Boiler Exam Practice Tests 2026 | Study Guide & Sample Questions

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Boiler Exam Practice Tests (NEW UPDATED VERSION) LATEST
ACTUAL EXAM QUESTIONS AND CORRECT ANSWERS (VERIFIED
QUESTIONS AND ANSWERS)- GUARANTEED PASS A+ UPDATED 2026




removes sludge and sediment from the mud drum - CORRECT ANSWER
The bottom blowdown on a boiler ___.


QUESTION : outside diameter - CORRECT ANSWER Boiler tubes are
sized using the ___.


QUESTION : tin - CORRECT ANSWER A boiler fusible plug is brass or
bronze with a core of ___.


QUESTION : hairline cracks in the refractory - CORRECT ANSWER
Spalling in a boiler refers to ___.


QUESTION : 34.5 - CORRECT ANSWER Boiler horsepower is the
evaporation of ___ lb of water/hr from and at a feedwater temperature of 212°F.


QUESTION : steam temperature - CORRECT ANSWER A siphon
installed between the boiler and the pressure gauge protects the Bourdon tube
from___.




2026 2027 GRADED A+

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QUESTION : 10 to 11.5 - CORRECT ANSWER The pH of the boiler
water should be ___.


QUESTION : steam leaving the boiler - CORRECT ANSWER The
boiler superheater raises the temperature of the ___.


QUESTION : feedwater - CORRECT ANSWER An economizer is used
to preheat ___.


QUESTION : oily waste rags - CORRECT ANSWER Fires caused by
spontaneous combustion would probably start in the ___.


QUESTION : dirty strainers - CORRECT ANSWER A high suction
reading on the fuel oil pressure gauge indicates ___.


QUESTION : try cock - CORRECT ANSWER The ___ is a secondary
means of determining boiler water level.


QUESTION : pyrometer - CORRECT ANSWER A(n) ___ is used to
measure furnace temperature.


QUESTION : 1 ½ - CORRECT ANSWER The range of a boiler pressure
gauge must not be less than ___ times the safety valve setting.


QUESTION : prevent formation of scale - CORRECT ANSWER Boiler
feedwater is chemically treated to ___.


2026 2027 GRADED A+

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QUESTION : deadweight tester - CORRECT ANSWER Pressure
gauges are calibrated with a(n) ___.


QUESTION : inside tube surface - CORRECT ANSWER In a firetube
boiler, soot settles on the ___.


QUESTION : complete - CORRECT ANSWER Carbon dioxide in the
flue gas is a sign of ___ combustion.


QUESTION : incomplete - CORRECT ANSWER Carbon monoxide in
the flue gas is a sign of ___ combustion.


QUESTION : Globe - CORRECT ANSWER ___ valves should be used
for throttling service.


QUESTION : a dirty heating surface - CORRECT ANSWER A gradual
increase in chimney temperature indicates ___.


QUESTION : 1 ½ - CORRECT ANSWER The pressure applied on the
boiler during a hydrostatic test is ___ times the MAWP.


QUESTION : 6 - CORRECT ANSWER Boiler safety valve capacity must
be such that the steam pressure can never go higher than ___% above the
MAWP.




2026 2027 GRADED A+

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QUESTION : decreased - CORRECT ANSWER As fuel oil is heated, its
viscosity is ___.


QUESTION : 6 - CORRECT ANSWER No. ___ fuel oil has the highest
Btu content per gallon.


QUESTION : T - CORRECT ANSWER T/F All steam boilers must have
one or more safety valves.


QUESTION : T - CORRECT ANSWER T/F An open feedwater heater
vents gases to the atmosphere.


QUESTION : F - CORRECT ANSWER T/F A hydrostatic test will
determine whether a steam boiler has sufficient relieving capacity.


QUESTION : T - CORRECT ANSWER T/F When boilers are set in
battery, the main steam stop valves, bottom blowdown valves, and feedwater
valves should be locked closed before anyone enters the boiler drums.


QUESTION : F - CORRECT ANSWER T/F Open and closed feedwater
heaters are never used at the same time.


QUESTION : T - CORRECT ANSWER T/F In an open feedwater heater,
the water and steam come into direct contact; in a closed feedwater heater, the
water and steam are separated.




2026 2027 GRADED A+