4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
A hot water boiler operating control (Aquastat) may be a pressure
switch:
*A* that is normally open
*B* that responds to the expansion and contraction of boiler water
*C* operated by a filled system thermometer
*D* that is sensitive to steam pressure -
correct answer ✅C
A light fuel oil flame should
*A* impinge on the refractory, to stabilize ignition.
*B* be bright yellow, with orange at the tips of the flame.
*C* be predominantly blue, with orange at the tips of the flame.
*D* be bright yellow, with smoke at the tips of the flame. -
correct answer ✅B
The purpose of the pipe siphon installed between the boiler and
the pressure gauge is to prevent:
,4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
*A* Air from entering the gauge
*B* Water from entering the gauge
*C* Hot steam from entering the gauge
*D* Air from entering the boiler -
correct answer ✅C
Boilers should be warmed up
*A* with maximum combustion air, to prevent smoking
*B* rapidly, so the metal heats up faster
*C* slowly, to minimize differential expansion and thermal shock
*D* using only the pilot burner. -
correct answer ✅C
The discharge pipe from a boiler safety valve is supported
independently of the safety valve:
,4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
*A* Because the steam drum cannot support the extra mass of the
discharge pipe
*B* So the discharge pipe can drain more easily
*C* So the discharge pipe can expand without putting force on the
safety valve
*D* To prevent leakage at the pipe joint -
correct answer ✅C
A modulating control steam heating boiler:
*A* Is always fully automatic
*B* Will have a narrow operating pressure range
*C* Maintains a steadier boiler pressure than multi-position control
*D* Will have a constant combustion air flow rate -
correct answer ✅C
Which of the following is a desiccant used for dry layup?
*A* Silicone Gel
, 4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
*B* Lime soda
*C* Quick lime
*D* Soda ash -
correct answer ✅C
The prime importance of boiler fittings is:
*A* Economics
*B* To satisfy regulations
*C* Safety & efficiency
*D* Convenience -
correct answer ✅C
If a new boiler is not boiled out correctly, the result may be:
*A* Refractory damage
*B* Excessive waterside corrosion
*C* Excessively high water circulation rates
Knowledge Checks Exam Questions &
Answers (Grade A+)
A hot water boiler operating control (Aquastat) may be a pressure
switch:
*A* that is normally open
*B* that responds to the expansion and contraction of boiler water
*C* operated by a filled system thermometer
*D* that is sensitive to steam pressure -
correct answer ✅C
A light fuel oil flame should
*A* impinge on the refractory, to stabilize ignition.
*B* be bright yellow, with orange at the tips of the flame.
*C* be predominantly blue, with orange at the tips of the flame.
*D* be bright yellow, with smoke at the tips of the flame. -
correct answer ✅B
The purpose of the pipe siphon installed between the boiler and
the pressure gauge is to prevent:
,4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
*A* Air from entering the gauge
*B* Water from entering the gauge
*C* Hot steam from entering the gauge
*D* Air from entering the boiler -
correct answer ✅C
Boilers should be warmed up
*A* with maximum combustion air, to prevent smoking
*B* rapidly, so the metal heats up faster
*C* slowly, to minimize differential expansion and thermal shock
*D* using only the pilot burner. -
correct answer ✅C
The discharge pipe from a boiler safety valve is supported
independently of the safety valve:
,4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
*A* Because the steam drum cannot support the extra mass of the
discharge pipe
*B* So the discharge pipe can drain more easily
*C* So the discharge pipe can expand without putting force on the
safety valve
*D* To prevent leakage at the pipe joint -
correct answer ✅C
A modulating control steam heating boiler:
*A* Is always fully automatic
*B* Will have a narrow operating pressure range
*C* Maintains a steadier boiler pressure than multi-position control
*D* Will have a constant combustion air flow rate -
correct answer ✅C
Which of the following is a desiccant used for dry layup?
*A* Silicone Gel
, 4B Power Engineering - Final - Nait
Knowledge Checks Exam Questions &
Answers (Grade A+)
*B* Lime soda
*C* Quick lime
*D* Soda ash -
correct answer ✅C
The prime importance of boiler fittings is:
*A* Economics
*B* To satisfy regulations
*C* Safety & efficiency
*D* Convenience -
correct answer ✅C
If a new boiler is not boiled out correctly, the result may be:
*A* Refractory damage
*B* Excessive waterside corrosion
*C* Excessively high water circulation rates
