1 | Page
Stationary Engineer Questions and Correct
Answers
How much clearance from the top of the boiler is needed for a HP
boiler that produces 70000 lbs of steam? Ans: 7 feet
On a gas fired boiler what is the proper gas to air mixture Ans:
30%-70% and in special arrangements it can be as high as 100% .
ANSWER CHAPTER 11 remember%
What is the total hardness in a system that was found to have
calcium hardness of 60ppm and magnesium hardness of 18ppm
and carbon hardness of 12 ppm? Ans: TH=(Ca x 2.5) + (Mg x
4.1)\nTH=(60 x 2.5) + (18 x 4.1)\nTH= 150+73.8 =( 223.8 PPM)
How often should a complete external inspection of the boiler be
done? Ans: Once a Shift
With 24 hr operation how often do you check the water level? Ans:
Once per shift
How often do you check the LWCO? Ans: Once per shift
How often do you check the High Limit Switch? Ans: Annually
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, 2 | Page
A 2" pipe was found to be delivering water at 100 psia at 1040ft
per second. How many gallons per hour will it deliver? Ans: GPM=
V (diameter squared) divided by .4085 ANSWER pg 469 BOG
What controls the amount of blowback on a safety valve? Ans:
Blowback ring or adjusting ring
On a open air expansion tank hot water boiler system; how high
should it be mounted? Ans: (4 Feet ) above the highest heating
element.
What is the minimum top clearance of boilers with manholes? Ans:
5 feet
Package boilers; steam heating boilers and hot water heating
boilers shall have a minimum clearance of? Ans: 2 feet from
ceiling. Code chapter 10 page76
Most important safety device on a boiler? Ans: Safety relief valve
What does a Black Liquor Boiler do? Ans: Black Liquor is the by
product of wood pulp processing in the paper making industry.
What does Black liquor boiler known for? Ans: Steam generation
and recovery of soda ash
Maximum line voltage for control on a boiler? Ans: 150 volts
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, 3 | Page
Under what code are boilers designed and constructed? Ans:
ASME- CSD 1
How many low water cut offs are needed per code for a hot water
system when a boiler has inputs greater than 400,000 btu per hr
Ans: 1 LWCO is needed.
What is the minimum and maximum size for a safety valve per
code for boilers? Ans: Minimum 3/4" and Maximum 4 1/2"
What stamp is put on a boiler after repairs? Ans: "R"
What is the equalizing system used for? Ans: The equalizing
system is for warming up the steam lead.
A blowdown valve is located at the lowest water space of a boiler
for three purposes Ans: 1. to remove precipitated sludge or loose
scale \n2. To permit rapid lowering of the boiler water if it has
become too high accidentally \n3. As a means of removing water
from the boiler so that fresh water may be added to keep the
concentration of solids below the point where difficulties may be
experienced.
In the old power boiler which type of feed-water regulators were
not used? Ans: Electronic
After opening a boiler for repairs how much oxygen is needed?
Ans: 19%
© 2025 All rights reserved
, 4 | Page
What is the first thing you do when shutting down a boiler? Ans:
Turn off (extinguish fire)
What is the legal limit of acceptable asbestos particles ? Ans: 0.1
fibers per cubic centimeter
What is CREEP? Ans: Creep is defined as the slow deformation of
material with time; with the deformation taking place at elevated
temperatures with no increase in stress.
What is the BTU content of Anthracite coal? Ans: 14000 btu/lb
What substance transfers electrical current in a photocell? Ans:
Electricity will flow when the CADMIUM is exposed to sufficient
light.
What device acts as a check valve in both directions and keeps
pumps primed? Ans: FOOT VALVES are used for pumps under
suction pressure to prevent backflow primed? on the suction line.
What protects boilers from explosion in the furnace? Ans: A flame
guard system is an arrangement of flame detection system;
interlocks; and relays which will sense the presence of a proper
flame in a furnace and cause fuel to be shut off to the furnace if a
hazardous condition develops (improper flame or combustion).
What size pipe is used as a header in a boiler operating at 100psi?
