NYC HIGH PRESSURE BOILER OPERATING ENGINEER LICENSE EXAM NEWEST
EVALUATED EXAM PRACTICE 100 QUESTIONS 2026-2027|ORIGINAL
QUESTIONS & ANSWERS |DETAILED RATIONALES |HINTED COMPLETE EXAM
PREP GRADED A+*INSTANT DOWNLOAD PDF*
1. A high-pressure boiler operator notices that the boiler water level is
rapidly falling while the burner is firing. What should be done FIRST?
A. Increase the firing rate
B. Open the bottom blowdown valve
C. Shut off the burner and investigate the cause of the low-water condition
D. Open the main steam valve wider
Answer: C. Shut off the burner and investigate the cause of the low-water
condition
Low water can expose heating surfaces to excessive temperatures and may
result in catastrophic boiler failure. The heat input must be stopped
immediately.
2. What is the primary purpose of a boiler safety valve?
A. To regulate combustion air
B. To maintain the normal water level
C. To prevent excessive steam pressure
D. To control feedwater temperature
Answer: C. To prevent excessive steam pressure
The safety valve automatically releases steam when pressure reaches its set
pressure, protecting the boiler from overpressure.
3. Which instrument provides the operator with a direct indication of the
boiler's steam pressure?
A. Thermocouple
B. Pressure gauge
C. Water column
D. Draft gauge
Answer: B. Pressure gauge
,The steam pressure gauge indicates the pressure inside the boiler or steam
space.
4. The purpose of a low-water fuel cutoff is to:
A. Increase boiler efficiency
B. Prevent excessive steam temperature
C. Stop the burner when the water level becomes dangerously low
D. Increase feedwater pressure
Answer: C. Stop the burner when the water level becomes dangerously low
The low-water fuel cutoff protects the boiler against firing with insufficient
water covering the heating surfaces.
5. Before opening a boiler's main steam stop valve after bringing the boiler
up to pressure, the operator should primarily ensure that:
A. The boiler is completely drained
B. The steam line is properly warmed and drained of condensate
C. The burner is operating at maximum capacity
D. The safety valve is manually opened
Answer: B. The steam line is properly warmed and drained of condensate
Warming the steam line and removing condensate reduces the possibility of
water hammer.
6. Water hammer in a steam system is most commonly caused by:
A. Excessive oxygen in feedwater
B. Condensate accumulating in steam piping
C. High boiler efficiency
D. Low combustion temperature
Answer: B. Condensate accumulating in steam piping
When steam rapidly moves condensate or condenses against trapped water,
severe pressure shocks can occur.
7. What is the primary function of a boiler feedwater pump?
,A. Remove dissolved gases
B. Supply water to the boiler at sufficient pressure
C. Reduce steam pressure
D. Control the burner flame
Answer: B. Supply water to the boiler at sufficient pressure
The feedwater pump must develop enough pressure to overcome boiler
pressure and the resistance of the feedwater system.
8. Why is boiler water treatment important?
A. It increases the color of the flame
B. It prevents scale, corrosion, and other water-related problems
C. It eliminates the need for inspections
D. It increases steam pressure automatically
Answer: B. It prevents scale, corrosion, and other water-related problems
Proper water treatment helps control scale formation, corrosion, dissolved
gases, and other conditions that can damage boiler components.
9. Scale on boiler heating surfaces generally causes:
A. Improved heat transfer
B. Reduced fuel consumption
C. Increased metal temperature and reduced heat-transfer efficiency
D. Lower combustion temperature
Answer: C. Increased metal temperature and reduced heat-transfer efficiency
Scale acts as an insulating layer. More heat remains in the metal, increasing
tube or shell temperature and reducing efficiency.
10.What is the primary purpose of boiler blowdown?
A. Increase dissolved solids
B. Remove concentrated impurities from boiler water
C. Increase steam pressure
D. Increase burner capacity
Answer: B. Remove concentrated impurities from boiler water
, Blowdown removes water containing concentrated dissolved and suspended
solids, helping maintain acceptable boiler-water conditions.
11.Which condition is most likely to cause foaming and carryover?
A. Excessively pure boiler water
B. High concentration of dissolved or suspended solids
C. Low steam demand
D. Low feedwater temperature
Answer: B. High concentration of dissolved or suspended solids
High concentrations of contaminants can destabilize the water surface and
cause water droplets to be carried into the steam system.
12.What is priming in a boiler?
A. Ignition of the pilot burner
B. Carryover of boiler water with the steam
C. Removal of sludge
D. Cooling of feedwater
Answer: B. Carryover of boiler water with the steam
Priming occurs when water is mechanically carried from the boiler into the
steam outlet.
13.The main purpose of a steam separator is to:
A. Increase combustion temperature
B. Remove moisture from steam
C. Add chemicals to feedwater
D. Increase boiler pressure
Answer: B. Remove moisture from steam
A separator removes entrained water droplets from steam, improving steam
quality and reducing moisture-related problems.
14.What is the purpose of a deaerator?
