ABSA 5th Class Exam Questions and
Answers36
During the regeneration of a sodium zeolite softener, what happens to the elemental impuritites
that are attached to the zeolite? - ANSWERS -They are exchanged for sodium
Conditions which can occur within the boiler are ___________ - ANSWERS -scale, corrosion,
sludge, foaming
During the backwash cycle the zeolite gets smaller due to the churning action and find their way
to the sewer, this process is called: - ANSWERS -attrition
Regarding a sodium zeolite softener, what is the term used to describe the following modes of
operation when they are considered together?
Backwash, injection, exchange, rinse. - ANSWERS -Regeneration
Where are the return openings located regarding air distribution systems? - ANSWERS -Return
air openings are located on inner walls.
The minimum temperature of the water used in a hydrostatic test of a boiler cannot be less than
what temperature? - ANSWERS -20 degrees Celsius
Which of the following are causes of pressure explosions?
1. effects of corrosion
,2. weak pilot flame
3. stressed material due to heating too quickly
4. insufficient purge
5. scale and sludge build-up - ANSWERS -1, 3, 5
Carbon, which is not combined with hydrogen, is referred to as: - ANSWERS -Fixed Carbon
Maximum static pressure in a fuel oil line is approximately: - ANSWERS -35 kPa
Combustion of a fuel in a boiler furnace: - ANSWERS -should be performed with a minimum of
excess air
What is a hydrostatic test? - ANSWERS -A way in which pressure vessels can be tested for
strength and leaks.
How often do burner and fan motors which uses standard bearing normally require lubrication?
- ANSWERS -Yearly
On a hot water boiler, the pressure differential between the operating pressure and the safety
relief valve set pressure must be (at a minimum):
1. 25% of operating pressure
,2. 125% of operating pressure
3. 69 kPa
4. 25% of the safety relief valve set pressure - ANSWERS -3, 4
In hot water boiler operation the maximum operating temperature should never exceed: -
ANSWERS -121 degrees celsius
A substance, which will absorb humidity inside a boiler during dry lay up is: - ANSWERS -
Activated alumina
When draft is produced by natural means: - ANSWERS -cooler air surrounding the boiler
increases draft
Coal is composed of the following combustible components: - ANSWERS -Carbon, hydrogen,
Sulphur
Which of the following are causes of furnace explosions?
1. main fuel valve closed when the burner flame is lost
2. insufficient purge
3. burners lit from hot refractory
, 4. effects of corrosion
5. admission of fuel before ignition source - ANSWERS -3,4,5
Which grade of oil is the most popular for domestic and small commercial boilers? - ANSWERS -
Grade 2
The inclined manometer as compared to the U manometer is what? - ANSWERS -More accurate.
How can the draft through a natural draft furnace be increased? - ANSWERS -Increase the
temperature of the stack
The main function of a gas burner is: - ANSWERS -provision of O2 - fuel contact
The minimum distance from furnace to oil storage tank is: - ANSWERS -2 feet
One of the main component of an electric ignition system is the step-up transformer which
takes 120 V and boosts it to _____ volts - ANSWERS -10,000 - 12,000 volts.
Combustion of a fuel in a boiler furnace should be performed in what conditions? - ANSWERS -
There should be a minimum of excess air.
What type of oil burner is used when oil is supplied under high pressure? - ANSWERS -
Mechanical Atomizing Burner
An air atomizing compressor is usually what type? - ANSWERS -A rotary type.
Which of the following advantages does oil have over coal as a boiler fuel?
Answers36
During the regeneration of a sodium zeolite softener, what happens to the elemental impuritites
that are attached to the zeolite? - ANSWERS -They are exchanged for sodium
Conditions which can occur within the boiler are ___________ - ANSWERS -scale, corrosion,
sludge, foaming
During the backwash cycle the zeolite gets smaller due to the churning action and find their way
to the sewer, this process is called: - ANSWERS -attrition
Regarding a sodium zeolite softener, what is the term used to describe the following modes of
operation when they are considered together?
Backwash, injection, exchange, rinse. - ANSWERS -Regeneration
Where are the return openings located regarding air distribution systems? - ANSWERS -Return
air openings are located on inner walls.
The minimum temperature of the water used in a hydrostatic test of a boiler cannot be less than
what temperature? - ANSWERS -20 degrees Celsius
Which of the following are causes of pressure explosions?
1. effects of corrosion
,2. weak pilot flame
3. stressed material due to heating too quickly
4. insufficient purge
5. scale and sludge build-up - ANSWERS -1, 3, 5
Carbon, which is not combined with hydrogen, is referred to as: - ANSWERS -Fixed Carbon
Maximum static pressure in a fuel oil line is approximately: - ANSWERS -35 kPa
Combustion of a fuel in a boiler furnace: - ANSWERS -should be performed with a minimum of
excess air
What is a hydrostatic test? - ANSWERS -A way in which pressure vessels can be tested for
strength and leaks.
How often do burner and fan motors which uses standard bearing normally require lubrication?
- ANSWERS -Yearly
On a hot water boiler, the pressure differential between the operating pressure and the safety
relief valve set pressure must be (at a minimum):
1. 25% of operating pressure
,2. 125% of operating pressure
3. 69 kPa
4. 25% of the safety relief valve set pressure - ANSWERS -3, 4
In hot water boiler operation the maximum operating temperature should never exceed: -
ANSWERS -121 degrees celsius
A substance, which will absorb humidity inside a boiler during dry lay up is: - ANSWERS -
Activated alumina
When draft is produced by natural means: - ANSWERS -cooler air surrounding the boiler
increases draft
Coal is composed of the following combustible components: - ANSWERS -Carbon, hydrogen,
Sulphur
Which of the following are causes of furnace explosions?
1. main fuel valve closed when the burner flame is lost
2. insufficient purge
3. burners lit from hot refractory
, 4. effects of corrosion
5. admission of fuel before ignition source - ANSWERS -3,4,5
Which grade of oil is the most popular for domestic and small commercial boilers? - ANSWERS -
Grade 2
The inclined manometer as compared to the U manometer is what? - ANSWERS -More accurate.
How can the draft through a natural draft furnace be increased? - ANSWERS -Increase the
temperature of the stack
The main function of a gas burner is: - ANSWERS -provision of O2 - fuel contact
The minimum distance from furnace to oil storage tank is: - ANSWERS -2 feet
One of the main component of an electric ignition system is the step-up transformer which
takes 120 V and boosts it to _____ volts - ANSWERS -10,000 - 12,000 volts.
Combustion of a fuel in a boiler furnace should be performed in what conditions? - ANSWERS -
There should be a minimum of excess air.
What type of oil burner is used when oil is supplied under high pressure? - ANSWERS -
Mechanical Atomizing Burner
An air atomizing compressor is usually what type? - ANSWERS -A rotary type.
Which of the following advantages does oil have over coal as a boiler fuel?
