NATE Oil Heating (Air) Installation
Technician Certification Exam
Questions And Correct Answers With
Rationales 2026
1. Which of the following is the primary purpose of an oil burner nozzle?
A. To mix air with fuel
B. To filter impurities from oil
C. To atomize fuel for combustion
D. To regulate oil pressure
Rationale: The nozzle atomizes the oil, creating a fine mist that burns
efficiently in the combustion chamber.
2. What is the typical maximum allowable stack temperature for an oil-
fired furnace?
A. 300°F
, B. 400°F
C. 500°F
D. 600°F
Rationale: Stack temperatures above 500°F indicate inefficient
combustion or a blocked vent.
3. The purpose of the cad cell in an oil burner is to:
A. Monitor oil pressure
B. Adjust combustion air
C. Control the fuel pump
D. Detect flame presence
Rationale: The cad cell is a flame sensor that ensures the burner
operates safely.
4. Which component controls the air-to-fuel ratio in an oil burner?
A. Transformer
B. Primary air shutter
C. Ignition transformer
D. Cad cell
Rationale: The primary air shutter adjusts airflow to ensure proper
combustion and efficiency.
5. What is the minimum clearances for an oil furnace to combustible
materials on the sides and top?
A. 0 inches side, 0 inches top
B. 1 inch side, 1 inch top
, C. 2 inches side, 2 inches top
D. 6 inches side, 12 inches top
Rationale: Manufacturers and NFPA standards require specific
clearances to prevent fire hazards.
6. What is the first step in performing a combustion analysis on an oil-
fired furnace?
A. Adjust the nozzle
B. Check and record stack temperature
C. Clean the combustion chamber
D. Replace the oil filter
Rationale: Measuring stack temperature establishes a baseline for
safe and efficient combustion.
7. Which type of oil filter is commonly installed on an oil-fired heating
system?
A. Inline cartridge filter
B. Spin-on cartridge filter
C. Mesh strainer
D. Bag filter
Rationale: Spin-on filters are standard in residential oil-fired systems
for ease of maintenance.
8. What is the typical operating pressure for an oil burner pump?
A. 20 psi
B. 40 psi
, C. 100 psi
D. 150 psi
Rationale: Residential oil burner pumps usually operate around 100
psi to ensure proper atomization.
9. What is the function of a primary control on an oil burner?
A. Measure oil viscosity
B. Control start, stop, and safety of the burner
C. Adjust air-fuel ratio
D. Clean the nozzle automatically
Rationale: The primary control ensures safe operation by regulating
ignition sequence and flame monitoring.
10. When adjusting an oil burner, what does a smoke test measure?
A. Oil pressure
B. Stack temperature
C. Combustion efficiency
D. Fuel flow rate
Rationale: Smoke tests indicate the completeness of combustion; less
smoke = more efficient burning.
11. A delayed ignition in an oil burner may be caused by:
A. High oil pressure
B. Clogged nozzle
C. Excess primary air
D. Low stack temperature
Technician Certification Exam
Questions And Correct Answers With
Rationales 2026
1. Which of the following is the primary purpose of an oil burner nozzle?
A. To mix air with fuel
B. To filter impurities from oil
C. To atomize fuel for combustion
D. To regulate oil pressure
Rationale: The nozzle atomizes the oil, creating a fine mist that burns
efficiently in the combustion chamber.
2. What is the typical maximum allowable stack temperature for an oil-
fired furnace?
A. 300°F
, B. 400°F
C. 500°F
D. 600°F
Rationale: Stack temperatures above 500°F indicate inefficient
combustion or a blocked vent.
3. The purpose of the cad cell in an oil burner is to:
A. Monitor oil pressure
B. Adjust combustion air
C. Control the fuel pump
D. Detect flame presence
Rationale: The cad cell is a flame sensor that ensures the burner
operates safely.
4. Which component controls the air-to-fuel ratio in an oil burner?
A. Transformer
B. Primary air shutter
C. Ignition transformer
D. Cad cell
Rationale: The primary air shutter adjusts airflow to ensure proper
combustion and efficiency.
5. What is the minimum clearances for an oil furnace to combustible
materials on the sides and top?
A. 0 inches side, 0 inches top
B. 1 inch side, 1 inch top
, C. 2 inches side, 2 inches top
D. 6 inches side, 12 inches top
Rationale: Manufacturers and NFPA standards require specific
clearances to prevent fire hazards.
6. What is the first step in performing a combustion analysis on an oil-
fired furnace?
A. Adjust the nozzle
B. Check and record stack temperature
C. Clean the combustion chamber
D. Replace the oil filter
Rationale: Measuring stack temperature establishes a baseline for
safe and efficient combustion.
7. Which type of oil filter is commonly installed on an oil-fired heating
system?
A. Inline cartridge filter
B. Spin-on cartridge filter
C. Mesh strainer
D. Bag filter
Rationale: Spin-on filters are standard in residential oil-fired systems
for ease of maintenance.
8. What is the typical operating pressure for an oil burner pump?
A. 20 psi
B. 40 psi
, C. 100 psi
D. 150 psi
Rationale: Residential oil burner pumps usually operate around 100
psi to ensure proper atomization.
9. What is the function of a primary control on an oil burner?
A. Measure oil viscosity
B. Control start, stop, and safety of the burner
C. Adjust air-fuel ratio
D. Clean the nozzle automatically
Rationale: The primary control ensures safe operation by regulating
ignition sequence and flame monitoring.
10. When adjusting an oil burner, what does a smoke test measure?
A. Oil pressure
B. Stack temperature
C. Combustion efficiency
D. Fuel flow rate
Rationale: Smoke tests indicate the completeness of combustion; less
smoke = more efficient burning.
11. A delayed ignition in an oil burner may be caused by:
A. High oil pressure
B. Clogged nozzle
C. Excess primary air
D. Low stack temperature
