Pass Benchmark: 70% (21/30) • Standard: USCG NMC / 46 CFR

USCG Refrigeration & Air Conditioning (Set 3)

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Question 1 of 30

A device used to hold open the refrigeration compressor suction valve during starting to reduce the compression load is called what?

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30 MCQs

#1 A device used to hold open the refrigeration compressor suction valve during starting to reduce the compression load is called what? #2 Refrigeration systems using forced air circulation evaporators have a tendency to cause rapid dehydration of produce in chill boxes. Which of the following will minimize this dehydration? #3 If a condenser coil of an air-cooled container refrigeration system becomes dirty and requires cleaning, what would be an acceptable method of cleaning? #4 For safe storage, the maximum allowable temperature to which refrigerant bottles should be exposed is what temperature? #5 Personnel servicing refrigeration systems and subject to the exposure to commonly used refrigerants should wear what type of personal protective equipment? #6 Which of the precautions listed should be taken before opening any part of a refrigeration system for the purpose of accomplishing non-major repairs? #7 Why can CFC or HCFC refrigerants leaking into a confined space or in limited surroundings cause suffocation? #8 Overfilling a refrigerant container is extremely dangerous because of the high pressures generated. The generation of pressure is the result of what? #9 Traditionally, which of the listed refrigerants has been more suitable than the others for use in a centrifugal refrigeration compressor? #10 Which of the fluids listed is suitable for use as a secondary refrigerant? #11 The amount of HCFC-123 in a storage cylinder is measured by what means? #12 The gas that exists in the stratosphere forming a protective shield that helps to protect the environment from the harmful effects ultraviolet radiation is called what? #13 The "tare weight" of a refrigerant storage cylinder refers to what weight? #14 The term 'oil foaming' in refrigeration practice, is used to describe what event? #15 What is the physical state and pressure condition of refrigerant as it enters the condenser of a typical refrigeration system? #16 What is the physical state and pressure condition of refrigerant as it leaves a receiver in a typical refrigeration system? #17 What is the pressure and condition of the refrigerant entering the receiver of a refrigeration system? #18 The safety heads of most large reciprocating compressors used in refrigeration systems are held in place by what means? #19 A device used to hold open the refrigeration compressor suction valve during starting to reduce the compression load is called what? #20 The carbon seal ring of a refrigeration compressor crankshaft mechanical seal is held in position against the stationary ring face by using what device? #21 If the discharge reed valves used in a refrigeration compressor are leaking badly, what statement is true? #22 In addition to the drive belt itself, a V-belt that is tensioned too tight will cause excessive wear to what other drive component? #23 When one belt of a multiple V-belt drive requires replacing, what will be required? #24 Excessively tight drive belts installed between a motor and a refrigeration compressor pulley may cause what condition? #25 When installing a mechanical shaft seal on a refrigeration compressor, extreme care must be taken to prevent what from happening? #26 A reciprocating refrigeration compressor may be tested for leaking discharge valves by stopping the compressor, turning the discharge service valve all the way in, and then turning the compressor over by hand. If the discharge valves are leaking, the compound gage will show pressures which react in which way? #27 Unusual noise coming from a refrigeration compressor can be caused by which of the following conditions? #28 Which of the listed statements describes the reason why oil foaming occurs when starting a refrigeration compressor? #29 Leaking suction valves in a refrigeration compressor are indicated by which of the following? #30 Why are dehydrators usually located in the liquid line of refrigeration systems?

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