Pass Benchmark: 70% • Standard: USCG NMC / 46 CFR
USCG Engine Refrigeration (Supplementary) (Set 2)
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Question 1 of 30
The most cost-effective method of recovering refrigerant from a low pressure chiller with more than 500 lbs of refrigerant and to meet EPA requirements is to recover the refrigerant using what protocol?
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30 MCQs #1 The most cost-effective method of recovering refrigerant from a low pressure chiller with more than 500 lbs of refrigerant and to meet EPA requirements is to recover the refrigerant using what protocol? #2 Why is a purge recovery unit typically fitted on low pressure centrifugal chillers? #3 As shown in the illustrated flow diagram for a self-contained recovery unit designed for the recovery of refrigerants from high pressure appliances as defined by the EPA Clean Air Act rules, what is the functional purpose of the item labeled "FS2"? GS-RA-32
Illustration GS-RA-32: the U.S. Coast Guard has not released this illustration. #4 Concerning frost appearing on one set of evaporator coils of a multi-box, direct expansion type refrigeration system, what is true? #5 Some 'hot gas' defrost systems reheat the refrigerant just prior to its returning to the compressor for what purpose? #6 What is the maximum volume to which refillable refrigeration cylinders should be filled? #7 The pressure in the part of a high pressure refrigeration system about to be opened for a non-major repair should be brought to what value? #8 The primary purpose of the liquid line strainer used in a refrigeration system is to prevent dirt and scale from entering what system component(s)? #9 Of the various possible methods shown in the illustration, which is the correct method of attaching a TXV feeler bulb to a small large line (7/8" and larger) with a horizontal run? GS-RA-50
Illustration GS-RA-50: the U.S. Coast Guard has not released this illustration. #10 A thermostatic expansion valve is properly controlling evaporator superheat. Adjusting this valve to lower the evaporator superheat setting will result in which of the following? #11 An evaporator coil of a single evaporator, air cooled refrigerator is accumulating excessive frost due to a failure of the defrost mechanism. If the refrigerator features a thermostatically controlled box solenoid and a low pressure cutout controlled compressor, as well as a high pressure cutout, in terms of the compressor, what would be the most likely operating symptom? #12 What must be done to use standard leak detection methods on a low pressure refrigeration system charged with refrigerant? #13 What is a quick method used to test a water cooled condenser for the presence of a refrigerant leak without actually pinpointing the actual location? #14 Excessive moisture being collected in the purge unit of a low pressure refrigeration system could indicate which probable condition? #15 Moisture entering a typical refrigeration system will most likely produce what effect? #16 High suction pressure accompanied by low suction temperature to a refrigeration system compressor is caused by which of the following? #17 Which of the conditions listed could cause excessively low refrigerant pressure at the compressor suction of a TXV controlled refrigeration system? #18 Low compressor head pressure in a refrigeration system can be caused by which of the following? #19 Which of the following conditions will occur if the power element of the thermostatic expansion valve shown in the illustration loses its charge? GS-RA-07
Illustration GS-RA-07: the U.S. Coast Guard has not released this illustration. #20 You are checking the supply chilled water temperature thermistor probe on a high- pressure hermetic centrifugal chiller. Using the illustrated chart, what statement is true if the supply water temperature is verified 45 ° F with a digital thermometer? GS-RA-48
Illustration GS-RA-48: the U.S. Coast Guard has not released this illustration. #21 Some refrigeration systems have chemical moisture indicators installed in conjunction with the sight glass in the liquid line. If excess moisture is present in the system, how will a typical moisture indicator respond? #22 If a liquid drying agent is used in a refrigeration system already equipped with a solid drying agent, the liquid drying agent will cause what type of reaction? #23 The fluid used as a source of actuating power against the underside of the unloader power element piston of the refrigeration compressor capacity control mechanism illustrated is obtained from where? GS-RA-13
Illustration GS-RA-13: the U.S. Coast Guard has not released this illustration. #24 During operating periods of a multi-box refrigeration system using a capacity controlled compressor, when all of the evaporators of a four box plant are actively being fed with liquid refrigerant, the control oil pressure acting on the hydraulic relay piston will be at what value? GS-RA-13
Illustration GS-RA-13: the U.S. Coast Guard has not released this illustration. #25 To prevent motor overload during start-up of a hermetically sealed centrifugal refrigeration system, what is true concerning the compressor suction gas variable inlet guide vanes? #26 A box solenoid valve used in a multi-box refrigeration system is operated by electro- magnetic action by what control device? #27 A liquid line solenoid valve controls refrigerant flow to the evaporator by what means? #28 As shown in the illustrated refrigeration system piping schematic diagram with the various accessories and controls and equipped with an air-cooled condenser with high side pressure controls, what statement is true concerning the fan cycling control pressure switch? GS-RA-39
Illustration GS-RA-39: the U.S. Coast Guard has not released this illustration. #29 If it is necessary to increase the operating head pressure of the refrigeration system using the device shown in the illustration, what should be done? GS-RA-14
Illustration GS-RA-14: the U.S. Coast Guard has not released this illustration. #30 In a refrigeration system, the valve shown in the illustration is used for what purpose? GS-RA-14
Illustration GS-RA-14: the U.S. Coast Guard has not released this illustration.
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