DC THIRD CLASS STATIONARY BOILER
PRACTICE TEST 2026 EXAM SCRIPT WITH
VERIFIED SOLUTIONS
◉ To blowdown a boiler equipped with a quick opening and slow
opening valve on the bottom blowdown line, the_________. Answer:
quick opening valve is opened first and closed last.
◉ Hardness of water is the measurement in ppm of ________ and
________ in the water. Answer: calcium and magnesium
◉ A pump delivers 175 gallons per minute against a pressure of 55 psi;
the suction pressure is 15 psi. If a pump is 80% efficient, what is the
horsepower needed? Answer: HP=5.1 HP= (Head in Feet) x (Weight in
Lbs.)/ 33,000 x Efficiency
◉ a duplex double-acting reciprocating feed water pump has____.
Answer: two steam Pistons 2 to 2 2/2 times larger in area than the water
piston
◉ Name a technique to control the nitrous oxide emissions. Answer:
Selective Catalytic Reduction
◉ Spalling in a boiler occurs in the ____? Answer: Combustion chamber
, ◉ A technology in which solid waste is heated in an oxygen starved
atmosphere to break down the solids into a gas is called ______?
Answer: Pyrolysis
◉ What is the primary purpose of using wet scrubbers? Answer: To
remove sulfur dioxides
◉ The thermal efficiency of a boiler with a stack temperature of 750°F
and and a furnace temperature of 3200°F is_______? Answer: 75%
((3200-750)/3200) x 100
◉ ________is a water-purification process in which the water to be
treated is pressurized and applied against the surface of a semipermeable
membrane. Answer: Reverse osmosis
◉ The airflow switch at the burner fan housing______. Answer: Ensures
the primary air fan is functioning
◉ How many inches of steam space in a cylinder of an engine 12"x28"
and the stroke is 5/8 of its full travel? Answer: 1978. V=AxL
V=3.14(6x6)x28x.625= 1978
◉ What is the horsepower requirement of a pump that moves 2500 gpm
of water against a head of 475' if the pump is operating at 58%
PRACTICE TEST 2026 EXAM SCRIPT WITH
VERIFIED SOLUTIONS
◉ To blowdown a boiler equipped with a quick opening and slow
opening valve on the bottom blowdown line, the_________. Answer:
quick opening valve is opened first and closed last.
◉ Hardness of water is the measurement in ppm of ________ and
________ in the water. Answer: calcium and magnesium
◉ A pump delivers 175 gallons per minute against a pressure of 55 psi;
the suction pressure is 15 psi. If a pump is 80% efficient, what is the
horsepower needed? Answer: HP=5.1 HP= (Head in Feet) x (Weight in
Lbs.)/ 33,000 x Efficiency
◉ a duplex double-acting reciprocating feed water pump has____.
Answer: two steam Pistons 2 to 2 2/2 times larger in area than the water
piston
◉ Name a technique to control the nitrous oxide emissions. Answer:
Selective Catalytic Reduction
◉ Spalling in a boiler occurs in the ____? Answer: Combustion chamber
, ◉ A technology in which solid waste is heated in an oxygen starved
atmosphere to break down the solids into a gas is called ______?
Answer: Pyrolysis
◉ What is the primary purpose of using wet scrubbers? Answer: To
remove sulfur dioxides
◉ The thermal efficiency of a boiler with a stack temperature of 750°F
and and a furnace temperature of 3200°F is_______? Answer: 75%
((3200-750)/3200) x 100
◉ ________is a water-purification process in which the water to be
treated is pressurized and applied against the surface of a semipermeable
membrane. Answer: Reverse osmosis
◉ The airflow switch at the burner fan housing______. Answer: Ensures
the primary air fan is functioning
◉ How many inches of steam space in a cylinder of an engine 12"x28"
and the stroke is 5/8 of its full travel? Answer: 1978. V=AxL
V=3.14(6x6)x28x.625= 1978
◉ What is the horsepower requirement of a pump that moves 2500 gpm
of water against a head of 475' if the pump is operating at 58%
