DC 3rd CLASS STATIONARY STEAM ENGINEER
LICENSE PREP, STATIONARY ENGINEER,
STATION ENGINEER EXAM, DC 1st CLASS
BOILER 2026/2027 WITH ACTUAL CORRECT
QUESTIONS AND VERIFIED DETAILED
ANSWERS |FREQUENTLY TESTED QUESTIONS
AND SOLUTION|ALREADY GRADED
A+|NEWEST|JUST RELEASED |GUARANTEED
PASS!!
What is the heart of a refrigeration system?
compressor
Which coal has the biggest level of fixed carbon content?
Anthracite = 14,000
What is the cause of high excess in a condensate return tank with temperature up to 20
degrees above normal?
Steam traps are stuck open
Water inlet into a building is 100 psig, if no booster pumps are used. What will be the
Pressure on the 10th floor, if the building is 10 feet per floor?
43.3 2.31 = 1 psi, 100 psi = 100/2.31 = 43.3 psi
Where is the total hardness of a softener reading .5 grains?
( 17.1 x .5 = 8.6 )
How many BTUs are raise 2 lbs of water from 32F to 212F?
360 btu 212 -32 = 180 x 2 = 360btu
1|Page
,A stoker that uses a feed RAM is a?
underfeed stoker
Water scales can be removed by boiling or raising water temperature is?
temporary
What is the proper way of testing a safety valve?
Allow pressure to build up to 75% before lifting the test level
When a safety valve discharges, it should relieve the boiler so that the pressure does not
Exceed more than ______?
6%
When conducting an evaporation test, the operator must secure what?
The feed water to the boiler
What steam trap has one movable device that rises to allow steam through and resets on
condensate?
Float Trap
What part in a refrigeration cycle discharges, high temperature pressure of vapor?
Condenser
What part in a refrigeration cycle discharges low pressure liquid?
Expansion Valve
The Chie f heat producing elements in fuels contents are?
Carbon and Hydrogen
Proximate analysis reports which of the following?
The volatile matter, percent of moisture, fixed carbon and ash
2|Page
,What is the maximum range of pressure settings for all the saturated steam safety valves
on boilers?
10% of the highest set valve
What type of valve would you use nearest the boiler in a blow down line?
quick opening
What type of valve would you use to control blow down?
slow opening
How is a boiler hydrostatic test performed?
fill the boiler with 70ºF of water and raise the pressure to 1.5 MAWP
A 3 element feed regulator senses what to control water flow?
water level, steam flow, water flow
On/off controls that activate devices using a one variable (i.e. pressure) are called?
discrete controls
Controls which use a quantity measured over a range of dynamic values are?
analog
What type of valve would not be a good choice if sediment is present in a system?
globe valve
A proximate analysis of coal will not report what?
percent of various chemical elements
A Boiler shall be designed and constructed in accordance with?
ASME CSD-1
Discrete control when used for steam pressure is what type of control?
3|Page
, on/off and stop/go
The purpose of the condenser in a refrigerant system is to?
change the refrigerant from vapor to a liquid state
The __ is where the liquid refrigerant turns into gas and absorbs latent heat?
evaporator
The __ removes moisture from a refrigeration system.
filter drier
The oil in a refrigeration system is used for
Cooling and lubrication
When is a pump steam bound?
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?
under pressure
Which by product has the lowest heating value?
blast furnace gas
What is the last protection against overheating in a boiler?
LWCO (Low Water Cut Off)
In an open type expansion tank how high should the tank be mounted?
at least 4 feet above the highest heating element
Which element does not take an actual action in the combustion process?
nitrogen
4|Page
LICENSE PREP, STATIONARY ENGINEER,
STATION ENGINEER EXAM, DC 1st CLASS
BOILER 2026/2027 WITH ACTUAL CORRECT
QUESTIONS AND VERIFIED DETAILED
ANSWERS |FREQUENTLY TESTED QUESTIONS
AND SOLUTION|ALREADY GRADED
A+|NEWEST|JUST RELEASED |GUARANTEED
PASS!!
What is the heart of a refrigeration system?
compressor
Which coal has the biggest level of fixed carbon content?
Anthracite = 14,000
What is the cause of high excess in a condensate return tank with temperature up to 20
degrees above normal?
Steam traps are stuck open
Water inlet into a building is 100 psig, if no booster pumps are used. What will be the
Pressure on the 10th floor, if the building is 10 feet per floor?
43.3 2.31 = 1 psi, 100 psi = 100/2.31 = 43.3 psi
Where is the total hardness of a softener reading .5 grains?
( 17.1 x .5 = 8.6 )
How many BTUs are raise 2 lbs of water from 32F to 212F?
360 btu 212 -32 = 180 x 2 = 360btu
1|Page
,A stoker that uses a feed RAM is a?
underfeed stoker
Water scales can be removed by boiling or raising water temperature is?
temporary
What is the proper way of testing a safety valve?
Allow pressure to build up to 75% before lifting the test level
When a safety valve discharges, it should relieve the boiler so that the pressure does not
Exceed more than ______?
6%
When conducting an evaporation test, the operator must secure what?
The feed water to the boiler
What steam trap has one movable device that rises to allow steam through and resets on
condensate?
Float Trap
What part in a refrigeration cycle discharges, high temperature pressure of vapor?
Condenser
What part in a refrigeration cycle discharges low pressure liquid?
Expansion Valve
The Chie f heat producing elements in fuels contents are?
Carbon and Hydrogen
Proximate analysis reports which of the following?
The volatile matter, percent of moisture, fixed carbon and ash
2|Page
,What is the maximum range of pressure settings for all the saturated steam safety valves
on boilers?
10% of the highest set valve
What type of valve would you use nearest the boiler in a blow down line?
quick opening
What type of valve would you use to control blow down?
slow opening
How is a boiler hydrostatic test performed?
fill the boiler with 70ºF of water and raise the pressure to 1.5 MAWP
A 3 element feed regulator senses what to control water flow?
water level, steam flow, water flow
On/off controls that activate devices using a one variable (i.e. pressure) are called?
discrete controls
Controls which use a quantity measured over a range of dynamic values are?
analog
What type of valve would not be a good choice if sediment is present in a system?
globe valve
A proximate analysis of coal will not report what?
percent of various chemical elements
A Boiler shall be designed and constructed in accordance with?
ASME CSD-1
Discrete control when used for steam pressure is what type of control?
3|Page
, on/off and stop/go
The purpose of the condenser in a refrigerant system is to?
change the refrigerant from vapor to a liquid state
The __ is where the liquid refrigerant turns into gas and absorbs latent heat?
evaporator
The __ removes moisture from a refrigeration system.
filter drier
The oil in a refrigeration system is used for
Cooling and lubrication
When is a pump steam bound?
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?
under pressure
Which by product has the lowest heating value?
blast furnace gas
What is the last protection against overheating in a boiler?
LWCO (Low Water Cut Off)
In an open type expansion tank how high should the tank be mounted?
at least 4 feet above the highest heating element
Which element does not take an actual action in the combustion process?
nitrogen
4|Page
