High Pressure Boiler Black Seal Exam
HIGH PRESSURE BOILER BLACK SEAL EXAM NEWEST
2025/2026 COMPLETE ALL QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW VERSION!
What must take place in order for combustion air to flow open automatically
during equipment operation? - ANSWER-There must be an adequate opening for
the flow of fuel gas into the confines of the boiler room to ensure proper
combustion
Furnace explosions can best be avoided by: - ANSWER-purging the furnace after
any flame interruption
What type of draft system is used to overcome resistance on power boilers
equipped with an economizer? - ANSWER-an induced draft system
What is the Btu content of natural gas? - ANSWER-100,000 Btu/therm
The term viscosity can best be defined as: - ANSWER-the point at which oil starts
to flow
A gradual increase in the stack temperature could indicate what condition in a
boiler? - ANSWER-heating surface fouling
1|Page
, High Pressure Boiler Black Seal Exam
In the ignition system on an oil burner, what causes the spark to jump the gap and
ignite the fuel? - ANSWER-a high voltage spark of 10,000V DC produced from the
transformer, jumps the gap between the electrode tips.
What are the three types of draft used in power plants? - ANSWER-natural, forced,
and induced
What would a stack gas reading of fair to good combustion look like? - ANSWER-
low oxygen and carbon monoxide, high carbon dioxide
When a discharge valve is opened to the atmosphere, the pressure on the
upstream side of the valve will: - ANSWER-decrease, and the pressure on the
downstream side will remain the same.
By N.J.A.C. 12:90 rules, what is the minimum thickness allowed for atmospheric
type blowdown tank? - ANSWER-5/16 inch
What would one standard atmosphere at 14.7 psi be equivalent to in feet of
water? - ANSWER-34 feet
What is a generally accepted method for locally verifying that a manual valve is
fully closed in a depressurized static piping system? - ANSWER-Attempt to turn the
valve hand wheel in the fully closed direction and verify no movement.
The purpose of backseating a manual valve in an operating system is to: -
ANSWER-isolate system pressure from the packing stuffing box to minimize
packing leakage.
2|Page
HIGH PRESSURE BOILER BLACK SEAL EXAM NEWEST
2025/2026 COMPLETE ALL QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW VERSION!
What must take place in order for combustion air to flow open automatically
during equipment operation? - ANSWER-There must be an adequate opening for
the flow of fuel gas into the confines of the boiler room to ensure proper
combustion
Furnace explosions can best be avoided by: - ANSWER-purging the furnace after
any flame interruption
What type of draft system is used to overcome resistance on power boilers
equipped with an economizer? - ANSWER-an induced draft system
What is the Btu content of natural gas? - ANSWER-100,000 Btu/therm
The term viscosity can best be defined as: - ANSWER-the point at which oil starts
to flow
A gradual increase in the stack temperature could indicate what condition in a
boiler? - ANSWER-heating surface fouling
1|Page
, High Pressure Boiler Black Seal Exam
In the ignition system on an oil burner, what causes the spark to jump the gap and
ignite the fuel? - ANSWER-a high voltage spark of 10,000V DC produced from the
transformer, jumps the gap between the electrode tips.
What are the three types of draft used in power plants? - ANSWER-natural, forced,
and induced
What would a stack gas reading of fair to good combustion look like? - ANSWER-
low oxygen and carbon monoxide, high carbon dioxide
When a discharge valve is opened to the atmosphere, the pressure on the
upstream side of the valve will: - ANSWER-decrease, and the pressure on the
downstream side will remain the same.
By N.J.A.C. 12:90 rules, what is the minimum thickness allowed for atmospheric
type blowdown tank? - ANSWER-5/16 inch
What would one standard atmosphere at 14.7 psi be equivalent to in feet of
water? - ANSWER-34 feet
What is a generally accepted method for locally verifying that a manual valve is
fully closed in a depressurized static piping system? - ANSWER-Attempt to turn the
valve hand wheel in the fully closed direction and verify no movement.
The purpose of backseating a manual valve in an operating system is to: -
ANSWER-isolate system pressure from the packing stuffing box to minimize
packing leakage.
2|Page
