Quiz 02_ CH07 - CH08_ Refrigeration Fundamentals PDF

10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Quiz 02: CH07 - CH08 Due Oct 7 at 11:59pm Points 75 Questions 75 Available Sep 30 at 12am -...

10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Quiz 02: CH07 - CH08 Due Oct 7 at 11:59pm Points 75 Questions 75 Available Sep 30 at 12am - Oct 7 at 11:59pm Time Limit None This quiz was locked Oct 7 at 11:59pm. Attempt History Attempt Time Score LATEST Attempt 1 187 minutes 53 out of 75 * * Some questions not yet graded Score for this quiz: 53 out of 75 * * Some questions not yet graded Submitted Oct 6 at 7:25pm This attempt took 187 minutes.  Question 1 0 / 1 pts If a technician needed 5/8" ACR for an installation and was located near only a plumbing supply house, what size and type of pipe should he ask for? You Answered 5/8" ACR. 1/2" PVC. Correct Answer 1/2" ID Copper. 5/8" PVC.  Question 2 1 / 1 pts The size indicated for the diameter of copper tubing used for plumbing is the ____. Correct! https://peralta.instructure.com/courses/73221/quizzes/373528 1/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 inside diameter outside diameter wall thickness None of the above.  Question 3 1 / 1 pts The size indicated for the diameter of ACR copper tubing is the ____. inside diameter Correct! outside diameter wall thickness None of the above.  Question 4 1 / 1 pts The maximum temperature at which soft soldering is done is ____. 212°F 400°F 600°F Correct! 842°F  Question 5 1 / 1 pts When soldering or brazing, the solder is ____. heated directly by the flame of the heat source heated by the surrounding air used to oxidize the metal Correct! melted by heat from the tubing and fitting  Question 6 1 / 1 pts https://peralta.instructure.com/courses/73221/quizzes/373528 2/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Filler materials used in the high temperature connection of copper joints are composed of ____. 50/50 tin-lead 95/5 tin-antimony Correct! 15%-60% silver bronze  Question 7 1 / 1 pts Molten solder flows between the two base metals being soldered because ____. the atmospheric pressure pushes it in Correct! of capillary attraction there are no surface pores in the base metal the tubing surface melts and the pressure differential forces it in  Question 8 1 / 1 pts The proper type of flame from an oxyacetylene torch for silver brazing is ____. long tail flame Correct! neutral flame oxidizing flame carbonizing flame  Question 9 0 / 1 pts When soldering, why should flux be used? You Answered It helps prevent oxidation. It helps keep pipes clean. It helps solder flow easier. Correct Answer All of the above are correct. https://peralta.instructure.com/courses/73221/quizzes/373528 3/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570  Question 10 1 / 1 pts When soldering, flux should be applied to ____. Correct! the male part of the joint only the female part of the joint only both the male and female parts of the joint around the mated parts  Question 11 1 / 1 pts For cleaning ACR copper tubing before soldering, a material that can be used is ____. steel wool carborundum cloth Correct! sand cloth nylon wool  Question 12 1 / 1 pts Pipe threads are standardized by the A.N.S. A.N.S. stands for ____. All Nominal Standard Correct! American National Standard All New Steel Apparent Nominal Standard  Question 13 1 / 1 pts Pipe threads, when used on pipe that will contain liquid or vapor under pressure, ____. are tapered should have at least seven perfect threads generally have a "V" shape https://peralta.instructure.com/courses/73221/quizzes/373528 4/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Correct! All of the above.  Question 14 1 / 1 pts When joining steel pipe, a ____ should be applied to the threads before connecting. Correct! pipe dope flux solder gasket  Question 15 1 / 1 pts K-type copper is heavy duty with a thick tubing wall. Correct! True False  Question 16 1 / 1 pts L-type copper is considered medium weight and is used most frequently. Correct! True False  Question 17 1 / 1 pts M is a lightweight copper and is not commonly used in our industry. Correct! True False  https://peralta.instructure.com/courses/73221/quizzes/373528 5/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Question 18 1 / 1 pts DWV copper stands for drain, waste and vent and is also a lightweight copper not typically used in the HVACR industry as far as refrigerant-carrying applications are concerned. Correct! True False  Question 19 1 / 1 pts When tubing is cut with a tubing cutter, a burr is produced in the process. This slight decrease in the inside diameter of the tube can adversely affect the operation of the system. Correct! True False  Question 20 1 / 1 pts When installing a refrigeration system, the piping should be connected with as few joints as