viii Features of the Textbook The instructional design of this textbook includes student-focused learning tools to help you succeed. This visual guide highlights these features. Chapter Opening Materials Each chapter opener contains a chapter outline, a list of learning objectives, and a list of technical terms. Objectives clearly identify the knowledge and skills to be gained when the chapter is completed. Technical Terms list the key words to be learned in the chapter. Special Features Additional features are used throughout the body of each chapter to further learning and knowledge. Procedures are highlighted throughout the textbook to provide clear instructions for hands-on service activities. Code Notes, based on the International Plumbing Code and the International Residential Code, call attention to plumbing code requirements. Safety Notes alert you to potentially dangerous materials and practices. Pro Tips provide advice and guidance that is especially applicable for on-the-job situations. Plumbing Milestones highlight the role of plumbers and plumbing in society. Illustrations Illustrations have been designed to clearly and simply communicate the specific topic. Photographic images have been updated to show the latest equipment. Expanding Your Learning Workplace Skills help you understand what you can antic- ipate and expect in the workplace. Green Notes highlight key items related to sustainability, energy efficiency, and environmental issues. Copyright Goodheart-Willcox Co., Inc. 101 C H A P T ER 6 Mathematics for Plumbers OBJECTIVES After studying this chapter, you will be able to: ■ Read a rule accurately to the nearest 1/16″. ■ Add and subtract fractions and whole numbers. ■ Compute pipe offsets using the Pythagorean theorem and trigonometric functions. ■ Apply the formulas for finding area and volume. ■ Compute the total slope of a run of drainpipe. ■ Explain and apply SI metric measure in finding length, area, volume, and temperature. ■ Convert customary measure to metric measure. TECHNICAL TERMS laying length plumber’s rule Pythagorean theorem trigonometric functions Pume lumbers need to make accurate measurements and calculations. They need to add and subtract dimensions, compute pipe offsets, and determine the vol- of tanks. This chapter provides the basic information needed to master these skills. In addition, metric measurement is introduced. Workplace Skills Helping a New Team Member Your company obtained a major contract to install the plumbing system for a dozen homes being built in a new subdivision. You are assigned to work with a new team of four people to install the DWV piping in these homes. One person assigned to the team is a new employee who previously worked for a concrete company. At the jobsite, the supervisor walks the team through the building, indicating where DWV piping should be installed on the first floor. The supervisor instructs you and the new team member to move tools and materials from the truck into the house, set up lights on the first floor, add a set of lights in the basement, and bring select- ed tools and materials to the basement and first floor. What can you do to help the new employee feel part of the How should you handle questions that arise? What do you do if the new employee does something that is incorrect or dangerous? These suggestions should help. ■ Suggest a location where the two of you can safely store your food. ■ As you take lights to the basement and first floor, consider what routes will be best for moving tools and materials into the desired location. For example, it may be easier for one of you to hand ten-foot lengths of pipe through a window opening. ■ Check the route you are going to use to avoid hazardous situations. ■ Ask the new employee about their previous work experience. ■ Get to know the new employee. Try talking about hobbies, family, or sports. Respond to the following questions: ■ What can you do to encourage the new employee? ■ What can you share about the plumbing company with your coworker? ■ How would you help the new employee stop rushing and risking injury? ■ What you do if the new employee is not getting enough work done? Copyright Goodheart-Willcox Co., Inc. Chapter 11 Soldering, Brazing, and Welding 155 Plumbers generally prefer 1/8″ solid-core solder that is sold in one-pound spools. These solders should be used only where pipe temperatures will not exceed 250°F (121°C). They are generally suited to low-pressure steam applications, as well. Hard solders are composed of various percentages of copper and zinc alloys. They are used in the brazing of cast iron, iron, steel, brass, and sometimes copper. 