OIL BURNER LICENSE EXAM WITH 300+ PRACTICE QUESTIONS & DETAILED RATIONALES

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OIL BURNER LICENSE EXAM AND PRACTICE

EXAM NEWEST ACTUAL EXAM COMPLETE

70 QUESTIONS AND CORRECT ANSWERS

(VERIFIED ANSWERS) ||COMPLETE A+

GUIDE




1. The ideal air-to-fuel ratio for complete combustion of No. 2

fuel oil by weight is approximately:

A) 5:1

B) 10:1

C) 15:1

D) 20:1

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Answer: C

Rationale: Complete combustion of No. 2 oil requires about

14.5–15 lbs of air per lb of fuel.

2. Which gas indicates incomplete combustion in an oil burner

flue?

A) O₂

B) CO₂

C) CO

D) N₂

Answer: C

Rationale: CO forms when oxygen is insufficient. It is toxic and

indicates inefficiency.

3. Scenario: You measure 12% CO₂ and 50 ppm CO in the

stack. What should you do first?

A) Increase combustion air

B) Decrease combustion air

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C) Increase fuel pressure

D) Replace the nozzle

Answer: A

Rationale: CO indicates incomplete combustion. Increase air to

lower CO.

4. The three elements required for combustion are:

A) Fuel, oxygen, spark

B) Fuel, heat, oxygen

C) Fuel, nitrogen, heat

D) Oxygen, heat, carbon

Answer: B

Rationale: Fire triangle = fuel, oxygen, heat.

5. Excess air in an oil burner typically ranges between:

A) 0–10%

B) 15–50%

C) 60–80%

D) 100–150%

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Answer: B

Rationale: 15–50% excess air ensures complete combustion

without excessive heat loss.

6. What is the primary purpose of draft over the fire?

A) Cool the combustion chamber

B) Remove combustion gases and supply air

C) Increase flame temperature

D) Reduce fuel consumption

Answer: B

Rationale: Draft removes products of combustion and supplies

fresh air.

7. Which of the following will cause a puffback?

A) High draft

B) Delayed ignition

C) Low stack temperature

D) High CO₂