possible. Correct! True False  Question 21 1 / 1 pts When soldering, the technician should heat the solder with the torch to allow it to melt. True Correct! False  Question 22 1 / 1 pts 95/5 tin-antimony solder can be used in any part of a refrigeration system. True Correct! https://peralta.instructure.com/courses/73221/quizzes/373528 6/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 False  Question 23 1 / 1 pts An air-acetylene unit usually consists of a B tank of acetylene gas, a regulator, a hose, and a torch. Correct! True False  Question 24 1 / 1 pts The use of flux is always required when soldering or brazing. True Correct! False  Question 25 1 / 1 pts ABS and PVC pipe can be used to carry the new blended refrigerants in low temperature applications. True Correct! False  Question 26 0 / 1 pts The copper tubing used in the field piping of refrigeration systems is type ____________________. You Answered air-conditioning and refrigeration (ACR) Correct Answers ACR  Question 27 0 / 1 pts The tubing or pipe for natural gas supply to a gas heating unit is ____________________. https://peralta.instructure.com/courses/73221/quizzes/373528 7/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 You Answered steel pipe Correct Answers steel wrought iron  Question 28 1 / 1 pts One reason for insulation on a suction line is to help maintain the proper ____________________. Correct! temperature Correct Answers temperature  Question 29 0 / 1 pts Four tools that are needed to properly prepare and thread steel pipe are the pipe cutter, reamer, threader, and ____________________. You Answered holding tools Correct Answers vise  Question 30 1 / 1 pts In order to thread steel pipe, ____________________ is applied so friction and heat do not damage the pipe and/or cutting dies. Correct! cutting oil Correct Answers cutting oil https://peralta.instructure.com/courses/73221/quizzes/373528 8/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570  Question 31 1 / 1 pts In the thread specification 1/2-14 NPT, the 1/2 is the ____________________. Correct! thread diameter Correct Answers thread diameter  Question 32 0 / 1 pts In the thread specification 1/2-14 NPT, the 14 stands for ____________________. You Answered number of threads per inch Correct Answers threads per inch  Question 33 1 / 1 pts In the thread specification 1/2-14 NPT, the NPT stands for ____________________. Correct! national pipe taper Correct Answers National Pipe Taper  Question 34 1 / 1 pts The abbreviation for the plastic pipe used in systems for water drains, waste drains, and low-temperature vents is ____________________. Correct! ABS https://peralta.instructure.com/courses/73221/quizzes/373528 9/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Correct Answers ABS  Question 35 1 / 1 pts The abbreviation for the plastic pipe used in systems for water and gas supply lines and irrigation systems is ____________________. Correct! PE Correct Answers PE  Question 36 1 / 1 pts The abbreviation for the plastic pipe used in high pressure systems at low temperature is ____________________. Correct! PVC Correct Answers PVC  Question 37 1 / 1 pts The abbreviation for the plastic pipe used in hot and cold water supply systems is ____________________. Correct! CPVC Correct Answers CPVC  Question 38 Not yet graded / 1 pts Why should some refrigerant lines be insulated? https://peralta.instructure.com/courses/73221/quizzes/373528 10/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Your Answer: When the piping is exposed to the ambient air it can transfer heat energy from the environment into the tubing and refrigerant. You want to avoid absorbing external heat in the suction line since it would make the compressor work harder. Essentially, insulation helps to prevent heat transfer from the outside ambient air into your refrigeration system.  Question 39 Not yet graded / 1 pts What are two purposes for using insulation on the suction line? Your Answer: Insulating the suction line prevents heat transfer into your refrigeration system so that the refrigerant is a low-pressure, superheated vapor when it reaches the compressor and so that condensation/frosting does not form on your suction line.  Question 40 Not yet graded / 1 pts When soldering, by what force, the molten filler material flows between the two base metals? Your Answer: Via capillary action  Question 41 Not yet graded / 1 pts When making a swage joint, what should the depth of the enlarged portion of the tube be? Your Answer: The depth of the enlarged portion should be about the same length as the outside diameter of the tubing.  Question 42 Not yet graded / 1 pts The type of steel pipe thread used primarily in this industry is the "tapered" thread. Why? Your Answer: https://peralta.instructure.com/courses/73221/quizzes/373528 11/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Tapered threads are used because they produce a tight joint that prevents leakage of fluids (water, gas).  