be for 50 feet of this same pipe? A. 12.7 psi B. 5.5 psi C. 4.73 psi D. 2.365 psi

5. To avoid unwanted wear, ropes used for hoisting loads should not be A. kept dry. B. run across sharp edges. C. coiled. D. exposed to sunlight.

68

9'-7 11/16"

Examination, Lesson 2

6. Tools, fittings, and lightweight supplies can be safely and efficiently passed to workers on a scaffold, whose height measures 15 feet, by employing a _______ attached to the scaffold. A. lever hoist B. hoist standard 7. Plumbing installations must be inspected A. B. C. D. before the pipes in the walls are covered. before the fixtures are purchased. after the water supply piping is extended inside the foundation. before the water heater is installed. C. winch crane D. lift platform

8. Model plumbing codes are intended to A. B. C. D. standardize pipe and fitting sizes. standardize fixture styles. protect the health and safety of plumbers. provide example codes that can be locally adopted.

9. Pressure head of 120 inches of water produces _______ psi of pressure. A. 0.43 B. 2.31 C. 4.3 D. 23.1

10. To ensure an excellent bond when brazing, the clearance gap between pipe and fitting must be A. .002 to .004 inches. B. .002 to .005 inches. C. .003 to .004 inches. D. .004 to .006 inches.

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FIGURE A-5—Use this figure to answer Questions 11–12.

A

B

C

D

11. Which torch position in Figure A-5 would be a correct starting point to solder the lowest joint? A. Torch position A B. Torch position B C. Torch position C D. Torch position D

12. Which torch position in Figure A-5 would be correct as you’re feeding solder into the lowest joint? A. Torch position A B. Torch position B C. Torch position C D. Torch position D

13. The pressure on the bottom of a water tank filled to a depth of 4 feet is A. 1.72 psi. B. 62.4 psi. C. 184.2 psi. D. 249.6 psi.

14. A type of shovel that’s intended for digging and is also designed to throw material from one location to another is the A. drain spade. B. round-point. C. square-point. D. long-handle.

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15. Two homes share the same water main. Home A is located 20 feet higher than home B. If home A’s inlet water pressure measures 60 psi, what would you expect the inlet pressure to measure at home B? A. 60.86 psi B. 64.3 psi C. 68.6 psi D. 686 psi

16. The water service pipe connecting the building to the water main must be buried below the _______ or at a minimum of 12 inches. A. B. C. D. frost line building sewer gas pipe depth of all other buried utilities

17. Removing the metal burr from the inside of pipe is known as A. reaming. B. brazing. 18. The strongest grade of manila rope is A. No. 1. B. No. 2. C. No. 3. D. yacht. C. fluxing. D. oxidizing.

19. It’s best to apply a coat of _______ to keep a wooden ladder structurally sound and functioning well. A. oil-based paint B. linseed oil 20. _______ fluxes are best suited for plumbing work. A. Corrosive B. Noncorrosive C. Variable D. Zinc cloride C. clear sealer D. metallic paint

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Water Supply and Fixtures

Lesson 3 Lesson 3

The early assignments in this lesson explore the foundation of all plumbing systems, a fresh water source. Assignment 11 primarily focuses on private water systems, with the addition of a few details related to municipal or public systems. You’ll learn how wells, well pumps, and pressure tanks work together to obtain water from underground sources. Of course, a fresh water source isn’t necessarily a clean water source. Assignment 11 explains the importance of well location and how the surroundings can affect the quality of a fresh water supply. The next assignment describes the impurities that can be found in any water source. Water treatment methods remove or reduce levels of impurities to ensure that the water from any source is both healthy and appealing for human consumption. This lesson ends with a look at the wide array of plumbing fixtures available today, including a description of the diverse materials from which fixtures are manufactured. You’ll learn to appreciate that our dwelling’s hot and cold water supply is really an invaluable tool that we use in nearly every part of day-to-day life. Modern plumbing fixtures not only make life easier, but they can make life more enjoyable. In fact a welldesigned bathroom treats the plumbing fixtures as the center of focus. When you complete this lesson, you’ll be able to
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List pump and well types and explain their construction Identify potential water contaminants Explain the purpose and operation of a pressure tank Describe devices used to treat and disinfect water, and explain how they work Recognize the materials from which fixtures are manufactured Identify various fixture types Distinguish between the different types of toilets

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ASSIGNMENT 11
Read this introduction to Assignment 11. Then, study Chapter 11, “Water Supply Systems,” on pages 169–185 in the textbook, Modern Plumbing.

Any structure in which humans reside or work must contain a source of usable water. In fact, human civilization has grown up around reliable sources of fresh water from the beginning of recorded history. Look at any map, find an established urban environment, and you’ll most likely find a nearby freshwater lake or river. It’s only by developing the ability to access a less visible water supply that human civilization expanded into areas away from fresh bodies of water. This invisible source rests under our feet, sometimes below hundreds of feet of dirt, clay, or rock. In this assignment you’ll learn how we access this water stored below the surface as you study wells and water pumps, two technical developments that help humans access reliable water supplies in almost any location. A well is simply the hole through which we access the underground water supply. Whether that access is drilled, bored, driven, or dug, the result is the same. A single large well in the right location can supply many people with unlimited water on demand. More popular are smaller wells for use by one structure or one home. Well installation is work that’s done by a specialist. The plumber is more concerned with getting the water from the source to the dwelling, rather than actually accessing the source. Water leaves the well with the help of a pump and travels through a storage tank or pressure tank. Plumbers are responsible for installing and maintaining the pumps, tanks, and connecting pipes in private water-supply systems. Well pumps are classified as centrifugal pumps. To understand how they work, first consider that a centrifugal pump operates much like your shop vacuum. Inside the vacuum is a motor that moves air by spinning a turbine or fan. Air that’s pushed out of the vacuum’s exhaust is replaced by air entering its intake. Of course, in a shop vacuum, the intake is connected to a hose into which debris is drawn along with the rush of air entering the intake. Most shop vacuums move water, as well as dry debris, with some limitations. Water is

