MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
1.a question: an answer
2.what are the conditions necessary for good combustion?
a) low sulfur content
b) Thermal, thermocoupler, tubular
c) turbulence, temperature, time 3T's:
ANS>>c) turbulence, temperature, time 3T's
3.why is secondary air necessary in hand fired boilers?
a) Necessary to burn the combustible gases
b) if primary air should fail
c) used only if sulfur content is high:
ANS>>a) Necessary to burn the combustible gases
4.when pressure increases on steam from a given amount of water
what happens to its volume and latent heat?
a) increases
b) decreases
c) remains the same:
ANS>> b) decreases
5.when pressure increases on steam from a given amount of water
what happens to its temperature?
a) increases
b) decreases
c) remains the same:
ANS>>a) increases
6.when carbon monoxide (co) is formed and carbon dioxide (co2) is very
high what does it generally signify?
a) More "under the fire air" is needed
b) less "under the fire air" is required
c) more "over the fire" air is needed
d) less "over the fire" is needed less:
ANS>> c) more "over the fire" air is needed
7.excess air is an expression that refers to:
,MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
a) overabundance of air
b) theoretical amount of air
c) air supplied above that theoretically required:
ANS>> c) air supplied above that theoretically required
8.a good percentage of carbon dioxide when burning oil is:
a) 12%
b) 8 %
c) 10%:
ANS>> a) 12%
9.what is draft on a boiler in operation?
a) Flow of gases through boiler
b) difference in pressure between atmosphere and furnace or firebox
c) difference between atmospheric pressure and breeching:
ANS>> b) difference in pressure between atmosphere and
furnace or firebox
,MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
10.which has greater heating value per pound?
a) oil
b) coal:
ANS>> a) oil (18000 - 19500
BTU) (coal has (6900 - 12910
BTU))
11.heavy oil must be heated before entering the burner to:
a) increase carbon content
b) decreased sulfur content
c) get proper atomization:
ANS>> c) get proper atomization
12.why should a daily log be kept of flue gas temperature?
a) Valuable information in case of explosion
b) superintendent files them
c) change an operation, causing heat loss, can be detected:
ANS>>c) change an operation, causing heat loss, can be
detected
13.find SWP of a boiler 72 inches in diameter, thickness of one-half inch,
tensile strength of 55,000 pounds, quadruple riveted butt and strap joint
(.94) factor of safety 5:
a) 14.3
b) 143.6
c) 1436:
ANS>> b) 143.6
14.the total heat of steam is 1,188 BTUs, and feed water temperature is
182 degrees Fahrenheit. What is the factor of evaporation?
a) 107
b) 10.7
c) 1.07:
ANS>> c) 1.07
15.why would viscosity be important in fuel oil?
,MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
a) more heat is recovered in water
b) has more volatile hydrocarbons
c) affects ease with which it can be handled:
ANS>> c) effects ease with which it can be handled
16.why is too much air objectionable?
a) Cost too high
b) loss of efficiency
c) corrosive effect:
ANS>> b) loss of efficiency
17.what is a fyrite used for?
a) flue gas analyzer
b) combustion programmer
c) water analysis:
ANS>> a) flue gas analyzer
18.absolute pressure is (ABS):
a) atmospheric pressure - gauge pressure
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
1.a question: an answer
2.what are the conditions necessary for good combustion?
a) low sulfur content
b) Thermal, thermocoupler, tubular
c) turbulence, temperature, time 3T's:
ANS>>c) turbulence, temperature, time 3T's
3.why is secondary air necessary in hand fired boilers?
a) Necessary to burn the combustible gases
b) if primary air should fail
c) used only if sulfur content is high:
ANS>>a) Necessary to burn the combustible gases
4.when pressure increases on steam from a given amount of water
what happens to its volume and latent heat?
a) increases
b) decreases
c) remains the same:
ANS>> b) decreases
5.when pressure increases on steam from a given amount of water
what happens to its temperature?
a) increases
b) decreases
c) remains the same:
ANS>>a) increases
6.when carbon monoxide (co) is formed and carbon dioxide (co2) is very
high what does it generally signify?
a) More "under the fire air" is needed
b) less "under the fire air" is required
c) more "over the fire" air is needed
d) less "over the fire" is needed less:
ANS>> c) more "over the fire" air is needed
7.excess air is an expression that refers to:
,MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
a) overabundance of air
b) theoretical amount of air
c) air supplied above that theoretically required:
ANS>> c) air supplied above that theoretically required
8.a good percentage of carbon dioxide when burning oil is:
a) 12%
b) 8 %
c) 10%:
ANS>> a) 12%
9.what is draft on a boiler in operation?
a) Flow of gases through boiler
b) difference in pressure between atmosphere and furnace or firebox
c) difference between atmospheric pressure and breeching:
ANS>> b) difference in pressure between atmosphere and
furnace or firebox
,MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
10.which has greater heating value per pound?
a) oil
b) coal:
ANS>> a) oil (18000 - 19500
BTU) (coal has (6900 - 12910
BTU))
11.heavy oil must be heated before entering the burner to:
a) increase carbon content
b) decreased sulfur content
c) get proper atomization:
ANS>> c) get proper atomization
12.why should a daily log be kept of flue gas temperature?
a) Valuable information in case of explosion
b) superintendent files them
c) change an operation, causing heat loss, can be detected:
ANS>>c) change an operation, causing heat loss, can be
detected
13.find SWP of a boiler 72 inches in diameter, thickness of one-half inch,
tensile strength of 55,000 pounds, quadruple riveted butt and strap joint
(.94) factor of safety 5:
a) 14.3
b) 143.6
c) 1436:
ANS>> b) 143.6
14.the total heat of steam is 1,188 BTUs, and feed water temperature is
182 degrees Fahrenheit. What is the factor of evaporation?
a) 107
b) 10.7
c) 1.07:
ANS>> c) 1.07
15.why would viscosity be important in fuel oil?
,MN BOILERS TEST BANK – COMPLETE BOILER LICENSE
EXAM QUESTIONS & ANSWERS (2025/2026 UPDATE)
a) more heat is recovered in water
b) has more volatile hydrocarbons
c) affects ease with which it can be handled:
ANS>> c) effects ease with which it can be handled
16.why is too much air objectionable?
a) Cost too high
b) loss of efficiency
c) corrosive effect:
ANS>> b) loss of efficiency
17.what is a fyrite used for?
a) flue gas analyzer
b) combustion programmer
c) water analysis:
ANS>> a) flue gas analyzer
18.absolute pressure is (ABS):
a) atmospheric pressure - gauge pressure