11.1.2 Fluxes Flux is a chemical substance that prevents oxides from forming on the surface of metals as they are heated for soldering, brazing, or welding. Soldering flux performs several functions: ■It protects the surface from oxidation during heating. Oxidation is the process of picking up oxygen that produces tarnish and rust in metals. ■It helps the filler metal flow easily into the joint. ■ It floats out remaining oxides ahead of the molten solder. ■It increases the wetting action of solder by lowering the surface tension of the molten metal. Highly corrosive fluxes contain inorganic acids and salts such as zinc chloride, ammonium chloride, so- dium chloride, potassium chloride, hydrochloric acid, and hydrofluoric acid. Less corrosive fluxes contain milder acids such as cit-430 ric acid, lactic acid, and benzoic acid. Although they are briefly very active at soldering temperatures, their cor- rosive elements are driven off by the heat. Residue does not remain active and is easily removed after the joint is cool. Noncorrosive fluxes, the only type suited for plumb- ing work, are composed of water and white resin dis- solved in an organic or benzoic acid. The residue does not cause corrosion. These fluxes are effective on copper, Code Note IRC Note Standards for fittings, soldering flux, and brazing flux are given in Chapter 29 of the IRC. This part of the code also indicates the limited amount of lead permitted in solder and fluxes. brass, bronze, nickel, and silver. Noncorrosive fluxes are recommended for joining copper pipe and fittings. The best fluxes for joining copper pipe and fittings are compounds containing mild concentrations of zinc and ammonium chloride. These cleaning agents are mixed with a petroleum base to produce a noncorrocan- sive paste that is easily applied. Composition Soldering Temperature Range (team? °F) Tin (%) Antimony (%) Copper (%) Silver (%) 95 96 95.5 94 5 4 4 0.5 6 430–480 430–450 440–500 430–550 Goodheart-Willcox Publisher Figure 11-1. The composition and recommended soldering temperature for lead-free solder. P R O C E D U R E Soldering Procedure Soldering is not difficult. Each operation, however, must be performed carefully for satisfactory results. Carefully study the following procedures before attempting to make a solder joint: 1. Cut the copper pipe with a tubing cutter, Figure 11-2. 2. Ream the ends of each pipe to remove metal burrs, Figure 11-3. 3. Cleaning is a very important part of making good solder joints. Use a fitting brush, tube brush, abrasive paper, emery cloth, or steel wool, Figure 11-4, to clean the copper pipe ends and the socket or cup of the fitting. Do a thorough job. After the scale and dirt are removed, brush away any loose abrasive particles. Avoid touching the clean metal with your fingers. 4. Immediately apply the proper flux to all pipe and joint areas to be soldered with a clean brush, as shown in Figure 11-5. It is important to apply flux soon after the joint is cleaned. Otherwise, the copper begins to oxidize and the oxide inhibits the soldering process. Continued A B Wheeler Mfg. Co. Figure 11-2. A tubing cutter produces a square cut that needs little dressing. A—Standard tubing cutter. B—Small tubing cutter for use in tight spaces. Wheeler Mfg. Co. Figure 11-3. A reamer is used to remove the wire edge or burrs formed on the inside of copper tubing during cutting. Copyright Goodheart-Willcox Co., Inc. Section 3 Plumbing System Design and Installation units must be drained, a hose can be attached and the water directed outside or into a floor drain. The same may be true for smaller swimming pools. Large spas and swimming pools, however, are likely to require di- rect connection to the plumbing system. 28.1 Design Considerations The design and installation of swimming pools, hot tubs, and spas are regulated to provide for the public health and safety. In most communities, the health department is responsible for inspecting and approv- ing these installations. The code requirements for these facilities vary somewhat. For a particular instal- lation, it will be necessary to contact local officials to learn specific requirements. Code Note IPC Note IPC does not cover swimming pools. IPC is compatible with the ISPSC. ISPSC is available for adoption by local building officials. Notes in this chapter about ISPSC regulations are labeled ISPSC Note. Plumbing Milestone The ancient Roman baths were primarily large aquatic recreational facilities, where hundreds of citizens at a time could relax, soak, and socialize. Personal hygiene was a secondary function. The primary considerations when selecting pumps and filters include the capacity of the hot tub or pool, the bathing