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very heavy compared to air. While a shop vacuum might move many gallons of water through a few inches of elevation (from a basement floor spill into its tank), it couldn’t move even a teaspoon of water from the depths of a relatively shallow well. Well pumps are specifically designed to move liquids. Instead of a fan (like the shop vacuum) the pump incorporates an impeller, which much more efficiently moves liquids. As the impeller pushes water out of the pump and toward the surface, replacement water is drawn into the pump through its supply port. Because water is much heavier than air, the exiting water creates a force that’s much greater than could be created by moving air through the shop vacuum. While the well pump does a great job of moving water, it can’t move air. To function, the pump must be free of air and full of water. This means that the pump must be primed before it moves water. Priming a pump refers to removing any air contained in the pump’s casing and replacing it with water. Water pumps include a port through which the plumber fills it with water, displacing the air held inside the casing. Once primed, the pump functions normally by pulling water into its casing through its suction port and forcing water out of its exit (or pressurized) port. When a primed pump stops pumping, gravity forces the water contained in its supply piping to drain back into the well, returning to the water in the piping to the natural water level in the well. If this action were allow to proceed, it would draw the water out of the pump casing, requiring the repriming of the pump every time it went through a start-and-stop cycle. To maintain a primed pump, a one-way check valve is installed at the base of the well piping. This foot valve allows water to flow in the direction of the pump’s discharge but not in the opposite direction. This keeps even an idle pump full of water. Wells are dug to a sufficient depth to provide a constant and permanent supply of water. Drawing or forcing water from deeper wells requires more pumping force. One way to produce this force is with larger, more powerful pumps. Other more energy efficient methods are explained in this assignment. First is the installation of a simple jet nozzle in the pipe entering the well to substantially increase a smaller

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pump’s capacity. The resulting system, known as jet pumps, are by far the most popular means of supplying water from all but the deepest wells. For those deeper wells, we turn to submersible pumps, which are installed inside the well. With these pumps there’s no priming required as the pump rests well below the well’s water line. When supplied by a municipal water source, residential water pressure is fairly constant over a period of time. However, in a well-supplied or private water source, the supply pressure is determined by the regulation of the well pump. If for instance the well-pump is regulated to supply water at 40 psi, the system would probably switch the pump on when system pressure drops to about 30 psi and off when it reaches 50 psi. In this configuration, the pump would cycle on and off many times during the course of normal, daily household use. Without a reservoir that’s more substantial than the volume of water held in the well’s supply pipe, drawing a glass of water from the kitchen sink would quickly cause the system pressure to drop from the 50 psi to 30 psi pump-control set points, resulting in a nearly constant cycling and shortlived pump. To prevent this problem, a storage or pressure tank is installed between the well pump’s supply pipe and the rest of the plumbing system. This creates a pressurized reservoir and eliminates the pump’s frequent cycling. Since water isn’t very compressible, pressurizing a 40-gallon storage tank to 50 psi won’t do much to improve the short time between pump cycling. Air, on the other hand is quite compressible, so the reservoir maintains an air pocket in the top of its tank, which is compressed by the incoming pressurized water. This pressurized air pocket provides a more steady force to move the water from the tank into the home’s plumbing system. The inclusion of air in the water storage tank is referred to as a hydropneumatic system. After you’ve read pages 169–185 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 186, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from Assignment 11, move on to Assignment 12.

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ASSIGNMENT 12
Read this introduction to Assignment 12. Then, study Chapter 12, “Water Treatment,” on pages 187–195 in the textbook, Modern Plumbing.

In a public municipal water system, it’s the water authority’s responsibility to make sure water coming out of any tap is safe to consume. In a private system, the system’s owner must ensure that water delivered to the dwelling is safe to consume. Private water sources should be analyzed for impurities and, when required, an appropriate treatment program put into place. The main goal of a water treatment system is the delivery of potable water, which means water that’s safe to drink. Water that’s potable isn’t necessarily good tasting or even visibly clear. Some treatment methods simply remove sediment or control mineral levels. Often this treatment strives to improve the taste or clarity of water that’s otherwise perfectly safe to consume. Other impurities, such as bacterial pathogens, are extremely harmful. Treatment of water sources infected with these substances then becomes critical. This assignment introduces methods of water treatment from simple filters to complex bacteria-removing systems. Plumbers may sometimes perform simple pH tests, but all other more-complex testing duties are typically left to a laboratory. A plumber should be able to read the laboratory’s test results, note the impurity concentrations indicated, and install the correct type of treatment system sized to handle the system’s water usage level. At times the plumber installs a series of treatment devices in the same system. For instance, a chemical like chlorine might be effectively added to kill bacteria, then removed by another treatment device to improve taste. This assignment’s discussion of treatment technologies shouldn’t indicate that all fresh water requires filtration and treatment. In fact, much of what’s found in our drinking water benefits our health and actually makes water taste better.

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After you’ve read pages 187–195 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on pages 196–197, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from Assignment 12, move on to Assignment 13.

