NJ BLUE SEAL BOILER | REAL EXAM QUESTIONS AND 100%
VERIFIED ANSWERS | LATEST VERSION 2026/2027 (PASS
GUARANTEE) GRADED A+
1. What type of boiler has water and steam inside the tubes, with
combustion gases passing around the outside of the tubes?
A. Fire-tube boiler
B. Water-tube boiler
C. Cast iron boiler
D. Electric boiler
ANSWER : B
2. What type of boiler has combustion gases passing through the inside of
tubes that are surrounded by water?
A. Water-tube boiler
B. Fire-tube boiler
C. Once-through boiler
D. Supercritical boiler
ANSWER : B
3. Which boiler design is generally favored for high-pressure, high-capacity
steam generation?
A. Fire-tube boiler
B. Cast iron sectional boiler
C. Water-tube boiler
D. Vertical tubeless boiler
ANSWER : C
4. What is the primary purpose of the steam drum in a water-tube boiler?
A. Burn fuel efficiently
, B. Separate steam from water
C. Preheat combustion air
D. Store fuel oil
ANSWER : B
5. What is the enclosed space where fuel is burned in a boiler called?
A. Furnace
B. Economizer
C. Plenum
D. Mud drum
ANSWER : A
6. In a Scotch marine boiler, what is the large central cylindrical chamber
called?
A. Mud drum
B. Steam drum
C. Furnace (firebox) tube
D. Downcomer
ANSWER : C
7. What is the function of stay bolts in a firebox-type boiler?
A. Increase draft
B. Support flat surfaces against internal pressure
C. Reduce scale buildup
D. Cool the burner
ANSWER : B
8. What is the purpose of a superheater?
A. Cool the flue gas
B. Raise steam temperature above saturation temperature
C. Remove dissolved oxygen
D. Soften makeup water
ANSWER : B
9. What is the main function of an economizer in a boiler system?
A. Increase steam pressure
B. Preheat feedwater using waste heat from flue gas
, C. Remove suspended solids
D. Generate electricity
ANSWER : B
10. "Boiler heating surface" refers to which of the following?
A. The painted exterior of the boiler
B. Surface area exposed to hot gases on one side and water/steam on the
other
C. The insulation thickness
D. The area of the burner nozzle
ANSWER : B
11. Boilers may be classified as internally fired or externally fired based on
what?
A. Fuel type used
B. Location of the furnace relative to the shell
C. Steam pressure rating
D. Number of passes
ANSWER : B
12. What does the term "package boiler" describe?
A. A boiler sold without a burner
B. A boiler shipped already mounted and wired as a complete factory-
assembled unit
C. A boiler used only for heating buildings
D. A boiler with no safety valve
ANSWER : B
13. What is the purpose of the mud drum in a water-tube boiler?
A. Generate additional steam
B. Collect sediment and sludge at the lowest point
C. House the burner assembly
D. Hold the main safety valve
ANSWER : B
14. Under typical boiler code definitions, what generally distinguishes a
"high-pressure" steam boiler?
, A. Operating above 15 psig
B. Operating below 15 psig
C. Using only gas fuel
D. Having no safety valve
ANSWER : A
15. What best describes a composite (combination) boiler?
A. A boiler that uses only solid fuel
B. A boiler that incorporates features of both fire-tube and water-tube
design
C. A boiler with no drum
D. A boiler that cannot generate steam
ANSWER : B
16. Why are boiler shells and drums typically constructed of low-carbon
steel?
A. It is the cheapest material available
B. It offers ductility, weldability, and resistance to brittle fracture
C. It rusts faster, which is desirable
D. It conducts electricity better
ANSWER : B
17. What is the function of baffles inside a boiler?
A. Reduce water hardness
B. Direct the flow of combustion gases to maximize heat transfer
C. Filter the fuel supply
D. Support the safety valve
ANSWER : B
18. What are waterwall tubes in a boiler furnace used for?
A. Supplying combustion air
B. Lining the furnace to absorb radiant heat directly into the water
C. Storing condensate
D. Filtering flue gas particulates
ANSWER : B
19. What is the function of downcomer tubes in a natural-circulation boiler?
VERIFIED ANSWERS | LATEST VERSION 2026/2027 (PASS
GUARANTEE) GRADED A+
1. What type of boiler has water and steam inside the tubes, with
combustion gases passing around the outside of the tubes?
