ABSA: 4th Class Part B - Comprehensive Exam 1
questions with accurate answers
A ________ is a fired heater installed where the heat is needed, that
heats the air directly without the use of any ducting.
Select one:
a. Rooftop unit
b. Unit ventilator
c. Convector
d. Unit heater Ans✓✓✓ d
A boiler has an M-alkalinity that is greater than the prescribed control
range. What is the appropriate operator response?
Select one:
a. Reduce the frequency of bottom blowoff.
b. Lower the boiler water level.
c. Increase the rate of continuous blowdown.
d. Increase the rate of sodium hydroxide feed. Ans✓✓✓ c
A double-acting pump:
Select one:
a. Is a positive displacement pump
,b. Has two slide valves
c. Has two pistons on the driver end
d. Has two pistons on the pump end Ans✓✓✓ a
A flame rod:
Select one:
a. Develops a high resistance in the presence of a flame.
b. Forms an electric circuit with the rod, flame and burner
c. Is used only for oil fired burners
d. Is used in combination with a photocell Ans✓✓✓ b
A float operated low water fuel cutoff has its switch separated from
boiler pressure by:
Select one:
a. Packing
b. A seal cage
c. A bellows
d. A float cage Ans✓✓✓ c
A form of lubrication that requires continual motion of a shaft or surface
is:
Select one:
,a. Fluid film lubrication
b. Forced lubrication
c. Continuous lubrication
d. Boundary lubrication Ans✓✓✓ a
A gauge glass shows the level of a clear, colourless liquid as very dark,
is the ______________ gauge glass.
Select one:
a. Flat
b. Tubular
c. Reflex
d. Bi-colour Ans✓✓✓ c
A manual high-low switch should be switched to high or auto:
Select one:
a. Prior to ignition of the main flame
b. When pressure is too low
c. When the boiler has been properly warmed up
d. During boiler pre-purge Ans✓✓✓ c
, A photoelectric flame scanner:
Select one:
a. Produces a steady voltage signal
b. Requires a clear line of sight to the flame
c. conducts current through the flame
d. uses a pilot-stat Ans✓✓✓ b
A pressure relief device on a refrigeration system shall have sufficient
capacity to prevent the pressure in the pressure vessel from rising more
than _____ above the setting of the pressure relief device.
Select one:
a. 0.25
b. 103 kPa
c. 0.1
d. 1.5 Ans✓✓✓ c
A rotary pump:
Select one:
a. Is a dynamic pump
b. Should be equipped with a relief valve
c. Has severe discharge pulsations
questions with accurate answers
A ________ is a fired heater installed where the heat is needed, that
heats the air directly without the use of any ducting.
Select one:
a. Rooftop unit
b. Unit ventilator
c. Convector
d. Unit heater Ans✓✓✓ d
A boiler has an M-alkalinity that is greater than the prescribed control
range. What is the appropriate operator response?
Select one:
a. Reduce the frequency of bottom blowoff.
b. Lower the boiler water level.
c. Increase the rate of continuous blowdown.
d. Increase the rate of sodium hydroxide feed. Ans✓✓✓ c
A double-acting pump:
Select one:
a. Is a positive displacement pump
,b. Has two slide valves
c. Has two pistons on the driver end
d. Has two pistons on the pump end Ans✓✓✓ a
A flame rod:
Select one:
a. Develops a high resistance in the presence of a flame.
b. Forms an electric circuit with the rod, flame and burner
c. Is used only for oil fired burners
d. Is used in combination with a photocell Ans✓✓✓ b
A float operated low water fuel cutoff has its switch separated from
boiler pressure by:
Select one:
a. Packing
b. A seal cage
c. A bellows
d. A float cage Ans✓✓✓ c
A form of lubrication that requires continual motion of a shaft or surface
is:
Select one:
,a. Fluid film lubrication
b. Forced lubrication
c. Continuous lubrication
d. Boundary lubrication Ans✓✓✓ a
A gauge glass shows the level of a clear, colourless liquid as very dark,
is the ______________ gauge glass.
Select one:
a. Flat
b. Tubular
c. Reflex
d. Bi-colour Ans✓✓✓ c
A manual high-low switch should be switched to high or auto:
Select one:
a. Prior to ignition of the main flame
b. When pressure is too low
c. When the boiler has been properly warmed up
d. During boiler pre-purge Ans✓✓✓ c
, A photoelectric flame scanner:
Select one:
a. Produces a steady voltage signal
b. Requires a clear line of sight to the flame
c. conducts current through the flame
d. uses a pilot-stat Ans✓✓✓ b
A pressure relief device on a refrigeration system shall have sufficient
capacity to prevent the pressure in the pressure vessel from rising more
than _____ above the setting of the pressure relief device.
Select one:
a. 0.25
b. 103 kPa
c. 0.1
d. 1.5 Ans✓✓✓ c
A rotary pump:
Select one:
a. Is a dynamic pump
b. Should be equipped with a relief valve
c. Has severe discharge pulsations