ASSIGNMENT 13
Read this introduction to Assignment 13. Then, study Chapter 13, “Plumbing Fixtures,” on pages 199–210 in the textbook, Modern Plumbing.

This part of your textbook focuses on plumbing fixtures, the part of the plumbing system that’s most visible to the dwelling’s occupants. For this reason, fixtures are selected based on both functional and decorative considerations. Today’s plumbing fixtures are often produced from the same materials used for decades or even centuries, including porcelain-coated cast iron and vitreous china. These materials have endured generations of constant use. Other fixture materials include fiberglass and plastic polymers, inexpensively molded into nearly any imaginable shape and color. The evolving design of sinks, tubs, showers, and toilets focuses on visual appeal as well as many other special needs. For instance, fixtures are now readily available for people with special physical needs. Other modern fixture designs include jetted bathtubs produced in many sizes, corner-mounted fixtures that make use of limited space, one-piece shower stalls that eliminate any leakage or cleaning problems at seams, and showers equipped with multiple spray heads. Fixture design also addresses the need for water and energy conservation. These models must reduce consumption while maintaining or improving fixture performance. The extensive variety of fixtures brings new challenges for the plumber. While many fixtures are produced with standard supply and drain locations, some specialty fixtures incorporate unconventional piping locations. Plumbers must consider these needs during the job-planning stage, even though fixture mounting is usually accomplished as a finish operation. Failure to plan results in costly time loss as the

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plumber must move the rough plumbing during later stages of construction. Fortunately, fixture manufacturers provide detailed rough plumbing dimensions in their specification sheets. After you’ve read pages 199–210 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 211, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from this lesson, complete the Lesson 3 examination.

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Lesson 3 Water Supply and Fixtures
EXAMINATION NUMBER

Examination Examination

15184700
Whichever method you use in submitting your exam answers to the school, you must use the number above. For the quickest test results, go to http://www.takeexamsonline.com

When you feel confident that you have mastered the material in Lesson 3, go to http://www.takeexamsonline.com and submit your answers online. If you don’t have access to the Internet, you can phone in or mail in your exam. Submit your answers for this examination as soon as you complete it. Do not wait until another examination is ready. Questions 1–20: Select the one best answer to each question.

1. The production of fixtures with vitrified porcelain A. B. C. D. requires a metal base. has been abandoned. requires extremely high temperatures. is fast and inexpensive.

2. Which of the following is not a potential source of groundwater pollution? A. B. C. D. Waste disposal sites Livestock feedlots Underground fuel tanks Surface water evaporation

3. Forcing a well point into the ground produces a type of well known as a _______ well. A. bored B. driven C. forced D. drilled

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4. Using a zeolite water softener as a water treatment A. B. C. D. requires a soda ash /chlorine tank. kills bacteria. may increase salt levels in your diet. requires regular filter cartridge replacements.

5. The amount of air pressure in a water-pressure storage tank is A. B. C. D. referred to as supercharge. removed by a vacuum break. always maintained at 50 psi. directly related to the supply piping diameter.

6. A submersible pump’s capacity depends on the A. B. C. D. size of the pressure tank it supplies. size of its check valve. number of impellers. level of backpressure from fixtures installed in the plumbing system.

7. Tapping a municipal water supply for a new residence would most likely A. B. C. D. help remove air from the municipal system. improve alkaline pH levels. only occur where shallow wells are common. not interrupt the neighbor’s water supply.

8. Water whose pH value measures five is considered A. neutral. B. acidic. C. alkaline. D. hard.

9. To successfully obtain water, a well must extend into A. the sand layer. B. the frost line. C. soil and clay. D. an aquifer.

10. Hydrogen sulfide gas is best removed by _______ followed by _______. A. B. C. D. filtration, water softening chlorination, filtration sediment filtration, chlorination sediment filtration, activated charcoal filtration

11. Water containing bacteria, protozoa parasites, and viruses is made potable through treatment with A. chlorine. B. a sediment filter. C. an activated charcoal filter. D. a clarifier filter.

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12. Water is decontaminated by being forced through a membrane in a process known as A. reverse osmosis. B. ultraviolet. C. distillation. D. backflushing.

13. Adding _______ is one way to neutralize acidic water. A. chlorine B. soda ash 14. Commonly encountered shower bases A. are installed after the surrounding walls are finished. B. come in standard sizes whose lengths measure either 4 feet 6 inches, 5 feet, or 5 feet 6 inches. C. are no longer produced from plastics. D. come in standard sizes that measure either 30 by 30 inches, 36 by 36 inches, or 36 by 48 inches. 15. A _______ pump employs a venturi tub to increase water pressure. A. jet B. lift C. centrifugal D. helical C. hydrogen sulfide D. potassium permanganate

16. Exposing water to ultraviolet light is an effective way to A. kill bacteria. B. remove dissolved minerals. C. remove gasses. D. measure impurity levels.

17. Which of the following well installation methods is best for producing the deepest wells? A. Percussion drilled B. Driven 18. A well’s top is closed in the process known as A. grouting. B. capping. 19. Sodium hypochlorite is A. B. C. D. used in water softeners for ion exchange. the chemical compound that makes up bleach. effective for removing organic chemicals. a mineral found naturally in most private wells. C. sealing. D. filling. C. Dug D. Rotary drilled

20. Water treatment systems remove dissolved calcium and magnesium through the process of A. reverse osmosis. B. pasteurization. C. filtration. D. ion exchange.

