Exam Practice Questions And Correct

Certified Oil Burner Technician Licensure Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• Which of the following is the primary function of an oil burner in a

heating system?

• Circulate air through the system
• Heat water for domestic use
• Ignite fuel oil to produce heat
• Reduce humidity in the environment

Rationale: The main function of an oil burner is to ignite fuel oil

efficiently to generate heat for the system.

• What is the optimal nozzle angle for a typical residential oil burner?

A. 30° 1 / 4

B. 45°

C. 60°

D. 90°

Rationale: A 60° nozzle angle ensures proper atomization and

combustion in residential burners.

• Which type of fuel oil is most commonly used in residential oil

burners?

• Diesel
• Kerosene
• No. 2 Fuel Oil
• No. 6 Fuel Oil

Rationale: No. 2 Fuel Oil is standard for residential heating due to its

efficiency and proper viscosity for burners.

• What component controls the air-to-fuel ratio in an oil burner?
• Pump
• Igniter
• Fan or air damper
• Nozzle

Rationale: The fan or air damper adjusts airflow, ensuring the correct

air-to-fuel mixture for efficient combustion.

• Which of the following is a sign of incomplete combustion in an oil

burner?

• Blue flame 2 / 4

• Soot formation
• Steady ignition
• High efficiency

Rationale: Soot formation indicates incomplete combustion, usually

due to poor atomization, improper air supply, or nozzle issues.

• The primary safety device that shuts off oil flow if the flame goes out is

called:

• Pressure switch
• Thermostat
• Cad cell or flame sensor
• Check valve

Rationale: The cad cell or flame sensor detects the presence of a flame

and shuts off oil supply if combustion fails.

• Which maintenance task is critical for preventing nozzle clogging?
• Adjusting thermostat
• Cleaning the air filter
• Replacing or cleaning the nozzle
• Lubricating the fan motor

Rationale: Regular nozzle cleaning or replacement ensures proper

atomization and efficient burner operation.

• What is the typical ignition system used in residential oil burners?
• Spark plug
• High-voltage transformer with electrodes 3 / 4

• Glow plug
• Pilot light

Rationale: A high-voltage transformer generates a spark at the

electrodes to ignite the fuel oil.

9. Excessive smoke from an oil burner typically indicates:

• Too much air
• Insufficient air or improper atomization
• Normal operation
• Clean fuel

Rationale: Thick, black smoke usually results from incomplete

combustion caused by poor atomization or restricted air supply.

• What is the function of a primary control in an oil burner?
• Pump oil to the nozzle
• Measure fuel pressure
• Start and stop the burner safely
• Filter debris from fuel

Rationale: The primary control ensures safe operation by starting the

burner and shutting it down in unsafe conditions.

• Which type of pump is commonly used in residential oil burners?
• Centrifugal pump
• Diaphragm pump
• Gear-type oil pump
• Piston pump
• / 4