ABSA 5TH CLASS EXAM GUARANTEED QUESTIONS WITH VERIFIED ANSWERS
100 % PASS 2026-2027
1. Where are the return openings located regarding air distribution systems?: -
Return air openings are located on inner walls.
2. The minimum temperature of the water used in a hydrostatic test of a boiler
cannot be less than what temperature?: 20 degrees Celsius
3. 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: 1, 3, 5
4. Carbon, which is not combined with hydrogen, is referred to as:: Fixed Carbon
5. Maximum static pressure in a fuel oil line is approximately:: 35 kPa
6. Combustion of a fuel in a boiler furnace:: should be performed with a minimum of excess air
7. What is a hydrostatic test?: A way in which pressure vessels can be tested for strength and leaks.
8. How often do burner and fan motors which uses standard bearing normally
require lubrication?: Yearly
9. On a hot water boiler, the pressure differential between the operating pres-
sure 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: 3, 4
,ABSA 5TH CLASS EXAM GUARANTEED QUESTIONS WITH VERIFIED ANSWERS
100 % PASS 2026-2027
10. In hot water boiler operation the maximum operating temperature should
never exceed:: 121 degrees celsius
11. A substance, which will absorb humidity inside a boiler during dry lay up
is:: Activated alumina
12. When draft is produced by natural means:: cooler air surrounding the boiler increases draft
13. Coal is composed of the following combustible components:: Carbon, hydrogen,
Sulphur
14. 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: 3,4,5
15. Which grade of oil is the most popular for domestic and small commercial
boilers?: Grade 2
16. The inclined manometer as compared to the U manometer is what?: More
accurate.
17. How can the draft through a natural draft furnace be increased?: Increase the
temperature of the stack
18. The main function of a gas burner is:: provision of O2 - fuel contact
19. The minimum distance from furnace to oil storage tank is:: 2 feet
20. One of the main component of an electric ignition system is the step-up
transformer which takes 120 V and boosts it to volts: 10,000 - 12,000 volts.
21. Combustion of a fuel in a boiler furnace should be performed in what
conditions?: There should be a minimum of excess air.
22. What type of oil burner is used when oil is supplied under high pressure?: -
Mechanical Atomizing Burner
23. An air atomizing compressor is usually what type?: A rotary type.
,ABSA 5TH CLASS EXAM GUARANTEED QUESTIONS WITH VERIFIED ANSWERS
100 % PASS 2026-2027
24. Which of the following advantages does oil have over coal as a boiler fuel?
1. requires less storage space
2. costs less to handle
3. fuel quantity is easier to control
4. burns more cleanly: All of the above
25. In a boiler burner with 3 fixed capacity nozzles,the intermediate and high
burner nozzles have higher capacities than the primary burner nozzle for what
reason?: To allow better boiler warm-ups
26. What is a manometer used for?: Measure draft
27. A draft gauge on a furnace indicates the draft in:: mm of water column
28. A solenoid type fuel gas valve is held close by what?: Fuel pressure
29. Regarding a burner with 3 fixed capacity nozzles,the secondary and tertiary
nozzles are ignited by:: Primary burner
30. Ethane is a component of natural gas and constitutes a percent volume
of:: 10-20%
31. An interrupted pilot does what?: Lights, completes a trial, and extinguishes after the main flame is
established.
32. A very popular packaged boiler gas burner is the:: Ring burner
33. An intermittent pilot does what?: Lights the main flame and remains on with it.
34. Before atomization can occur, heavy oils are heated to approximately
degrees C.: 95
35. A fuel storage tank must be located a minimum of away from the
furnace: 2 feet
36. A refractory burner disadvantage is:: High initial cost
37. Maximum static pressure in a fuel oil line is approximately what?: 35 KPA
38. When a gas fired burner is burning fuel properly
a) it will have a blue flame with short yellow tips
b) the furnace will pulsate
c) there will be no turbulence
100 % PASS 2026-2027
1. Where are the return openings located regarding air distribution systems?: -
Return air openings are located on inner walls.
2. The minimum temperature of the water used in a hydrostatic test of a boiler
cannot be less than what temperature?: 20 degrees Celsius
3. 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: 1, 3, 5
4. Carbon, which is not combined with hydrogen, is referred to as:: Fixed Carbon
5. Maximum static pressure in a fuel oil line is approximately:: 35 kPa
6. Combustion of a fuel in a boiler furnace:: should be performed with a minimum of excess air
7. What is a hydrostatic test?: A way in which pressure vessels can be tested for strength and leaks.
8. How often do burner and fan motors which uses standard bearing normally
require lubrication?: Yearly
9. On a hot water boiler, the pressure differential between the operating pres-
sure 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: 3, 4
,ABSA 5TH CLASS EXAM GUARANTEED QUESTIONS WITH VERIFIED ANSWERS
100 % PASS 2026-2027
10. In hot water boiler operation the maximum operating temperature should
never exceed:: 121 degrees celsius
11. A substance, which will absorb humidity inside a boiler during dry lay up
is:: Activated alumina
12. When draft is produced by natural means:: cooler air surrounding the boiler increases draft
13. Coal is composed of the following combustible components:: Carbon, hydrogen,
Sulphur
14. 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: 3,4,5
15. Which grade of oil is the most popular for domestic and small commercial
boilers?: Grade 2
16. The inclined manometer as compared to the U manometer is what?: More
accurate.
17. How can the draft through a natural draft furnace be increased?: Increase the
temperature of the stack
18. The main function of a gas burner is:: provision of O2 - fuel contact
19. The minimum distance from furnace to oil storage tank is:: 2 feet
20. One of the main component of an electric ignition system is the step-up
transformer which takes 120 V and boosts it to volts: 10,000 - 12,000 volts.
21. Combustion of a fuel in a boiler furnace should be performed in what
conditions?: There should be a minimum of excess air.
22. What type of oil burner is used when oil is supplied under high pressure?: -
Mechanical Atomizing Burner
23. An air atomizing compressor is usually what type?: A rotary type.
,ABSA 5TH CLASS EXAM GUARANTEED QUESTIONS WITH VERIFIED ANSWERS
100 % PASS 2026-2027
24. Which of the following advantages does oil have over coal as a boiler fuel?
1. requires less storage space
2. costs less to handle
3. fuel quantity is easier to control
4. burns more cleanly: All of the above
25. In a boiler burner with 3 fixed capacity nozzles,the intermediate and high
burner nozzles have higher capacities than the primary burner nozzle for what
reason?: To allow better boiler warm-ups
26. What is a manometer used for?: Measure draft
27. A draft gauge on a furnace indicates the draft in:: mm of water column
28. A solenoid type fuel gas valve is held close by what?: Fuel pressure
29. Regarding a burner with 3 fixed capacity nozzles,the secondary and tertiary
nozzles are ignited by:: Primary burner
30. Ethane is a component of natural gas and constitutes a percent volume
of:: 10-20%
31. An interrupted pilot does what?: Lights, completes a trial, and extinguishes after the main flame is
established.
32. A very popular packaged boiler gas burner is the:: Ring burner
33. An intermittent pilot does what?: Lights the main flame and remains on with it.
34. Before atomization can occur, heavy oils are heated to approximately
degrees C.: 95
35. A fuel storage tank must be located a minimum of away from the
furnace: 2 feet
36. A refractory burner disadvantage is:: High initial cost
37. Maximum static pressure in a fuel oil line is approximately what?: 35 KPA
38. When a gas fired burner is burning fuel properly
a) it will have a blue flame with short yellow tips
b) the furnace will pulsate
c) there will be no turbulence