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Fittings, Valves, and Heaters
The plumbing trade has been around for centuries. In fact, the word “plumbing” comes from the Latin word for lead, plumbum. Now branded as harmful to humans when ingested, lead was for many centuries considered a miracle product for pipe production. It’s easy to mold into a tubular shape and highly resistant to corrosion. Unearthed early Roman lead-pipe systems contain remnants that still hold water. Most homes built prior to 1930 used lead pipes in at least part of their plumbing system, and as recently as the mid 1980s, it was not illegal to use lead products in residential plumbing systems. Today we have many choices for pipes and fittings, none of which contain lead. While they’ve been installed for several years, plastic pipes and fittings are comparatively new. However, many types show promise of being the new “miracle” material. This lesson begins with a look at available pipe materials. You’ll learn how different types of pipe and tubing are sized and graded, which fittings are employed in various installations, and how plumbers identify each unique type of fitting. You’ll then study valve names and types while learning where in a plumbing system you’re likely to encounter them as well as their purposes and benefits. The lesson ends with detailed discussion of water heaters. The plumber isn’t traditionally expected to know every detail of every appliance that might be attached to the plumbing system. A washing machine, water cooler, and icemaker are all appliances for which a plumber would install pipes without ever understanding the details of their interior workings and design. That’s partly because when something goes wrong with those appliances, a specialized repairman is usually called. However, a water heater is an appliance for which a plumber is typically the specialized repairman. Therefore, it’s necessary that you develop a thorough understanding of this critical appliance.

Lesson 4 Lesson 4
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When you complete this lesson, you’ll be able to
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Name various materials used in pipes and fittings and suggest appropriate application of each List grades and sizes of pipes and fittings and interpret markings Recognize different types and applications of plumbing valves and meters Illustrate the operation of different valves and meters Differentiate between the two types of water heating systems and explain their operation Explain installation and control of water heating systems

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ASSIGNMENT 14
Read this introduction to Assignment 14. Then, study Chapter 14, “Piping Materials and Fittings,” on pages 213–242 in the textbook, Modern Plumbing.

Just as the manufacture of plumbing fixtures has evolved over recent years with the addition of many new moldedplastic products, pipes and fittings are also often made from molded plastics. However, just as you learned that many older fixture materials (such as porcelain) are still in use, so are historically popular metal (especially copper) pipes and fittings. In fact, copper supply lines are still widely produced and preferred by many plumbers and consumers. Drain, waste, and vent (DWV) piping installed today is overwhelmingly plastic (especially ABS and PVC). Plastic piping has become the most popular choice for this application because it’s lighter in weight, less expensive to purchase, and easier to install than historically popular alternatives. Plastic’s ability to be affordably molded into any imaginable shape allows for countless fitting configurations. A joint that may previously have required three or more cast-metal fittings is now cheaply molded into a one-piece joint-free plastic combination fitting. Virtually all homes built prior to the early 1960s utilized cast iron pipes for the main drain and galvanized steel for branch drain and vent pipes. Joining cast iron pipe

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was somewhat of an art, requiring plumbers to pour molten lead into the hub of each joint. Galvanized pipe joints require threaded pipe ends and wrench-tightening each joint. Plastic pipe can be cut with nearly any saw, and joints are created with glue that dries in seconds. It’s easy to see how ABS and PVC piping have all but totally replaced metal pipes in DVW applications. As with all plumbing materials, however, there are disadvantages to using plastic pipe. For instance, the length of a plastic pipe grows or shrinks much more than a metal pipe when exposed to changes in temperature. Hot water from a tub, shower, or washing machine causes the drain pipe to expand rather quickly, sometimes leading to pipe noise and (in extreme cases) the need for expansion joints in longer pipe lengths. Noise is more apparent as water travels though plastic pipe compared to metal, leading to drain-placement restrictions and (again, in extreme cases) the need for sound insulation. These disadvantages of plastic have left a market for cast iron use in some drainage systems. Modern hubless cast iron products no longer require the use of molten lead to seal joints. Even with this easier installation method, cast iron still can’t compete with the low cost of plastic for most DWV applications. The current market for water-supply piping doesn’t lean so heavily toward plastic pipe. The use of plastic pipes for applications is relatively new compared to its use in DVW applications. Pressurized water supply lines subject to physical damage, as well as gas supply lines are best plumbed in copper. For installations that are concealed or buried, many plumbers won’t accept the potential problems plastic pipe can cause, even considering its lower material cost. PEX plastic pipe is increasingly popular for water supply in new home construction. It’s flexible enough to make turns around obstacles without fittings and available in roll lengths that allow jointless runs to fixtures. PE pipe offers the same advantages when used for gas lines. Even if plastic pipe effectively replaces copper pipe in new installations, the amount of existing copper plumbing will require plumbers to successfully repair and expand these systems for many years.

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This assignment provides a detailed overview of the materials, fittings, and joining methods of modern and historically popular plumbing systems. Concentrate on the materials available as well as where, why, and how these materials work best. For instance, a threaded pipe maintains a watertight joint very differently than a threaded brass compression fitting or a threaded flared connection. Learn from your reading why you should choose to connect an oil furnace supply line with a flared connection rather than threaded pipe. Also learn why you wouldn’t install PEX pipe instead of copper when connecting a central air conditioner. Recognizing the benefits and limitations of products helps you create safe and practical solutions to any plumbing installation needs. After you’ve read pages 213–242 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 243–244, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from Assignment 14, move on to Assignment 15.

