FDNY Q01/Q99 Written EXAM Questions with
100% Correct Answers | Verified | Updated (Actual
Exam) 2026\2027
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.
pg. 1
,2|Page
On the most common three-phase, four-wire service, the voltage
between any phase and neutral should be
A) 105 volts
B) 120 volts
C) 208 volts
D) 220 volts ......ANSWER......B) 120 volts
A refrigerant overcharge would
A) increase head pressure
B) decrease head pressure
C) decrease solution-side pressure
D) decrease discharge-side pressure ......ANSWER......A) increase head
pressure
A dryer is generally installed with other equipment in a commercial
Freon compressor system. The recommended location of this dryer is
on the
A) high-pressure line between condenser and reciever
B) suction line between evaporator and compressor
C) discharge line between compressor and condenser
D) liquid line between receiver and expansion valve ......ANSWER......D)
liquid line between receiver and expansion valve
pg. 2
,3|Page
R-22 —What does it smell like? ......ANSWER......Odorless
Desirable characteristics of a refrigerant:
A) High __________
B) Low __________ ......ANSWER......A) High critical point
B) Low freezing point
Centrifugal Feed Water Pump
A) Start-up procedure
B) Shut-down procedure ......ANSWER......A) Start-up procedure
1) Lock-out, tag-out
2) Close discharge valve
3) Open suction valve
4) Turn on
5) Open discharge valve
B) Shut-down procedure
1) Lock-out, tag-out
2) close suction valve
3) close discharge valve
In order to vary the capacity of an absorption plant, you should regulate
the.. ......ANSWER......Flow of the water to the condenser
pg. 3
, 4|Page
600,000 btu per hour equals how many tons of refrigeration?
A) 300
B) 3,000
C) 500
D) 50 ......ANSWER......D) 50
Heat transfer takes place by
A) evaporation, conduction and condensation
B) radiation, conduction and convection
C) condensation, evaporation and radiation
D) sublimation, evaporation and convection ......ANSWER......B)
radiation, conduction and convection
Refrigerant recovery is defined as
A) Removing the refrigerant from a system and storing it in an external
container, with the lowest emissions possible.
B) Reprocessing a refrigerant into a new product that can be reused in
another system.
C) The process of cleaning a refrigerant of dirt and contaminates, such
as oil, acid, foreign material and non condensibles.
D) None of the above. ......ANSWER......A) Removing the refrigerant
from a system and storing it in an external container, with the lowest
emissions possible.
pg. 4