Page 1 of 164
3RD CLASS STATIONARY STEAM ENGINEER
LICENSE DC 1ST CLASS BOILER ACTUAL
EXAM PREP/STUDY GUIDE/TEST BANK 2026
ALL QUESTIONS AND CORRECT DETAILED
ANSWERS ALREADY A GRADED WITH EXPERT
FEEDBACK|NEW AND REVISED|HIGHLY
RECOMMENDED BY EXPERTS
When is a pump steam bound? - ANSWER- Steam bound indicates the
water is too hot for the suction of the pump, and the water flashes into
steam with reduction of pressure.
Which condition is a boiler not protected against? - ANSWER- under
pressure
Which by product has the lowest heating value? - ANSWER- blast
furnace gas
What is the last protection against overheating in a boiler? - ANSWER-
LWCO (Low Water Cut Off)
In an open type expansion tank how high should the tank be mounted? -
ANSWER- at least 4 feet above the highest heating element
Which element does not take an actual action in the combustion process?
- ANSWER- nitrogen
,Page 2 of 164
Immediately after a repair to a refrigeration system what is used to
remove moisture from the system? - ANSWER- vacuum pump
The boiler steam line is 450 feet long. During start up the pipe is heated
from 70F to 360F. how many inches the pipe will expand? - ANSWER-
10.18 Formula: Exp in = (T1 - T2) x L x 0.0000065= 360 - 70 x
(450x12) x 0.0000065
= 290 x 5400 x 0.0000065 = 10.18
What would you add to a boiler, if you are needed to the protect the
refractory from Excess heat and to increase the capacity of the boiler? -
ANSWER- Riser Tubes
A condensate tank has a lot of steam existing from its vent it is
registering 20 F higher Than normal. What could be the reason? -
ANSWER- Steam Trap Failing Open
What kind of valve allows a boiler to be "cut in online" when the main
isolation valve is Open or closed? - ANSWER- top check valve
In a siphon, what is the water seal between the boiler and the pressure
controls called? - ANSWER- condensate
What is the formula to find a volume of cylinder? - ANSWER- Formula
or equation is: V = Area of a circle X High or Length.
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Where V: volume
Area of a circle is: A = (D² X 0.7854)
For example:
What is the volume of a cylinder tank that has a 15" diameter and 30"
high?
V = (15x15x0.7854) x 30
V = 176.715 x 30
V = 5301.45 in³ " 15
To get gallons
G = 5301.45 ÷ 231
G = 22.95
30"
How many cubic inches are in a gallon? - ANSWER- 231 cubic inches
How to calculate boiler horsepower? - ANSWER- BHP= lb/hr x factor
of evaporation (1.08) divided by 34.5
What is the circumference of a circle with a 10" diameter? - ANSWER-
Formula = C = D x 3.14
C = 10 x 3.14
C = 31.4"
, Page 4 of 164
What is the circumference of a circle with a 26" diameter? - ANSWER-
Formula = C = D x 3.14
C = 26 x 3.14
C = 81.64"
What is the area of a circle with a 10" diameter? - ANSWER- Formula =
A = D2 x 0.7854
A = 10 x 10 x 0.7854
A = 78.54 in2
What is the area of a circle with a 35" diameter? - ANSWER- Formula =
A = D2 x 0.7854
A = 35 x 35 x 0.7854
A = 962.11 in2
What is the area of a triangle with a base of 20" and a height of 18"? -
ANSWER- Formula = A = 1⁄2 x Base x Height
A = 1⁄2 x 20 x 18
A = 180 in2
What is the area of a triangle with a base of 45" and a height of 26"? -
ANSWER- A = 1⁄2 x Base x Height
A = 1⁄2 x 45 x 26A = 585 in2
3RD CLASS STATIONARY STEAM ENGINEER
LICENSE DC 1ST CLASS BOILER ACTUAL
EXAM PREP/STUDY GUIDE/TEST BANK 2026
ALL QUESTIONS AND CORRECT DETAILED
ANSWERS ALREADY A GRADED WITH EXPERT
FEEDBACK|NEW AND REVISED|HIGHLY
RECOMMENDED BY EXPERTS
When is a pump steam bound? - ANSWER- Steam bound indicates the
water is too hot for the suction of the pump, and the water flashes into
steam with reduction of pressure.
Which condition is a boiler not protected against? - ANSWER- under
pressure
Which by product has the lowest heating value? - ANSWER- blast
furnace gas
What is the last protection against overheating in a boiler? - ANSWER-
LWCO (Low Water Cut Off)
In an open type expansion tank how high should the tank be mounted? -
ANSWER- at least 4 feet above the highest heating element
Which element does not take an actual action in the combustion process?
- ANSWER- nitrogen
,Page 2 of 164
Immediately after a repair to a refrigeration system what is used to
remove moisture from the system? - ANSWER- vacuum pump
The boiler steam line is 450 feet long. During start up the pipe is heated
from 70F to 360F. how many inches the pipe will expand? - ANSWER-
10.18 Formula: Exp in = (T1 - T2) x L x 0.0000065= 360 - 70 x
(450x12) x 0.0000065
= 290 x 5400 x 0.0000065 = 10.18
What would you add to a boiler, if you are needed to the protect the
refractory from Excess heat and to increase the capacity of the boiler? -
ANSWER- Riser Tubes
A condensate tank has a lot of steam existing from its vent it is
registering 20 F higher Than normal. What could be the reason? -
ANSWER- Steam Trap Failing Open
What kind of valve allows a boiler to be "cut in online" when the main
isolation valve is Open or closed? - ANSWER- top check valve
In a siphon, what is the water seal between the boiler and the pressure
controls called? - ANSWER- condensate
What is the formula to find a volume of cylinder? - ANSWER- Formula
or equation is: V = Area of a circle X High or Length.
,Page 3 of 164
Where V: volume
Area of a circle is: A = (D² X 0.7854)
For example:
What is the volume of a cylinder tank that has a 15" diameter and 30"
high?
V = (15x15x0.7854) x 30
V = 176.715 x 30
V = 5301.45 in³ " 15
To get gallons
G = 5301.45 ÷ 231
G = 22.95
30"
How many cubic inches are in a gallon? - ANSWER- 231 cubic inches
How to calculate boiler horsepower? - ANSWER- BHP= lb/hr x factor
of evaporation (1.08) divided by 34.5
What is the circumference of a circle with a 10" diameter? - ANSWER-
Formula = C = D x 3.14
C = 10 x 3.14
C = 31.4"
, Page 4 of 164
What is the circumference of a circle with a 26" diameter? - ANSWER-
Formula = C = D x 3.14
C = 26 x 3.14
C = 81.64"
What is the area of a circle with a 10" diameter? - ANSWER- Formula =
A = D2 x 0.7854
A = 10 x 10 x 0.7854
A = 78.54 in2
What is the area of a circle with a 35" diameter? - ANSWER- Formula =
A = D2 x 0.7854
A = 35 x 35 x 0.7854
A = 962.11 in2
What is the area of a triangle with a base of 20" and a height of 18"? -
ANSWER- Formula = A = 1⁄2 x Base x Height
A = 1⁄2 x 20 x 18
A = 180 in2
What is the area of a triangle with a base of 45" and a height of 26"? -
ANSWER- A = 1⁄2 x Base x Height
A = 1⁄2 x 45 x 26A = 585 in2