ASSIGNMENT 15
Read the entire introduction that follows. Then, study Chapter 15, “Valves and Meters,” pages 245–255 in your textbook, Modern Plumbing.

Plumbing systems are controlled with various types of valves, devices that regulate the delivery of liquids and gases. From the consumer’s perspective, the only valves of any significance are the most obvious ones, those located at fixtures. Faucets valves can be simple in design. A shower might be controlled with nothing more than a couple of compression valves, the simplest and most common valve found in many locations within a plumbing system. On the other hand, faucets can be quite complicated, such as a shower control that automatically adjusts for temperature change. This feature provides safety as well as added comfort for the user. This assignment introduces some of the less visible valves in plumbing systems. Recall from your earlier studies that a well-water delivery system requires a foot valve to prevent water from traveling back into the well. A foot valve is a good

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example of a one-way directional valve, or check valve. Check valves can also be used to isolate potable water supply from other parts of the plumbing system. For instance, even though hydronic heating systems operate in a closed loop, they require that a water supply be automatically available in the event of a leak. This requirement prevents the catastrophic failure that can occur if a system leak causes the boiler to run out of water. Without a check valve at this location, a drop in water-supply pressure would cause heating-system water to move into the potable water supply. At sanitary fixtures (such as toilets), contaminated water must stay in the drain system. Flush valves at those locations must also act as check valves. Vacuum breaks are used at these locations to insure that the drain system remains isolated from the supply. Most plumbing codes require even a hose bib to incorporate a vacuum break to ensure the quality of the potable system. Whether watering the lawn or selecting that perfect temperature for the morning shower, most of the valves at points of use are controlled by human hands. Other valves, like the check valve, are designed for purposes that don’t require direct human intervention and can therefore be thought of as unattended valves. Some of these valves are installed as safety measures. This is the case with temperature and pressure relief valves (or T/PRV ). Their purpose is to stop a bad situation from becoming a catastrophic event. A malfunction in a boiler or hot-water heater could result in a violent explosion. These valves hopefully never actually function, but their presence certainly serves a valuable role in the plumbing system. Gas appliances use valves that are totally unattended as well. When a thermostat on a gas furnace or hot-water heater determines there’s a call for heat, the main gas valve opens, supplying fuel to the appliance and allowing the burner to ignite. Modern gas appliances are also being fitted with special valves that sense an abnormal amount of fuel flowing through the system, which would indicate a possible leak. The valve would subsequently close, shutting down the main supply to the appliance.

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Another unattended valve is the pressure regulator. Pressure regulators are located where a reduction of main water pressure, for instance, is desirable. One common application for pressure regulators is the inlet to a hydronic heating system. At times the municipal water-supply pressure exceeds the practical capacity of a building’s water-carrying pipes. In this case, a pressure regulator maintains a constant usable pressure that’s safe for the pipes and users. Pressure regulators are often installed at gas appliances, preventing difficulties that would arise from a fluctuating supply pressure. Without such a regulator, the stove’s flame could easily increase or decrease in intensity, without human control, when the gas furnace or gas hot-water heater cycled off or on. Valves are placed throughout plumbing systems to facilitate future maintenance. Some of these valves, like stop valves at appliance locations and at the point the water or gas enters the structure are required by the plumbing code. A wise plumber locates valves at places that make service or expansion easier, allowing for the service of small segments rather than shutting down and draining the entire system. A stop and waste valve, located where the system’s pipe rises to an upper floor, allows the lower floor to remain in service while work is performed on the upper floor and simplifies the process of draining only the upper floor’s pipes. In another configuration intended to ease maintenance, ball valves are installed on either side of a water filter to ease the task of changing the filter cartridge. The amount paid by municipal water or gas consumers depends on the amount of water or gas they use. Meters installed where the supply plumbing enters the building measure either the gallons of water or cubic feet of gas entering the building. While there’s no usage meter needed on the private water system, a meter might be found on the water treatment system. In this case the meter might signal a backwash cycle to clean the system’s filters after a specific number of gallons. As a backwash cycle consumes a relatively large amount of water, scheduling the backwash based on the quantity of water filtered rather than relying on a conventional time clock, conserves water and maintains a consistent level of quality in the potable water supply.

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After you’ve read pages 245–255 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 256, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from Assignment 15, move on to Assignment 16.

ASSIGNMENT 16
Read this introduction to Assignment 16. Then, study Chapter 16, “Water Heaters,” on pages 257–270 in the textbook, Modern Plumbing.

A little over a hundred years ago, if you wanted hot water you heated it in a pot on a stove. Today instantly available hot running water is considered a necessity. It’s required by code at most fixture locations in most residential and commercial structures. Storage-tank type hot-water heaters provide a readily available reservoir of heated water. The simplistic design of this appliance relies on some natural characteristics of water to very efficiently move hot water throughout the plumbing system. Like air, water naturally expands and rises as it’s heated. This characteristic means that cold water entering the bottom of a tank simply pushes hot water to the top of the tank. The existing cold water pressure is all that’s required to transport hot water. A thermostat monitors the water temperature near the top of the tank and controls a source of heat at the bottom, turning this source on and off to maintain the reservoir water at a preset temperature. Although other fuels can be employed in water heaters, by far the most commonly encountered are gas and electricity. Gas heaters are typically more efficient than electric models but require a flue to expel fumes from the gas-combustion process. Gas heaters employ a burner to heat the bottom of the reservoir and, like many gas appliances, rely on a thermostatically controlled valve to allow the fuel to flow to the burner when the tanks temperature falls below a preset limit. A constantly burning smaller flame, the pilot light, ignites the main flow of gas as it reaches the burner. Recently, modern gas heaters