load, and the turnover rate. The capacity of a tub or pool is the amount of water it holds, measured in gallons. The bathing load is the maximum number of people who will use the facility per hour. The turnover rate is the frequency with which the total volume of water in the tub or pool is circulated through the filter. Figure 28-1 Green Note Solar and Geothermal Water Heating Heating outdoor swimming pools, hot tubs, and spas extends the number of days they can be used each year. Using solar or geothermal heating systems reduces the amount of energy required for heating. Solar systems are like the solar water heating systems discussed in Chapter 18. The water in the pool, hot tub, or spa is pumped through the collectors where it is heated before returning to the pool, hot tub, or spa. The only energy required to operate the system is for the pump motor and controls. The major disadvantage of solar systems is that sunlight is necessary for them to function. Geothermal systems are essentially heat pumps that collect heat from the earth and transfer it to the water in the pool, hot tub, or spa. These systems use refrigerant to collect heat. Compressing the refrigerant increases its temperature before it enters a heat exchanger where the heat is transferred to the water from the pool, hot tub, or spa. The energy requirement for these systems is limited to running electric motors for pumps and operating the controls for the system. A major advantage of geother- mal systems is that heat can be collected from the earth 24 hours a day. Capacity (gallons) Turnover* gpm (gallons per minute) Bathing load per hour† at a given turnover 6 hr 8 hr 10 hr 12 hr 6 hr (225 gal) 8 hr (400 gal) 10 hr (625 gal) 12 hr (900 gal) 31,600 38,400 55,500 80,900 119,500 158,700 207,600 254,300 305,700 422,400 557,600be 632,100 703,900 883,000code 1,074,900 88 105 155 225 335 440 575pumps 710 850of 1,170 1,550The 1,750 1,950 2,450 2,990in 66 80 115 170 250 330 435installed 530 640the 880 1,160 1,320asubstitute 1,465 1,840 2,240extremely 53 92 135 200 265 345 425 705 1,055 1,170 1,795 44 54 77 115 165 220 290 355 425 585 775 880 975 1,225 1,495 23 23 40 60 89 117 154 188 226 314 413 468 521 654 796 10 12 17 25 37 50 65 80 96 133 179 197 220 276 336 5 6 9 13 19 25 33 41 49 68 89 101 112 142 172 3 4 5 7 11 15 19 24 28 38 52 58 65 82 99 *Turnover or refiltratation rate to nearest 5 gpm except when rate is less than 100 gpm. †Bathing load per hour based on refiltration rate indicated. For daily bathing load, multiply by hours in operating day. Josam Manufacturing Co. Figure 28-1. Sizing of pumps and filters is directly related to the water capacity and bathing load. Copyright Goodheart-Willcox Co., Inc. Chapter 13 Water Supply Systems 18764 13.4 Pump Installation Local codes may require that be by licensed workers. Regardless who does instal510 - lation, however, local code and the manufacturer’s instructions should followed. following are gen930 - eral suggestions and are not intended to be for either the local or manufacturer’s directions.1,470 The depth of the components the well is important. If they are set all the way to the bottom of the well casing, it is likely that sediment will clog the screen and that the pump will wear excessively. On the other hand, if the pump or end of the drop pipe is too high in the groundwater, the well may be unable to recover fast enough to supply the needed water. The total depth of the well and the typical drawdown can be used to deter- mine the correct depth of the drop pipe or pump. If the water-bearing layer is sand or other fine mate- rial, it will be essential to select an appropriate screen to prevent this material from entering the pump. 13.4.1 Deep-Well Jet Pump Installation As described earlier in this chapter, most deep-well jet pumps are installed using two pipes inside the well casing. When the casing is small, it is possible to utilize a packer-type ejector, Figure 13-19, which converts the well casing into the pressure pipe. The well cas- ing adapter seals the casing at the top and provides an attachment for the pressure outlet from the pump. The compressed air passes to the inside of the sealed casing around the outside of the drop pipe. Check valve Helical rotor Drive cable Motor Rubber stator Goodheart-Willcox Publisher Figure 13-17. A deep-well helical pump has the motor mounted aboveground. Molded rubber stator Motor Inlet Helical rotor Goodheart-Willcox Publisher Figure 13-18. Submersible deep-well helical pumps place the motor in the well. Well casing adapter Two- pipe ejector Packer- type ejector Water Systems Council Figure 13-19. A one-pipe jet pump system uses a packer- type ejector.