Q 01 FDNY COMPREHENSIVE COURSE REVIEW
◉ To produce the desired evaporator temperature, the power input
is reduced by keeping head pressure...
Answer: Head pressure as low as possible & suction pressure as high
as needed
◉ The accumulator is usually between the...
Answer: Compressor and evaporator
◉ An oiling system in a large centrifugal system should consist of at
least...
Answer: Reservoir, pump and distribution lines
◉ In an evaporator that chills brine, the greatest cooling effect on
the brine results from the...
Answer: Boiling of low pressure liquid
◉ The flow of weak liquor to the absorber is controlled by
A) gas pressure
B) throttling device
C) float valve
,D) pressure of the strong liquor pump
Answer: B) throttling device
◉ The best way of detecting ammonia brine is by using
A) CO2 gas
B) potassium of lime
C) Nessler reagent
D) carbonate of soda
Answer: C) Nessler reagent
◉ The best time to purge an ammonia plant with 250 lbs. of
ammonia is
A) during shut-down, because you will lose ammonia
B) while charging the plant
C) during operation
D) none of the above
Answer: C) during operation
◉ What will make the strong liquor in the absorber decrease?
A) expansion valve open too much
B) A decrease in evaporator load
C) An increase in evaporator load
,D) Too much steam on the generator
Answer: B) A decrease in evaporator load
◉ Which of the following statements is incorrect?
A) A service valve is a key-operated shut-off valve used during
shipment, installation and repairs
B) Brine is a liquid cooled by refrigeration and used for the
transmission of heat
C) A fusible plug has a set-temperature fusible member to relieve
pressure
D) A rupture member automatically ruptures at a predetermined
temperature
Answer: D) A rupture member automatically ruptures at a
predetermined temperature
◉ Oil in a refrigerant should
A) have a high pour point
B) have a low flash point
C) have a high viscosity
D) not contain moisture
Answer: D) not contain moisture
, ◉ In an NH3 dry expansion evaporator with TXV and bulb clamped
properly on the outlet of the evaporator, the superheat is
A) 7 to 10° F
B) 5 to 9° F
C) 20 to 30° F
D) 1 to 2° F
Answer: A) 7 to 10° F
◉ The setting of a fusible plug is
A) 280° F
B) 300° F
C) 380° F
D) 300 psig.
Answer: A) 280° F
◉ If the insulation was removed from the bulb of the expansion
valve, what would happen?
Answer: Flooded evaporator —the TXV bulb opens in a range from
45 to 85° F. If the insulation was removed, the bulb would sense the
temperature in the machine room and keep the TXV open, thus
flooding the evaporator.
◉ To produce the desired evaporator temperature, the power input
is reduced by keeping head pressure...
Answer: Head pressure as low as possible & suction pressure as high
as needed
◉ The accumulator is usually between the...
Answer: Compressor and evaporator
◉ An oiling system in a large centrifugal system should consist of at
least...
Answer: Reservoir, pump and distribution lines
◉ In an evaporator that chills brine, the greatest cooling effect on
the brine results from the...
Answer: Boiling of low pressure liquid
◉ The flow of weak liquor to the absorber is controlled by
A) gas pressure
B) throttling device
C) float valve
,D) pressure of the strong liquor pump
Answer: B) throttling device
◉ The best way of detecting ammonia brine is by using
A) CO2 gas
B) potassium of lime
C) Nessler reagent
D) carbonate of soda
Answer: C) Nessler reagent
◉ The best time to purge an ammonia plant with 250 lbs. of
ammonia is
A) during shut-down, because you will lose ammonia
B) while charging the plant
C) during operation
D) none of the above
Answer: C) during operation
◉ What will make the strong liquor in the absorber decrease?
A) expansion valve open too much
B) A decrease in evaporator load
C) An increase in evaporator load
,D) Too much steam on the generator
Answer: B) A decrease in evaporator load
◉ Which of the following statements is incorrect?
A) A service valve is a key-operated shut-off valve used during
shipment, installation and repairs
B) Brine is a liquid cooled by refrigeration and used for the
transmission of heat
C) A fusible plug has a set-temperature fusible member to relieve
pressure
D) A rupture member automatically ruptures at a predetermined
temperature
Answer: D) A rupture member automatically ruptures at a
predetermined temperature
◉ Oil in a refrigerant should
A) have a high pour point
B) have a low flash point
C) have a high viscosity
D) not contain moisture
Answer: D) not contain moisture
, ◉ In an NH3 dry expansion evaporator with TXV and bulb clamped
properly on the outlet of the evaporator, the superheat is
A) 7 to 10° F
B) 5 to 9° F
C) 20 to 30° F
D) 1 to 2° F
Answer: A) 7 to 10° F
◉ The setting of a fusible plug is
A) 280° F
B) 300° F
C) 380° F
D) 300 psig.
Answer: A) 280° F
◉ If the insulation was removed from the bulb of the expansion
valve, what would happen?
Answer: Flooded evaporator —the TXV bulb opens in a range from
45 to 85° F. If the insulation was removed, the bulb would sense the
temperature in the machine room and keep the TXV open, thus
flooding the evaporator.