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contain intermittent ignition systems instead of pilot lights. This ignition system works much like the ones you’ve probably seen on an outdoor propane-fueled barbeque grill. Electric water heaters work much like gas ones except that their heat source is one or more wire elements. This element looks and functions much like the ones seen in electric cooking ovens. The thermostat at the top of the heater’s reservoir switches electrical current on and off much like the main gas valve on a gas heater controls the flow of fuel. Electric water heaters always have an element placed near the bottom of the reservoir, but some incorporate a second heating element near the reservoir’s top, speeding the time it takes to heat water (known a the recovery rate) when there’s a high demand for hot water. The efficiency of dual-element electric water heaters approaches that of gas heaters. Unlike gas water heaters, electric heaters can be safely installed in just about any location. The rest of the components installed with or in a hot-water heater relate to maintaining a safely operating system. The tendency of water to expand during can be dangerous if the water is overheated while confined in a tank. A thermostat malfunction in either an electric or gas water heater could allow the heat source to continue to operate after the tank has reached the set point temperature. The first line of defense in this case is the inclusion of a high-limit device. If the temperature exceeds the normal operating range, the high-limit device turns off the heater and requires a manual press of a reset button before the heater will restart. The second line of defense against overheating, and most important safety device in all water heaters, is the T/PRV or temperature/pressure relief valve. You learned about these valves in your last assignment. Keep in mind that even though most water heaters come with a T/PRV installed from the manufacturer, it’s the plumbers’ responsibility to connect pipe from the valve’s exhaust port to a safe location. This reduces the chance of an occupant being burned in exit in the event that the valve should open. In addition to temperature and pressure control, there are additional safety concerns related to gas-fueled water heaters. If the pilot light extinguishes in a gas heater and the main

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gas valve opens, harmful and explosive gas would soon contaminate the building. A thermocouple, a device that’s electrical characteristics change when heated, senses the presence of a burning pilot light. If the pilot isn’t sensed, the main gas valve won’t open. Rising energy costs and public interest in conservation has opened the door for new water-heating technology. Some of the energy used to heat water is wasted while the water sits in the reservoir and slowly cools. Better insulation of the tank helps reduce heat loss, but a dormant tank of heated water eventually requires reheating. Significant heat is also lost when hot water is piped over long distances to fixtures. Users then waste gallons of water running the hot water, at a sink for instance, waiting for cold water to “warm up” as the system purges the once hot (now cold water) from the pipes. Instantaneous water heaters and point-of-use units eliminate this problem by heating water at the location as it’s used and only as it’s used. They’re finding a market in both new and existing plumbing systems. The amount of energy required to heat water is directly related to the temperature of the cold supply. By raising the temperature of the incoming supply with a less expensive or renewable energy source, more scarce and expensive sources can be conserved. For instance, if using heat from the sun, the air, even the ground, increases the temperature of incoming water, then an electrical or gas heater will operate for a lower cost. After you’ve read pages 257–270 in the textbook Modern Plumbing carefully and completed the “Test Your Knowledge” on page 271, check your answers against those provided in the back of this study guide. When you’re sure that you understand the material from this lesson, complete the Lesson 4 examination.

Lesson 4

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NOTES

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Modern Plumbing, Part 1

Lesson 4 Fittings, Valves, and Heaters
EXAMINATION NUMBER

Examination Examination

15184800
Whichever method you use in submitting your exam answers to the school, you must use the number above. For the quickest test results, go to http://www.takeexamsonline.com

When you feel confident that you have mastered the material in Lesson 4, go to http://www.takeexamsonline.com and submit your answers online. If you don’t have access to the Internet, you can phone in or mail in your exam. Submit your answers for this examination as soon as you complete it. Do not wait until another examination is ready. Questions 1–20: Select the one best answer to each question.

1. Ball valves allow or prevent flow with a one-quarter turn of their handle in much the same way as _______ valves. A. gate B. flush C. ground key D. compression

2. _______ is (are) used to join two lengths of PEX tubing. A. B. C. D. Adhesive A crimping tool and rings One or more hose clamps Coupling nuts

3. The minimum-capacity gas-fired water heater, according to FHA standards, that should be installed in a home can be estimated by knowing the A. B. C. D. number of bathrooms and bedrooms. type of other heat in the building. R value of insulation in the building. type of pipes installed in the plumbing system.

95

4. Which of the following copper-pipe fittings does not cause a change in direction of flow through any of the connected pipes? A. Elbow B. Coupling C. Tee D. Drop ear elbow

5. During normal operation, water temperature is controlled in a water heater by A. a standing pilot. B. a thermostat. C. a safety shutoff. D. the tank size.

6. A _______ valve controls flow with a metal disk that slides at a right angle to the direction of water flow. A. gate B. ball
FIGURE A-6—Use this figure to answer Questions 7–8.

C. ground key D. compression

A

B

C

D

7. Which of the fittings shown in Figure A-6 is referred to as a sanitary tee? A. Fitting A B. Fitting B C. Fitting C D. Fitting D

8. Which fitting in Figure A-6 would be installed only as part of a vent system? A. Fitting A B. Fitting B C. Fitting C D. Fitting D

9. Which of the following is an advantage of a compression valve? A. B. C. D. Easy replacement of critical parts Limits water flow to one direction Unobstructed flow None of its parts ever need repair

10. The outside diameter of ABS and PVC pipe is _______ the pipe’s nominal size. A. equal to B. less than C. more than D. exactly double

96

Examination, Lesson 4

11. The buildup of _______ water in a water heater’s tank is considered a major hazard. A. superheated B. warm C. cold D. potable

12. Which of the following fixtures or appliances would contain a P/T valve? A. Toilet B. Water heater C. Urinal D. Heat pump

13. When plumbing a house prior to installation of the water meter, a plumber needs to know the A. B. C. D. meter’s capacity. safety features designed into the specific type of meter. meter’s laying length. proper method for installing the specific type of meter as this varies from one model to another.

