NYC Stationary Engineer License Exam
With Actual Questions & Verified Answers,
Plus Explained Rationales/Expert Verified
For Guaranteed 100% Pass 2026/Latest
Update/Instant Download Pdf
1. A stationary engineer is primarily responsible for operating which
system?
A. Electrical distribution only
B. Boiler and HVAC plant systems
C. Plumbing fixtures in residential units
D. Elevator installation systems
Rationale: A stationary engineer operates and maintains large
mechanical systems such as boilers, chillers, HVAC, and related
plant equipment that support building operations.
2. What is the main purpose of a boiler in a facility?
A. To cool air for ventilation
B. To generate steam or hot water for heating
C. To filter drinking water
D. To compress refrigerant gas
Rationale: A boiler’s primary function is to produce steam or hot
water used for heating, sterilization, or mechanical processes in
a building.
3. Which fuel is most commonly used in modern high-efficiency
boilers?
A. Coal
B. Wood
, C. Natural gas
D. Diesel only
Rationale: Natural gas is widely used due to its efficiency, lower
emissions, and ease of control compared to solid or heavy fuels.
4. What does a pressure relief valve do in a boiler system?
A. Increases steam pressure
B. Controls fuel flow
C. Releases excess pressure to prevent explosion
D. Measures water hardness
Rationale: A pressure relief valve automatically opens to release
excess pressure, protecting the boiler from dangerous
overpressure conditions.
5. What is the function of a condensate return system?
A. Removes combustion gases
B. Returns condensed steam back to the boiler
C. Filters fuel before combustion
D. Increases electrical efficiency
Rationale: Condensate return systems recycle water formed from
steam back into the boiler, improving efficiency and reducing
water waste.
6. Which instrument measures boiler pressure?
A. Thermometer
B. Flow meter
C. Pressure gauge
D. Psychrometer
Rationale: A pressure gauge is used to monitor the internal
pressure of a boiler system to ensure safe operation.
7. What is the purpose of a combustion analyzer?
A. Measures water flow
, B. Evaluates combustion efficiency and emissions
C. Controls electrical load
D. Tests pipe thickness
Rationale: A combustion analyzer measures gases like CO2 and
O2 to ensure efficient and safe fuel burning.
8. What is the danger of low water level in a boiler?
A. Increased efficiency
B. Reduced fuel use
C. Overheating and possible boiler damage
D. Lower steam pressure stability
Rationale: Low water levels expose boiler surfaces to extreme
heat, risking overheating and equipment failure.
9. What component regulates fuel supply to the burner?
A. Steam trap
B. Heat exchanger
C. Fuel valve
D. Expansion tank
Rationale: The fuel valve controls the amount of fuel delivered to
the burner for proper combustion.
10. What is a steam trap used for?
A. Increases steam temperature
B. Generates steam
C. Removes condensate without losing steam
D. Measures pressure
Rationale: Steam traps discharge condensate and air while
retaining usable steam in the system.
11. Which safety device prevents backflow in piping systems?
A. Pressure gauge
B. Thermostat
With Actual Questions & Verified Answers,
Plus Explained Rationales/Expert Verified
For Guaranteed 100% Pass 2026/Latest
Update/Instant Download Pdf
1. A stationary engineer is primarily responsible for operating which
system?
A. Electrical distribution only
B. Boiler and HVAC plant systems
C. Plumbing fixtures in residential units
D. Elevator installation systems
Rationale: A stationary engineer operates and maintains large
mechanical systems such as boilers, chillers, HVAC, and related
plant equipment that support building operations.
2. What is the main purpose of a boiler in a facility?
A. To cool air for ventilation
B. To generate steam or hot water for heating
C. To filter drinking water
D. To compress refrigerant gas
Rationale: A boiler’s primary function is to produce steam or hot
water used for heating, sterilization, or mechanical processes in
a building.
3. Which fuel is most commonly used in modern high-efficiency
boilers?
A. Coal
B. Wood
, C. Natural gas
D. Diesel only
Rationale: Natural gas is widely used due to its efficiency, lower
emissions, and ease of control compared to solid or heavy fuels.
4. What does a pressure relief valve do in a boiler system?
A. Increases steam pressure
B. Controls fuel flow
C. Releases excess pressure to prevent explosion
D. Measures water hardness
Rationale: A pressure relief valve automatically opens to release
excess pressure, protecting the boiler from dangerous
overpressure conditions.
5. What is the function of a condensate return system?
A. Removes combustion gases
B. Returns condensed steam back to the boiler
C. Filters fuel before combustion
D. Increases electrical efficiency
Rationale: Condensate return systems recycle water formed from
steam back into the boiler, improving efficiency and reducing
water waste.
6. Which instrument measures boiler pressure?
A. Thermometer
B. Flow meter
C. Pressure gauge
D. Psychrometer
Rationale: A pressure gauge is used to monitor the internal
pressure of a boiler system to ensure safe operation.
7. What is the purpose of a combustion analyzer?
A. Measures water flow
, B. Evaluates combustion efficiency and emissions
C. Controls electrical load
D. Tests pipe thickness
Rationale: A combustion analyzer measures gases like CO2 and
O2 to ensure efficient and safe fuel burning.
8. What is the danger of low water level in a boiler?
A. Increased efficiency
B. Reduced fuel use
C. Overheating and possible boiler damage
D. Lower steam pressure stability
Rationale: Low water levels expose boiler surfaces to extreme
heat, risking overheating and equipment failure.
9. What component regulates fuel supply to the burner?
A. Steam trap
B. Heat exchanger
C. Fuel valve
D. Expansion tank
Rationale: The fuel valve controls the amount of fuel delivered to
the burner for proper combustion.
10. What is a steam trap used for?
A. Increases steam temperature
B. Generates steam
C. Removes condensate without losing steam
D. Measures pressure
Rationale: Steam traps discharge condensate and air while
retaining usable steam in the system.
11. Which safety device prevents backflow in piping systems?
A. Pressure gauge
B. Thermostat