Question 43 1 / 1 pts Match the term with its definition Correct! Operation that causes one end of a copper tube to expand at an angle for flare nut connection to system. flaring Correct! Operation of heating and cooling tubing to make it softer. annealing Correct! Accomplished at temperatures under 842°F. soldering Correct! Removal of burrs and rough edges from tubing. reaming Correct! Accomplished at temperatures above 842°F. brazing Correct! Caused by excessive bending and straightening of tubing. work hardening https://peralta.instructure.com/courses/73221/quizzes/373528 12/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Correct! Operation that allows two tubes of equal diameter to be joined together. swaging  Question 44 1 / 1 pts When moisture is present in a refrigeration system, it will react with the refrigerant and the oil to form ____. carbon dioxide Correct! acid carbon monoxide carbolic acid  Question 45 1 / 1 pts Noncondensable gases ____. are desirable in a refrigeration system Correct! are undesirable in a refrigeration system condense readily under normal atmospheric conditions help in pulling a vacuum  Question 46 1 / 1 pts To pull a vacuum means to ____. raise the pressure in a refrigeration system Correct! lower the pressure in a refrigeration system below atmospheric allow refrigerant to escape into the atmosphere condense the gas in the system  https://peralta.instructure.com/courses/73221/quizzes/373528 13/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Question 47 1 / 1 pts A compound gauge ____. indicates pressures above 14.696 psia indicates pressures in inches Hg below atmospheric pressure is one of two gauges on a typical gauge manifold Correct! All of the above.  Question 48 1 / 1 pts A micron gauge is used to measure ____. atmospheric pressures at high altitudes atmospheric pressures at sea level Correct! absolute pressures below 1 mm Hg high pressure in a refrigeration system  Question 49 1 / 1 pts At what pressure range does the technician valve off the vacuum pump when evacuating to a deep vacuum? 200 to 100 microns. 300 to 100 microns. 300 to 200 microns. Correct! 500 to 300 microns.  Question 50 1 / 1 pts Which of the following represents the lowest vacuum? 10 psia. 5 in. Hg vacuum. 5 psig. https://peralta.instructure.com/courses/73221/quizzes/373528 14/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Correct! 1000 microns.  Question 51 1 / 1 pts A multiple evacuation means that ____. you connect three vacuum pumps simultaneously to a refrigeration system and pull a vacuum you pull a vacuum on three different systems at the same time Correct! you pull a vacuum on a refrigeration system more than once, allowing refrigerant or nitrogen into the system between each procedure there must be more than one system operating before a vacuum can be pulled  Question 52 1 / 1 pts Moisture in a liquid state must be ____ before it can be removed with a vacuum pump. Correct! vaporized condensed cooled solidified  Question 53 0 / 1 pts To insure accurate testing, the best material to use for connecting lines to the vacuum pump and gauge set is ____. light flexible hose You Answered heavy duty rubber gauge line Correct Answer copper tube garden hose  https://peralta.instructure.com/courses/73221/quizzes/373528 15/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Question 54 1 / 1 pts The maximum recommended pressure for leak testing is 150 psig on the low-pressure side of the system. Correct! True False  Question 55 1 / 1 pts Air entering a refrigerant system can eventually lead to compressor failure. Correct! True False  Question 56 1 / 1 pts Clearance tolerances are such that the ordinary clean refrigerant oil can be used satisfactorily in a vacuum pump. True Correct! False  Question 57 0 / 1 pts The oil in a vacuum pump should be changed after each time it is used. Correct Answer True You Answered False  Question 58 1 / 1 pts While under a deep vacuum, any liquid water under the oil in the motor-compressor assembly can be removed by operating the compressor motor for several seconds without any adverse effect on the system. True https://peralta.instructure.com/courses/73221/quizzes/373528 16/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Correct! False  Question 59 1 / 1 pts After repairing a system that has had an electrical motor failure (compressor burnout), it is good field practice to re-use the recovered refrigerant in that system. True Correct! False  Question 60 0 / 1 pts When using a "standing pressure test" for leak-checking, ____________________ should never be used since an explosive mixture can be created. You Answered halide leak detector Correct Answers air  