14. The difference between a closet ell and a 90-degree ell is that the closet ell A. B. C. D. includes a cleanout. includes a reducer. includes bolt mounts for a toilet. provides a 45-degree turn.

15. When using a solar collector in a solar-assisted water-heating system, it’s typical to install A. B. C. D. two water heaters in parallel. no water heater. one storage tank feeding a water heater. a single large holding tank.
FIGURE A-7—Use this figure to answer Question 16.

16. The galvanized pipe fitting in Figure A-7 is properly identified as a A. 1 B. 1
1/ 1/ 2 2

transition union. nipple.

C. 1 D. 1

1/ 1/

2 2

reducing coupling. bushing.

Examination, Lesson 4

97

17. Local plumbing codes may prohibit water heaters that burn natural gas from being installed in the A. storage closet. B. bedroom. C. bathroom. D. basement.

18. Which of the following is not an advantage of ground key valves? A. Simplicity of design B. Unobstructed flow C. Rapid opening and closing D. Flow volume regulation

19. Plumbing codes require that a device protecting the home’s plumbing from excessive pressure be installed if the incoming municipal water pressure exceeds A. 40 psi. B. 60 psi. C. 80 psi. D. 100 psi.

20. A _______ is installed between the outlet of the flush valve and fixture to prevent back siphoning. A. circuit breaker B. diaphragm C. vacuum breaker D. plunger

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Examination, Lesson 4

Test Your Knowledge 1
1. D 3. C 4. Any three of the following: sawing, drilling, chipping, spraying, sand blasting, operation portable explosiveactivated fastening tools, welding, and the use of compressed air for cleaning 5. D 6. Any of the following: clear route, check for other people, get help with heavy or bulky objects, use slings for large pipe, keep back straight, use leg muscles, avoid contact with electrical wiring or devices 7. D 8. A 10. C 11. B 12. C 13. False 14. C 15. D 16. Ground fault circuit interrupter 17. Any three of the following: files without handles can cause puncture wounds, broken or loose hammer handles, mushroomed chisel heads, operating drilling tools can lead to hand strains, screwdrivers that slip from screw slots can injure hands, dull chisels require excessive pressure that may result in cuts. 19. B 20. Material safety data sheets provide information on each chemical in a product, including its potential hazardous effects, its physical and chemical characteristics, and recommendations for appropriate protective measures.

Answers Answers
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Test Your Knowledge 2
1. B 2. kinks 3. C 4. A 5. C 6. A vial 7. electronic 8. A 9. True 10. D 11. A 12. Any order: multispur bit, spade bit, hole saw 13. C 14. D 15. To remove the burr that might interfere with water flow 16. friction, heat 17. False 18. B 19. B 20. A 21. C 22. D

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Test Your Knowledge Answers

Test Your Knowledge 3
1. A. Tripod B. Leveling screws C. Telescope adjusting knob D. Vertical crosshair E. Horizontal crosshair 2.
1/ 4

fall per foot of run

3. 11 -5 reading at foundation 4. A 5. B 6. C 7. A 8. C 9. B 10. D

Test Your Knowledge 4
1. A. 12 B. 24 C. 36 D. 48 E. 60 F. 72 2. A. 27 B. 18 C. 54 D. 75 E. 146 F. 45

Test Your Knowledge Answers

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3. A. 1 -5 B. 3 -7 C. 4 -6 1/2 D. 7 -8 3/8 E. 2 -11 1/2 F. 1 -11 4. A. 20 B. 7 3/4 C. 11 3/4 D. 20 1/4 E. 12 7/8 5. A. 9 B. 7 1/4 C. 11 5/8 D. 14 5/8 E. 8 1/16 6. 22.63 7. 33.47 8. 11.31 9. 320 cubic feet 10. 192 cubic feet = 1436.16 gallons 11. 1004.8 cubic feet = 7515.9 gallons 12.
1/ 8

10 =

10/ 8

= 1 1/4

13. Longer. A meter is equal to 1.0936 yards. 14. Larger. A cubic inch equals 16.387 cm3 15. Smaller. A quart equals 0.946 L. 16. 100 17. 10

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Test Your Knowledge Answers

18. A. 0.457 m B. 1.22 m C. 25.4 cm D. 7.42 L E. 70.8 L F. 9.8 m3 19. A. 185°F B. 41°F C. 14°F D. 114.8°F 20. A. 40.5°C B. 7.8°C C. –31.1°C D. –11.1°C

Test Your Knowledge 5
1. D 2. A 3. B 4. B 5. D 6. A 7. C 8. D

Test Your Knowledge Answers

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Test Your Knowledge 6
1. A. Water closet, shower, lavatory B. Three C. Double D. utility and storage E. 28 -8 ? (28 -29 ) F. 12 -0 G. 2 -0 min. H. ABS plastic 2. Refer to Figure 6-13 in the text. 3. A. CI B. CO C. GAL.I D. HB E. PLBG F. WC G. WS

