ABSA 4th Class Part B Comprehensive Exam 1 –
Complete Study Guide, Practice Questions &
Verified Answers 2026
Temporary hardness in feedwater is caused by:
Select one:
a. Magnesium sulphate
b. Calcium carbonate
c. Magnesium bicarbonate
d. Sodium nitrate - correct answers -c
What is the recommended boiler water pH for wet layup?
Select one:
a. 10
b. 12
c. 7.5
d. 7 - correct answers -a
A photoelectric flame scanner:
Select one:
1
,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 - correct answers -b
Heavy oil recovered using SAGD or CSS is properly referred to as
Select one:
a. bottoms
b. crude
c. tar
d. bitumen - correct answers -d
Humidifying units that force warm air through a wet pad, and return the air to the room, are called:
Select one:
a. Wetted element humidifiers
b. Pan type humidifiers with plates
c. Atomizing humidifiers
d. Bypass type humidifiers - correct answers -a
The kind of grease used for heavily loaded machinery operating at slow speeds is the:
Select one:
2
,a. Sodium base grease
b. Specialty grease
c. Calcium base grease
d. Aluminum base grease - correct answers -b
One of the advantages of gas-fired infrared heating over other types of heating systems is:
Select one:
a. Gas-fired infrared heaters can be used as the main heating source for a large building
b. Gas-fired infrared heaters can provide effective spot heating
c. Gas-fired infrared heaters require no fuel handling equipment
d. Gas-fired infrared heaters can heat large volume enclosures with little fuel - correct answers -b
The normal loss of zeolite in a sodium zeolite softener is about _______ per year.
Select one:
a. 0.1
b. 0.15
c. 0.03
d. 0.05 - correct answers -c
A form of lubrication that requires continual motion of a shaft or surface is:
3
, Select one:
a. Fluid film lubrication
b. Forced lubrication
c. Continuous lubrication
d. Boundary lubrication - correct answers -a
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 - correct answers -d
With antifriction bearings using grease, the bearings:
Select one:
a. Never require cleaning
b. Are cleaned less often than oil-lubricated bearings
c. can be cleaned by adding solvent to the grease cartridge
d. Must be cleaned twice as often as oil-lubricated bearings - correct answers -b
4
Complete Study Guide, Practice Questions &
Verified Answers 2026
Temporary hardness in feedwater is caused by:
Select one:
a. Magnesium sulphate
b. Calcium carbonate
c. Magnesium bicarbonate
d. Sodium nitrate - correct answers -c
What is the recommended boiler water pH for wet layup?
Select one:
a. 10
b. 12
c. 7.5
d. 7 - correct answers -a
A photoelectric flame scanner:
Select one:
1
,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 - correct answers -b
Heavy oil recovered using SAGD or CSS is properly referred to as
Select one:
a. bottoms
b. crude
c. tar
d. bitumen - correct answers -d
Humidifying units that force warm air through a wet pad, and return the air to the room, are called:
Select one:
a. Wetted element humidifiers
b. Pan type humidifiers with plates
c. Atomizing humidifiers
d. Bypass type humidifiers - correct answers -a
The kind of grease used for heavily loaded machinery operating at slow speeds is the:
Select one:
2
,a. Sodium base grease
b. Specialty grease
c. Calcium base grease
d. Aluminum base grease - correct answers -b
One of the advantages of gas-fired infrared heating over other types of heating systems is:
Select one:
a. Gas-fired infrared heaters can be used as the main heating source for a large building
b. Gas-fired infrared heaters can provide effective spot heating
c. Gas-fired infrared heaters require no fuel handling equipment
d. Gas-fired infrared heaters can heat large volume enclosures with little fuel - correct answers -b
The normal loss of zeolite in a sodium zeolite softener is about _______ per year.
Select one:
a. 0.1
b. 0.15
c. 0.03
d. 0.05 - correct answers -c
A form of lubrication that requires continual motion of a shaft or surface is:
3
, Select one:
a. Fluid film lubrication
b. Forced lubrication
c. Continuous lubrication
d. Boundary lubrication - correct answers -a
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 - correct answers -d
With antifriction bearings using grease, the bearings:
Select one:
a. Never require cleaning
b. Are cleaned less often than oil-lubricated bearings
c. can be cleaned by adding solvent to the grease cartridge
d. Must be cleaned twice as often as oil-lubricated bearings - correct answers -b
4