Question 61 1 / 1 pts Sludge is produced when moisture, acid, and ____________________ are present in the system. Correct! oil Correct Answers oil  Question 62 1 / 1 pts Only two substances should be in the refrigeration system for proper operation. They are ____________________ and oil. Correct! https://peralta.instructure.com/courses/73221/quizzes/373528 17/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 refrigerant Correct Answers refrigerant  Question 63 1 / 1 pts Micron gauge displays can be electronic analog, digital, or ____________________. Correct! light-emitting diode Correct Answers light-emitting diode (LED) light-emitting diode LED  Question 64 1 / 1 pts The electronic vacuum gage is attached to the system so it can measure the pressure ____________________ the system. Correct! inside Correct Answers inside  Question 65 1 / 1 pts There are ____________________ microns in 1 mm Hg. Correct! 1000 Correct Answers 1000 1,000 https://peralta.instructure.com/courses/73221/quizzes/373528 18/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 one thousand  Question 66 1 / 1 pts A(n) ____________________ pressure could also mean refrigerant vapor is still seeping from the refrigeration system. Correct! rising Correct Answers rising  Question 67 1 / 1 pts A deep vacuum involves reducing the pressure in a refrigeration system to a micron gauge reading of ____________________ or below. Correct! 500 Correct Answers 500 five hundred  Question 68 Not yet graded / 1 pts Why is refrigerant not used for a system standing pressure test? Your Answer: I would think that refrigerant is not used because there are environmental concerns around using refrigerant that might leak out of a potential leak and refrigerants might not operate at the same pressure as gases like dry nitrogen.  Question 69 Not yet graded / 1 pts Why is nitrogen considered a "noncondensable" gas? Your Answer: https://peralta.instructure.com/courses/73221/quizzes/373528 19/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Nitrogen stays in a gaseous state throughout the refrigeration system and does not condense into a liquid because it has a low boiling point and can stay in a gaseous form even at the temperatures and pressures within a refrigeration system.  Question 70 Not yet graded / 1 pts A pressure of 100 microns has been reached with the vacuum pump operating. The pump is turned off and the gauge reading rises to 500 microns and stays there. What does this indicate? Your Answer: Well, this might just mean that the reading is stabilizing. You are looking for a reading at or below 500 microns (deep vacuum) so the system most likely does not have leaks or moisture if it stays at 500 microns and does not increase from that reading.  Question 71 Not yet graded / 1 pts A pressure of 100 microns has been reached with the vacuum pump operating. The pump is turned off and the gauge reading rises to 5,000 microns and stays there. What does this indicate? Your Answer: If the pressure reading on the micron gauge increases and then stays at 5000 microns then it might mean that there is moisture in the system and it is boiling which is then increasing the pressure reading.  Question 72 Not yet graded / 1 pts A pressure of 100 microns has been reached with the vacuum pump operating. The pump is turned off and the gauge reading rises above 5,000 microns and keeps rising. What does this indicate? Your Answer: If the pressure reading on the micron gauge increases to 5000 microns and keeps rising then it might mean that there is a leak in the system and gases from outside are entering the refrigeration system which is then increasing the pressure reading.  Question 73 Not yet graded / 1 pts https://peralta.instructure.com/courses/73221/quizzes/373528 20/21 10/14/24, 10:21 AM Quiz 02: CH07 - CH08: ECT-13-Fundamentals of Refrigeration-L1-41570 Why must all valves be opened when an evacuation is performed? Your Answer: Valves must be opened because you want less resistance to flow during an evacuation process and you want to make sure all parts of the system are vacuumed and that noncondensables or moisture is completely removed from the system.  Question 74 Not yet graded / 1 pts Explain why triple evacuations are not normally performed on large systems. Your Answer: The triple evacuation process would take a lot of time on a large system, so it would not be efficient to take that approach.  Question 75 Not yet graded / 1 pts Why is it a good idea to remove Schrader stems from service valves prior to evacuation? Your Answer: It is a good idea to remove Schrader stems before evacuation because you want to reduce the resistance to flow that the Schrader valve will cause in the stem. Quiz Score: 53 out of 75 * Some questions not yet graded https://peralta.instructure.com/courses/73221/quizzes/373528 21/21