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Q-01 FDNY Questions and Correct
Answers/ Latest Update / Already Graded
Rupture members, when used in parallel with a relief valve, are not to
exceed _____% above designed working pressure
Ans: 20%
Butterfly valve: where can it be used?
Ans: Can be used on the inlet and outlet of a water pump
What electrical motor protection device automatically resets itself?
Ans: The thermal protector
746 watts equals how many kilowatt hours?
Ans: .746 kilowatt hours
What position is the liquid line service valve normally in?
Ans: Back-seated
In an operating evaporator, oil stays on top of which refrigerant?
All rights reserved © 2025/ 2026 |
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Ans: Carbon dioxide, R-744
At what pressure does the relief valve blow on a high pressure
machine?
Ans: 300 psi
What would indicate a restriction (such as dirt or scale) in the liquid
line?
Ans: Frost immediately after the restriction
What does solubility mean?
Ans: The ability of a refrigerant to mix with other substances
Charging Vapor —In a compression system, where do you charge the
vapor?
Ans: Suction side of the compressor at the Suction Service
Valve
When comparing a brine with s PH of 8 to one with a PH of 10, its
alkalinity is:
Ans: 100 times greater (ex. PH 8 to PH 9 is 10 times greater)
All rights reserved © 2025/ 2026 |
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In an efficiently operating induced draft cooling tower, the leaving
water is between:
Ans: Dry bulb and wet bulb temperature
To produce the desired evaporator temperature, the power input is
reduced by keeping head pressure...
Ans: Head pressure as low as possible & suction pressure as
high as needed
The accumulator is usually between the...
Ans: Compressor and evaporator
An oiling system in a large centrifugal system should consist of at
least...
Ans: Reservoir, pump and distribution lines
In an evaporator that chills brine, the greatest cooling effect on the
brine results from the...
Ans: Boiling of low pressure liquid
All rights reserved © 2025/ 2026 |
, Page |4
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
Ans: 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
Ans: 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
All rights reserved © 2025/ 2026 |
Q-01 FDNY Questions and Correct
Answers/ Latest Update / Already Graded
Rupture members, when used in parallel with a relief valve, are not to
exceed _____% above designed working pressure
Ans: 20%
Butterfly valve: where can it be used?
Ans: Can be used on the inlet and outlet of a water pump
What electrical motor protection device automatically resets itself?
Ans: The thermal protector
746 watts equals how many kilowatt hours?
Ans: .746 kilowatt hours
What position is the liquid line service valve normally in?
Ans: Back-seated
In an operating evaporator, oil stays on top of which refrigerant?
All rights reserved © 2025/ 2026 |
, Page |2
Ans: Carbon dioxide, R-744
At what pressure does the relief valve blow on a high pressure
machine?
Ans: 300 psi
What would indicate a restriction (such as dirt or scale) in the liquid
line?
Ans: Frost immediately after the restriction
What does solubility mean?
Ans: The ability of a refrigerant to mix with other substances
Charging Vapor —In a compression system, where do you charge the
vapor?
Ans: Suction side of the compressor at the Suction Service
Valve
When comparing a brine with s PH of 8 to one with a PH of 10, its
alkalinity is:
Ans: 100 times greater (ex. PH 8 to PH 9 is 10 times greater)
All rights reserved © 2025/ 2026 |
, Page |3
In an efficiently operating induced draft cooling tower, the leaving
water is between:
Ans: Dry bulb and wet bulb temperature
To produce the desired evaporator temperature, the power input is
reduced by keeping head pressure...
Ans: Head pressure as low as possible & suction pressure as
high as needed
The accumulator is usually between the...
Ans: Compressor and evaporator
An oiling system in a large centrifugal system should consist of at
least...
Ans: Reservoir, pump and distribution lines
In an evaporator that chills brine, the greatest cooling effect on the
brine results from the...
Ans: Boiling of low pressure liquid
All rights reserved © 2025/ 2026 |
, Page |4
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
Ans: 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
Ans: 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
All rights reserved © 2025/ 2026 |