A. Remove oxygen and other dissolved gases from feedwater
B. Increase boiler pressure
EVALUATED EXAM PRACTICE 100 QUESTIONS 2026-2027|ORIGINAL
QUESTIONS & ANSWERS |DETAILED RATIONALES |HINTED COMPLETE EXAM
PREP GRADED A+*INSTANT DOWNLOAD PDF*
1. A high-pressure boiler operator notices that the boiler water level is
rapidly falling while the burner is firing. What should be done FIRST?
A. Increase the firing rate
B. Open the bottom blowdown valve
C. Shut off the burner and investigate the cause of the low-water condition
D. Open the main steam valve wider
Answer: C. Shut off the burner and investigate the cause of the low-water
condition
Low water can expose heating surfaces to excessive temperatures and may
result in catastrophic boiler failure. The heat input must be stopped
immediately.
2. What is the primary purpose of a boiler safety valve?
A. To regulate combustion air
B. To maintain the normal water level
C. To prevent excessive steam pressure
D. To control feedwater temperature
Answer: C. To prevent excessive steam pressure
The safety valve automatically releases steam when pressure reaches its set
pressure, protecting the boiler from overpressure.
3. Which instrument provides the operator with a direct indication of the
boiler's steam pressure?
A. Thermocouple
B. Pressure gauge
C. Water column
D. Draft gauge
Answer: B. Pressure gauge
,The steam pressure gauge indicates the pressure inside the boiler or steam
space.
4. The purpose of a low-water fuel cutoff is to:
A. Increase boiler efficiency
B. Prevent excessive steam temperature
C. Stop the burner when the water level becomes dangerously low
D. Increase feedwater pressure
Answer: C. Stop the burner when the water level becomes dangerously low
The low-water fuel cutoff protects the boiler against firing with insufficient
water covering the heating surfaces.
5. Before opening a boiler's main steam stop valve after bringing the boiler
up to pressure, the operator should primarily ensure that:
A. The boiler is completely drained
B. The steam line is properly warmed and drained of condensate
C. The burner is operating at maximum capacity
D. The safety valve is manually opened
Answer: B. The steam line is properly warmed and drained of condensate
Warming the steam line and removing condensate reduces the possibility of
water hammer.
6. Water hammer in a steam system is most commonly caused by:
A. Excessive oxygen in feedwater
B. Condensate accumulating in steam piping
C. High boiler efficiency
D. Low combustion temperature
Answer: B. Condensate accumulating in steam piping
When steam rapidly moves condensate or condenses against trapped water,
severe pressure shocks can occur.
7. What is the primary function of a boiler feedwater pump?
,A. Remove dissolved gases
B. Supply water to the boiler at sufficient pressure
C. Reduce steam pressure
D. Control the burner flame
Answer: B. Supply water to the boiler at sufficient pressure
The feedwater pump must develop enough pressure to overcome boiler
pressure and the resistance of the feedwater system.
8. Why is boiler water treatment important?
A. It increases the color of the flame
B. It prevents scale, corrosion, and other water-related problems
C. It eliminates the need for inspections
D. It increases steam pressure automatically
Answer: B. It prevents scale, corrosion, and other water-related problems
Proper water treatment helps control scale formation, corrosion, dissolved
gases, and other conditions that can damage boiler components.
9. Scale on boiler heating surfaces generally causes:
A. Improved heat transfer
B. Reduced fuel consumption
C. Increased metal temperature and reduced heat-transfer efficiency
D. Lower combustion temperature
Answer: C. Increased metal temperature and reduced heat-transfer efficiency
Scale acts as an insulating layer. More heat remains in the metal, increasing
tube or shell temperature and reducing efficiency.
10.What is the primary purpose of boiler blowdown?
A. Increase dissolved solids
B. Remove concentrated impurities from boiler water
C. Increase steam pressure
D. Increase burner capacity
Answer: B. Remove concentrated impurities from boiler water
, Blowdown removes water containing concentrated dissolved and suspended
solids, helping maintain acceptable boiler-water conditions.
11.Which condition is most likely to cause foaming and carryover?
A. Excessively pure boiler water
B. High concentration of dissolved or suspended solids
C. Low steam demand
D. Low feedwater temperature
Answer: B. High concentration of dissolved or suspended solids
High concentrations of contaminants can destabilize the water surface and
cause water droplets to be carried into the steam system.
12.What is priming in a boiler?
A. Ignition of the pilot burner
B. Carryover of boiler water with the steam
C. Removal of sludge
D. Cooling of feedwater
Answer: B. Carryover of boiler water with the steam
Priming occurs when water is mechanically carried from the boiler into the
steam outlet.
13.The main purpose of a steam separator is to:
A. Increase combustion temperature
B. Remove moisture from steam
C. Add chemicals to feedwater
D. Increase boiler pressure
Answer: B. Remove moisture from steam
A separator removes entrained water droplets from steam, improving steam
quality and reducing moisture-related problems.
14.What is the purpose of a deaerator?
A. Remove oxygen and other dissolved gases from feedwater
B. Increase boiler pressure
