Fdny Z-51 Refrigeration: Test Exam Questions Guarenteed Success.lqtest Updates 2024/2024.(200 Questions Allready Passed)

FDNY Z-51 REFRIGERATION: TEST EXAM QUESTIONS GUARENTEED SUCCESS.LQTEST UPDATES 2024/2024.(200 QUESTIONS ALLREADY PASSED) The efficiency of the refrigerant cycle is affected by the operation of the condenser. of the following. a more efficient centrifugal compressor operation results from: - answers Lowering the condensing pressure The heat removed from the refrigerant in a condenser is: - answers Sensible and latent heat The refrigerant unit that you have been assigned to is being taken out of service for a major repair. you have been assigned to withdraw refrigerant for storage in suitable containers. according to the new York city fire code, you must ensure that the containers: - answers Are approved by the US department of transportation Which of the following best describes how the cylinder unloader work? - answers Keep in the suction valve opened while the compressor is in the return stroke In most semi hermetic compressors, the suction vapor is used to: - answers Cool the motor The amount of refrigerant that flows through the orifices of a economizer is determined by the: - answers Difference between the high side and load side pressure The installation of an inline refrigerant cleaning system is advisable: - answers To remove impurities from the system The type of refrigerant system that is least likely to leak refrigerant into the building space that are cooled - answers The indirect system The suction pressure of a reciprocating compressor is 65PSIG. the discharge pressure of this compressor is 120PSIG. the atmospheric is 14.7 PSI. the compression ratio for the given condition is closet to: - answers 1.69 A super heated vapor is a ? - answers Dry vapor above the saturation temperature A refrigerant engineer verifies that a condenser water pump is cavitating. of the following the most likely cause for this condition is: - answers A faulty cooling tower water level controller A centrifugal water pump is known as a lift pump when the: - answers The water supply to the pump suction inlet is below the pump level A TXV is used to maintain constant: - answers Evaporator superheat The chilled water supply to the building is 55F. if the chiller is being used for human comfort, should you be concerned about this , and why? - answers Yes, this temperature is too high for human comfort purpose The packing gland of a centrifugal pump serves to: - answers The drip part of the packing gland gives evidence that there is water in the pump Capacity control of a reciprocating hermetic compressor is typically achieved through - answers Operation of the hot gas bypass valve The most important reason to sub-cool the refrigerant in the condenser is to ensure that: - answers A pure liquid refrigerant will enter the metering device A refrigeration engineer is logging reading from a reciprocating system. compressor discharge temperature have dropped significantly and the suction line pressure is high. which of the following that may be causing this set of condition. - answers An expansion valve that is open to wide A low side float valve is used to maintain: - answers The level of the refrigerant in the evaporator Regarding fire safety, which ASHARE refrigerant safety classification indicates no flammability and lower the toxicity? - answers A1 When an expansion valve is operating properly, at the end of the evaporator will contain: - answers Only superheated vapor What information is not contained in a material safety data sheet-MSDS? - answers Cost of material In a steam turbine, what is the function of the kingsbury thrust bearing - answers Maintain axial positioning of the rotor shaft A centrifugal water pump is considered to be fully primed when - answers The pump is full of liquid Copper tubing refrigerant lines must be installed for a new system. it is a well known service practice that tubing collapses at bends that must be made, the refrigerant engineer should use - answers Lever type tubing bender A reciprocating compressor is making a knocking sound during operation. if the refrigerant worn parts are not causing the knocking, what is probably the cause - answers The slugging of the liquid refrigerant In order for a refrigerant to become superheated in a section of the lowside refrigerant line: - answers Where no liquid refrigerant is present All liquid has been recovered from a system to be overhauled, the system - answers Should not be opened until all vapor has been removed When a refrigerant engineer uses a portable compressor recovery unit to remove vapor refrigerant from a refrigeration system the removal rate of the refrigerant will gradually slow down because - answers The vapor density is decreasing You are the engineer running a 2000-ton (steam-driven turbine) centrifugal refrigeration system, a refrigeration system supplies chilled water to a college campus with multiple buildings. During the course of making your rounds, you check the 9 cell cooling tower on the roof. You note the water level in all of the cooling tower cells is very low. Which one of the following immediate action would take? - answers Add additional make up water to cooling tower A rooftop water cooling tower is connected to a water pump in the building basement with a 12 inches diameter pipe. with the pump turn off, a pressure gauge at the pumps inlet show a pressure of 140 PSIG the height of the water column, in feet, would be closet to. - answers 323 What device protects the steam turbine from excessive speed? - answers governor assembly A refrigeration compressor has failed to turn on. the refrigeration engineer on duty verifies that the electrical circuit to the motor, including all switches and circuit breakers, is complete according to recommended service practice, the next item to be checked would likely be the: - answers Temperature and pressure controls Refrigerants are characterized by their physical properties included flash point, refrigeration effect, and others. of the refrigerant in commercial and industrial the highest latent hear and refrigerant effect is: - answers Ammonia On what characteristics is ASHRAE refrigerant safety group classification system: - answers Flammability and toxicity Of the following, and example of an in-line refrigerant cleaning system that may be used with a centrifugal compressor containing R123 refrigerant is: - answers Refrigerant recycling Information about the physical and chemical properties of a hazardous material can be found in: - answers Material Safety Data Sheet What is the function of the turbine auxiliary oil pump? - answers Establish oil pressure during turbine start up The rupture disc for a low-pressure centrifugal refrigeration machine is normally located on the: - answers Compressor suction What is the primary reason ribbed metal piping is used for electrical wires connected to the refrigeration system shown below? - answers It allows for flexibility and accounts for vibrations A multi-cylinder reciprocating compressor uses cylinder unloaders to regulate capacity, what would not occur if some of the unloaders fail to operate when needed? - answers The chill water temperature will increase As shown in the picture below, the suction gauge of a condenser water pump reads 55 PSI. the pipe supplying the pump is 75 feet long and 12 inches in diameter. approximately how many gallons of water do you expect to obtain if this pipe is drained completely? - answers 440 A water chilling system uses refrigerant R123. a leak in the evaporator shell mat result in - answers A higher than normal high side pressure Capacitors are used on refrigeration motors. of the following, the function of these devices is to? - answers Store electrical charges during starting and running the motor Of the following, centrifugal refrigerant machine is best characterized by: - answers High volume low pressure machine Which of the following ASHRAE refrigerant safety classification is the most flammable? - answers A3 Which of the following correctly describes the object in the picture below? - answers Standpipe hose outlet to put out fires in cae of emergency Modern compressors usually seal the rotating shaft as it exits the compressor housing a spring loaded seal made of - answers Metal or carbon The British Thermal Unit (BTU) is the measurement of heat of energy. if 10 BTU are transferred to 10 pounds of water, the water temperature increase will be closest to: - answers 1F A reciprocating compressor cylinder has a 10 inch bore and 14 inches stroke. the volume of refrigerant, in a cubic inches, will be closer to: - answers 1099