Ans: 6 inches
© 2025 All rights reserved
Stationary Engineer Questions and Correct
Answers
How much clearance from the top of the boiler is needed for a HP
boiler that produces 70000 lbs of steam? Ans: 7 feet
On a gas fired boiler what is the proper gas to air mixture Ans:
30%-70% and in special arrangements it can be as high as 100% .
ANSWER CHAPTER 11 remember%
What is the total hardness in a system that was found to have
calcium hardness of 60ppm and magnesium hardness of 18ppm
and carbon hardness of 12 ppm? Ans: TH=(Ca x 2.5) + (Mg x
4.1)\nTH=(60 x 2.5) + (18 x 4.1)\nTH= 150+73.8 =( 223.8 PPM)
How often should a complete external inspection of the boiler be
done? Ans: Once a Shift
With 24 hr operation how often do you check the water level? Ans:
Once per shift
How often do you check the LWCO? Ans: Once per shift
How often do you check the High Limit Switch? Ans: Annually
© 2025 All rights reserved
, 2 | Page
A 2" pipe was found to be delivering water at 100 psia at 1040ft
per second. How many gallons per hour will it deliver? Ans: GPM=
V (diameter squared) divided by .4085 ANSWER pg 469 BOG
What controls the amount of blowback on a safety valve? Ans:
Blowback ring or adjusting ring
On a open air expansion tank hot water boiler system; how high
should it be mounted? Ans: (4 Feet ) above the highest heating
element.
What is the minimum top clearance of boilers with manholes? Ans:
5 feet
Package boilers; steam heating boilers and hot water heating
boilers shall have a minimum clearance of? Ans: 2 feet from
ceiling. Code chapter 10 page76
Most important safety device on a boiler? Ans: Safety relief valve
What does a Black Liquor Boiler do? Ans: Black Liquor is the by
product of wood pulp processing in the paper making industry.
What does Black liquor boiler known for? Ans: Steam generation
and recovery of soda ash
Maximum line voltage for control on a boiler? Ans: 150 volts
© 2025 All rights reserved
, 3 | Page
Under what code are boilers designed and constructed? Ans:
ASME- CSD 1
How many low water cut offs are needed per code for a hot water
system when a boiler has inputs greater than 400,000 btu per hr
Ans: 1 LWCO is needed.
What is the minimum and maximum size for a safety valve per
code for boilers? Ans: Minimum 3/4" and Maximum 4 1/2"
What stamp is put on a boiler after repairs? Ans: "R"
What is the equalizing system used for? Ans: The equalizing
system is for warming up the steam lead.
A blowdown valve is located at the lowest water space of a boiler
for three purposes Ans: 1. to remove precipitated sludge or loose
scale \n2. To permit rapid lowering of the boiler water if it has
become too high accidentally \n3. As a means of removing water
from the boiler so that fresh water may be added to keep the
concentration of solids below the point where difficulties may be
experienced.
In the old power boiler which type of feed-water regulators were
not used? Ans: Electronic
After opening a boiler for repairs how much oxygen is needed?
Ans: 19%
© 2025 All rights reserved
, 4 | Page
What is the first thing you do when shutting down a boiler? Ans:
Turn off (extinguish fire)
What is the legal limit of acceptable asbestos particles ? Ans: 0.1
fibers per cubic centimeter
What is CREEP? Ans: Creep is defined as the slow deformation of
material with time; with the deformation taking place at elevated
temperatures with no increase in stress.
What is the BTU content of Anthracite coal? Ans: 14000 btu/lb
What substance transfers electrical current in a photocell? Ans:
Electricity will flow when the CADMIUM is exposed to sufficient
light.
What device acts as a check valve in both directions and keeps
pumps primed? Ans: FOOT VALVES are used for pumps under
suction pressure to prevent backflow primed? on the suction line.
What protects boilers from explosion in the furnace? Ans: A flame
guard system is an arrangement of flame detection system;
interlocks; and relays which will sense the presence of a proper
flame in a furnace and cause fuel to be shut off to the furnace if a
hazardous condition develops (improper flame or combustion).
What size pipe is used as a header in a boiler operating at 100psi?
Ans: 6 inches
© 2025 All rights reserved
