Q-01 FDNY LATEST UPDATED 2025/2026
Questions And Revised Correct Answers
100% PASSED!! GRADED AT A+
1. Rupture members, when used in parallel with a relief valve, are not
to exceed _____% above designed working pressure - ANSWER
20%
2. Butterfly valve: where can it be used? - ANSWER Can be used on
the inlet and outlet of a water pump
3. On which tachometer do you mark the rotating object with
reflecting tape?
A) The electronic tachometer (stroboscope)
B) The digital photo tachometer
C) The centrifugal-type tachometer
D) The chronometric tachometer - ANSWER B) The digital
photo tachometer
4. One characteristic of a synchronous motor is that it operates at
A) high starting torque
B) constant speed
C) causes lagging power factor
D) all of the above - ANSWER B) constant speed
5. If during does not occur in a refrigerating system, what is the
result?
A) High-head pressure
B) Low-condenser pressure
C) Low-head pressure
D) None of the above - ANSWER A) High-head pressure
,6. A wound-rotor induction motor with external resistance is a
A) multispeed motor
B) constant-speed motor
C) single-speed motor
D) waterproof cover - ANSWER A) multispeed motor
7. In a Freon refrigerating system in which all piping is made up of
hard copper fittings and streamlined "wrought"-type fittings, the
joints should be
A) screwed
B) soldered or brazed
C) flanged with ground faces
D) flanged with lined rubber gaskets - ANSWER B) soldered or
brazed
8. What electrical motor protection device automatically resets itself?
- ANSWER The thermal protector
9. 746 watts equals how many kilowatt hours? - ANSWER .746
kilowatt hours
10. What position is the liquid line service valve normally in? -
ANSWER Back-seated
11. In an operating evaporator, oil stays on top of which
refrigerant? - ANSWER Carbon dioxide, R-744
12. At what pressure does the relief valve blow on a high
pressure machine? - ANSWER 300 psi
13. What would indicate a restriction (such as dirt or scale) in the
liquid line? - ANSWER Frost immediately after the restriction
,14. What does solubility mean? - ANSWER The ability of a
refrigerant to mix with other substances
15. Charging Vapor —In a compression system, where do you
charge the vapor? - ANSWER Suction side of the compressor at
the Suction Service Valve
16. When comparing a brine with s PH of 8 to one with a PH of
10, its alkalinity is: - ANSWER 100 times greater (ex. PH 8 to PH
9 is 10 times greater)
17. In an efficiently operating induced draft cooling tower, the
leaving water is between: - ANSWER Dry bulb and wet bulb
temperature
18. 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
19. The accumulator is usually between the... - ANSWER
Compressor and evaporator
20. An oiling system in a large centrifugal system should consist
of at least... - ANSWER Reservoir, pump and distribution lines
21. In an evaporator that chills brine, the greatest cooling effect
on the brine results from the... - ANSWER Boiling of low pressure
liquid
22. 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
, 23. 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
24. 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
25. 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
26. 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
27. Oil in a refrigerant should
A) have a high pour point
B) have a low flash point
Questions And Revised Correct Answers
100% PASSED!! GRADED AT A+
1. Rupture members, when used in parallel with a relief valve, are not
to exceed _____% above designed working pressure - ANSWER
20%
2. Butterfly valve: where can it be used? - ANSWER Can be used on
the inlet and outlet of a water pump
3. On which tachometer do you mark the rotating object with
reflecting tape?
A) The electronic tachometer (stroboscope)
B) The digital photo tachometer
C) The centrifugal-type tachometer
D) The chronometric tachometer - ANSWER B) The digital
photo tachometer
4. One characteristic of a synchronous motor is that it operates at
A) high starting torque
B) constant speed
C) causes lagging power factor
D) all of the above - ANSWER B) constant speed
5. If during does not occur in a refrigerating system, what is the
result?
A) High-head pressure
B) Low-condenser pressure
C) Low-head pressure
D) None of the above - ANSWER A) High-head pressure
,6. A wound-rotor induction motor with external resistance is a
A) multispeed motor
B) constant-speed motor
C) single-speed motor
D) waterproof cover - ANSWER A) multispeed motor
7. In a Freon refrigerating system in which all piping is made up of
hard copper fittings and streamlined "wrought"-type fittings, the
joints should be
A) screwed
B) soldered or brazed
C) flanged with ground faces
D) flanged with lined rubber gaskets - ANSWER B) soldered or
brazed
8. What electrical motor protection device automatically resets itself?
- ANSWER The thermal protector
9. 746 watts equals how many kilowatt hours? - ANSWER .746
kilowatt hours
10. What position is the liquid line service valve normally in? -
ANSWER Back-seated
11. In an operating evaporator, oil stays on top of which
refrigerant? - ANSWER Carbon dioxide, R-744
12. At what pressure does the relief valve blow on a high
pressure machine? - ANSWER 300 psi
13. What would indicate a restriction (such as dirt or scale) in the
liquid line? - ANSWER Frost immediately after the restriction
,14. What does solubility mean? - ANSWER The ability of a
refrigerant to mix with other substances
15. Charging Vapor —In a compression system, where do you
charge the vapor? - ANSWER Suction side of the compressor at
the Suction Service Valve
16. When comparing a brine with s PH of 8 to one with a PH of
10, its alkalinity is: - ANSWER 100 times greater (ex. PH 8 to PH
9 is 10 times greater)
17. In an efficiently operating induced draft cooling tower, the
leaving water is between: - ANSWER Dry bulb and wet bulb
temperature
18. 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
19. The accumulator is usually between the... - ANSWER
Compressor and evaporator
20. An oiling system in a large centrifugal system should consist
of at least... - ANSWER Reservoir, pump and distribution lines
21. In an evaporator that chills brine, the greatest cooling effect
on the brine results from the... - ANSWER Boiling of low pressure
liquid
22. 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
, 23. 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
24. 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
25. 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
26. 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
27. Oil in a refrigerant should
A) have a high pour point
B) have a low flash point