A. Fire-tube boiler
B. Water-tube boiler
C. Cast iron boiler
D. Electric boiler
ANSWER : B
2. What type of boiler has combustion gases passing through the inside of
tubes that are surrounded by water?
A. Water-tube boiler
B. Fire-tube boiler
C. Once-through boiler
D. Supercritical boiler
ANSWER : B
3. Which boiler design is generally favored for high-pressure, high-capacity
steam generation?
A. Fire-tube boiler
B. Cast iron sectional boiler
C. Water-tube boiler
D. Vertical tubeless boiler
ANSWER : C
4. What is the primary purpose of the steam drum in a water-tube boiler?
A. Burn fuel efficiently
, B. Separate steam from water
C. Preheat combustion air
D. Store fuel oil
ANSWER : B
5. What is the enclosed space where fuel is burned in a boiler called?
A. Furnace
B. Economizer
C. Plenum
D. Mud drum
ANSWER : A
6. In a Scotch marine boiler, what is the large central cylindrical chamber
called?
A. Mud drum
B. Steam drum
C. Furnace (firebox) tube
D. Downcomer
ANSWER : C
7. What is the function of stay bolts in a firebox-type boiler?
A. Increase draft
B. Support flat surfaces against internal pressure
C. Reduce scale buildup
D. Cool the burner
ANSWER : B
8. What is the purpose of a superheater?
A. Cool the flue gas
B. Raise steam temperature above saturation temperature
C. Remove dissolved oxygen
D. Soften makeup water
ANSWER : B
9. What is the main function of an economizer in a boiler system?
A. Increase steam pressure
B. Preheat feedwater using waste heat from flue gas
, C. Remove suspended solids
D. Generate electricity
ANSWER : B
10. "Boiler heating surface" refers to which of the following?
A. The painted exterior of the boiler
B. Surface area exposed to hot gases on one side and water/steam on the
other
C. The insulation thickness
D. The area of the burner nozzle
ANSWER : B
11. Boilers may be classified as internally fired or externally fired based on
what?
A. Fuel type used
B. Location of the furnace relative to the shell
C. Steam pressure rating
D. Number of passes
ANSWER : B
12. What does the term "package boiler" describe?
A. A boiler sold without a burner
B. A boiler shipped already mounted and wired as a complete factory-
assembled unit
C. A boiler used only for heating buildings
D. A boiler with no safety valve
ANSWER : B
13. What is the purpose of the mud drum in a water-tube boiler?
A. Generate additional steam
B. Collect sediment and sludge at the lowest point
C. House the burner assembly
D. Hold the main safety valve
ANSWER : B
14. Under typical boiler code definitions, what generally distinguishes a
"high-pressure" steam boiler?
, A. Operating above 15 psig
B. Operating below 15 psig
C. Using only gas fuel
D. Having no safety valve
ANSWER : A
15. What best describes a composite (combination) boiler?
A. A boiler that uses only solid fuel
B. A boiler that incorporates features of both fire-tube and water-tube
design
C. A boiler with no drum
D. A boiler that cannot generate steam
ANSWER : B
16. Why are boiler shells and drums typically constructed of low-carbon
steel?
A. It is the cheapest material available
B. It offers ductility, weldability, and resistance to brittle fracture
C. It rusts faster, which is desirable
D. It conducts electricity better
ANSWER : B
17. What is the function of baffles inside a boiler?
A. Reduce water hardness
B. Direct the flow of combustion gases to maximize heat transfer
C. Filter the fuel supply
D. Support the safety valve
ANSWER : B
18. What are waterwall tubes in a boiler furnace used for?
A. Supplying combustion air
B. Lining the furnace to absorb radiant heat directly into the water
C. Storing condensate
D. Filtering flue gas particulates
ANSWER : B
19. What is the function of downcomer tubes in a natural-circulation boiler?