Test Your Knowledge 7
1. D 2. False 3. Because it’s only 50% as strong as No. 1 manila rope 4. Any order: keep the rope dry, don’t run it over sharp edges, avoid abrasion, thaw frozen rope completely before using 5. False 6. A 7. Any two of the following: double knot, short splice, long splice, single carrick bend

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Test Your Knowledge Answers

8. Any three of the following: slip knot, bowline, running bowline, eye splice, Flemish eye 9. Any three of the following: Killick hitch, timber hitch, clove hitch, slippery hitch, marlin spike hitch 10. lever hoist or winch crane, hoist standard 11. twice 12. Any two of the following: Douglas fir, spruce fir, Norway pine, aluminum, magnesium alloy, iron, steel 13. A 14. B 15. C

Test Your Knowledge 8
1. C 2. A 3. A 4. D 5. To improve the quality of plumbing codes and make them more uniform 6. B 7. C 8. Any three of the following: federal, state, and local governments, building officials, plumbers, plumbing contractors, plumbing products manufacturers, architects, and health officials 9. A 10. C 11. D 12. B

Test Your Knowledge Answers

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Test Your Knowledge 9
1. welding 2. D 3. metal, flux, heat 4. Any order: protects surface of parent metal from oxidation during heating; aids flow of filler metal; cleans joint by floating out remaining oxides; reduces surface tension of molten filler metal, which increases its wetting action 5. lead-free 6. B 7. B 8. C 9. A 10. D

Test Your Knowledge 10
1. D 2. D 3. A 4. C 5. D 6. A 7. B 8. C 9. A 10. D

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Test Your Knowledge Answers

Test Your Knowledge 11
1. A, D 2. B 3. Any order: dug, driven, drilled, bored 4. B 5. B 6. D 7. False 8. A 9. To maintain a readily available water supply at a constant pressure. 10. E 11. C 12. Place the pump in a tank of water before turning it on. 13. D

Test Your Knowledge 12
1. Any three of the following: cholera, typhoid, dysentery, gastroenteritis 2. Polio and hepatitis 3. B 4. D 5. A 6. B 7. C 8. B 9. A 10. D 11. C 12. C

Test Your Knowledge Answers

107

13. D 14. B 15. C 16. A 17. D 18. B 19. A 20. C

Test Your Knowledge 13
1. Any three of the following: one-piece molded, pedestal, built-in with metal rim, ledge type, self-rimming type 2. A 3. D 4. B 5. left 6. Any order: pressure-assisted, gravity-fed rim-jet, gravity-fed siphon-jet 7. B

Test Your Knowledge 14
1. Any order: drainage (DWV), water supply 2. False 3. acrylonitrile-butadiene styrene 4. PVC 5. Chlorinated polyvinyl chloride. It’s designed for hot water piping, but may also be used for cold water. 6. Cross-linked polyethylene 7. False

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Test Your Knowledge Answers

8. A. 90º street ell B. 90º ell with side inlet C. Sanitary tee with 90º left side outlet D. Double sanitary tee E. 45° wye F. Long-radius TY G. Offset closet flange 9. A. 90° ell B. 45º street ell C. Tee D. Copper coupling with rolled tube stop E. Copper drop tee F. Fitting adapter G. Drop ear elbow 10. B 11. True 12. K (green), L, (blue), M (red), DWV (yellow) 13. True 14. True 15. soil 16. Service (SV), extra heavy (XH) 17. B, D 18. True 19. 3, 2, 1 1/2 20. B 21. A B C 22.
1/ 2

23. Coupling

Test Your Knowledge Answers

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24. union 25. A plug closes openings in fittings 26. pipe nipples 27. Compression, flare, and inverted flare. 28.
Bill of Material
Quantity 1 8 11 5 32 2 1 1
3/ 1/ 1/ 1/ 1/ 1/ 3/ 1/ 4 2 2 2 2 2 4 2

Dimensions
1/ 1/ 2 2 1/ 1/ 2 2

Type of fitting Copper Tee Copper Tee Copper Ell Copper Cap

copper
1/ 3/ 1/ 2 4 2

1/

2

MPT

Copper Adapter Valves Valves T/P Valve

29. A. 3/4 B. 3/4 C. 3/4 D. 3/4

3/ 4 3/ 4 3/ 4 3/ 4

1/ 2 1/ 2 1/ 2 1/ 2

PVC reducing tee CPVC reducing tee copper reducing tee galvanized iron-reducing tee

Test Your Knowledge 15
1. C 2. C 3. B 4. A 5. Check valves prevent backflow of liquids or gases in piping systems. 6. D

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Test Your Knowledge Answers

7. C 8. C 9. B

Test Your Knowledge 16
1. D 2. rises, top 3. thermostat 4. T/P valve 5. False 6. B 7. B, D 8. C. Normally the lower element does all the heating. However, when large quantities of water are used, the upper heating element turns on and the lower element shuts off. 9. A. 395 pounds 10. 1803.55 pounds 11. Advantages: avoid storage loss, reduce piping costs, smaller size; Disadvantages: cost, no reservoir of hot water, low flow rates may affect temperature of water 12. Dishwasher, vacation homes, seldom used facilities 13. Larger heaters are generally gas-fired and must be vented. 14. C 15. overheat 16. Any order: insulate water pipes and water heaters, install instantaneous water heaters, solar water-heating system, heat pumps 17. They operate only when hot water is needed, and they are located near point-of-use 18. Temperature in collector must exceed storage tank temperature

Test Your Knowledge Answers

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