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Minnesota Special Engineer Boiler License Practice
EXAM LATEST UPDATE THIS YEAR (2026-2027) ALL
300 QUESTIONS AND CORRECT ANSWERS WITH
RATIONALES
1. For the purpose of rating boiler horsepower for an Engineer's License only, how many square
feet of boiler heating surface are equivalent to one boiler horsepower?
A) 5 square feet
B) 10 square feet
C) 15 square feet
D) 20 square feet
Answer: B
For licensing purposes in Minnesota, 10 square feet of boiler heating surface is equivalent to one
boiler horsepower. This is a specific standard used for rating boiler capacity for engineer
licensing.
2. What is meant by the term "Low Pressure Boiler"?
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A) Any boiler operating below atmospheric pressure
B) Boilers operating at 15 psig steam or less, or 160 psig/250°F water or less
C) Only boilers used in residential applications
D) Boilers that operate without any pressure
Answer: B
Low-pressure boilers are defined as steam boilers operating at 15 psig or less, or hot water
boilers where pressure does not exceed 160 psig or temperature 250°F.
3. A person holding a current State of Minnesota Special Engineer's License could be in charge
of, or serve as a shift engineer in what size plant(s)?
A) Any plant regardless of size
B) High and low pressure boilers not exceeding 50 BHP total, or shift engineer in a 100 BHP
plant
C) Only low pressure boilers under 50 BHP
D) Only high pressure boilers under 100 BHP
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Answer: B
A Special Engineer may take charge of boilers not exceeding 50 BHP total, or serve as a shift
engineer in a plant not exceeding 100 BHP.
4. Special Engineer may serve as an apprentice on what size water/liquid or steam/vapor
boiler?
A) Only boilers under 50 BHP
B) Only boilers under 100 BHP
C) In any plant regardless of size under direct supervision
D) Only low pressure boilers
Answer: C
A Special Engineer may serve as an apprentice in any plant regardless of size, provided they are
under the direct supervision of a properly licensed engineer.
5. The purpose of a low water cut-off on a steam or hot water boiler is to:
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A) Shut off the feed water supply
B) Shut off the burner when a low water condition exists
C) Open the safety valve
D) Sound an alarm only
Answer: B
The low water cut-off (LWCO) shuts off the burner when the water level drops below a safe
minimum, preventing the boiler from operating without adequate water.
6. The valve or valves that must relieve all excess pressure on a steam or hot water boiler are:
A) Blowdown valves
B) Safety valve and/or ASME approved safety relief valve
C) Check valves
D) Gate valves
Answer: B
Safety valves (for steam) and ASME approved safety relief valves (for hot water) are the primary
pressure-relief devices, designed to automatically open when pressure exceeds the set point.
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Minnesota Special Engineer Boiler License Practice
EXAM LATEST UPDATE THIS YEAR (2026-2027) ALL
300 QUESTIONS AND CORRECT ANSWERS WITH
RATIONALES
1. For the purpose of rating boiler horsepower for an Engineer's License only, how many square
feet of boiler heating surface are equivalent to one boiler horsepower?
A) 5 square feet
B) 10 square feet
C) 15 square feet
D) 20 square feet
Answer: B
For licensing purposes in Minnesota, 10 square feet of boiler heating surface is equivalent to one
boiler horsepower. This is a specific standard used for rating boiler capacity for engineer
licensing.
2. What is meant by the term "Low Pressure Boiler"?
1
, Page 2 of 173
A) Any boiler operating below atmospheric pressure
B) Boilers operating at 15 psig steam or less, or 160 psig/250°F water or less
C) Only boilers used in residential applications
D) Boilers that operate without any pressure
Answer: B
Low-pressure boilers are defined as steam boilers operating at 15 psig or less, or hot water
boilers where pressure does not exceed 160 psig or temperature 250°F.
3. A person holding a current State of Minnesota Special Engineer's License could be in charge
of, or serve as a shift engineer in what size plant(s)?
A) Any plant regardless of size
B) High and low pressure boilers not exceeding 50 BHP total, or shift engineer in a 100 BHP
plant
C) Only low pressure boilers under 50 BHP
D) Only high pressure boilers under 100 BHP
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Answer: B
A Special Engineer may take charge of boilers not exceeding 50 BHP total, or serve as a shift
engineer in a plant not exceeding 100 BHP.
4. Special Engineer may serve as an apprentice on what size water/liquid or steam/vapor
boiler?
A) Only boilers under 50 BHP
B) Only boilers under 100 BHP
C) In any plant regardless of size under direct supervision
D) Only low pressure boilers
Answer: C
A Special Engineer may serve as an apprentice in any plant regardless of size, provided they are
under the direct supervision of a properly licensed engineer.
5. The purpose of a low water cut-off on a steam or hot water boiler is to:
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, Page 4 of 173
A) Shut off the feed water supply
B) Shut off the burner when a low water condition exists
C) Open the safety valve
D) Sound an alarm only
Answer: B
The low water cut-off (LWCO) shuts off the burner when the water level drops below a safe
minimum, preventing the boiler from operating without adequate water.
6. The valve or valves that must relieve all excess pressure on a steam or hot water boiler are:
A) Blowdown valves
B) Safety valve and/or ASME approved safety relief valve
C) Check valves
D) Gate valves
Answer: B
Safety valves (for steam) and ASME approved safety relief valves (for hot water) are the primary
pressure-relief devices, designed to automatically open when pressure exceeds the set point.
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