CT Oil Heating Contractor Exam
Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. What is the primary purpose of a draft regulator in an oil-fired
heating system?
A. To increase burner fuel pressure
B. To regulate the temperature of the supply air
C. To maintain a relatively constant draft through the appliance
D. To increase combustion air
Rationale: A draft regulator, or barometric damper, admits room air
into the flue when necessary to stabilize chimney draft. Proper draft
helps maintain consistent combustion and prevents excessive negative
pressure from affecting burner operation.
2. What is the primary function of the oil burner nozzle?
,A. To ignite the fuel
B. To atomize oil into a fine spray for combustion
C. To regulate chimney draft
D. To filter combustion air
Rationale: The nozzle converts pressurized heating oil into a finely
atomized spray. Proper atomization is essential because small fuel
droplets mix more effectively with combustion air and burn efficiently.
3. Which component is responsible for initiating the spark that
ignites the oil-air mixture?
A. Cad cell
B. Oil pump
C. Ignition transformer
D. Primary control
Rationale: The ignition transformer supplies the high voltage needed
to create an electrical arc across the electrodes. This spark ignites the
atomized fuel when the burner begins its firing sequence.
4. What is the purpose of a cad cell in an oil burner?
A. To measure oil pressure
B. To regulate combustion air
,C. To control the oil pump pressure
D. To sense the presence of flame
Rationale: A cadmium sulfide flame sensor, commonly called a cad
cell, detects light produced by the burner flame. The primary control
uses this signal to determine whether safe ignition has occurred.
5. What is the most likely result of an excessively dirty oil burner
nozzle?
A. Increased fuel efficiency
B. Increased chimney draft
C. Poor atomization and improper combustion
D. Increased thermostat accuracy
Rationale: Dirt or deposits on the nozzle can distort the spray pattern
or reduce fuel flow. This can produce ignition problems, smoke, soot,
and inefficient combustion.
6. What is the purpose of the oil filter installed in the fuel supply
system?
A. To increase oil temperature
B. To remove contaminants from the fuel before it reaches the burner
C. To increase pump pressure
D. To control chimney draft
, Rationale: Oil filters remove dirt, rust, sludge, and other contaminants
that could damage the fuel pump or plug the nozzle. Clean fuel is
necessary for reliable burner operation.
7. A burner that produces excessive black smoke is most commonly
experiencing which condition?
A. Excess combustion air
B. Excessive chimney draft only
C. Insufficient combustion air or poor fuel atomization
D. Excessive thermostat voltage
Rationale: Black smoke generally indicates incomplete combustion
and excessive soot formation. Common causes include inadequate
combustion air, a dirty nozzle, poor spray pattern, incorrect pump
pressure, or restricted air passages.
8. What is the purpose of a primary control on an oil burner?
A. To regulate building water pressure
B. To control the chimney
C. To regulate room humidity
D. To sequence burner operation and provide safety shutdown
Rationale: The primary control manages the burner operating
sequence, including motor, ignition, fuel valve, and flame detection. If
Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. What is the primary purpose of a draft regulator in an oil-fired
heating system?
A. To increase burner fuel pressure
B. To regulate the temperature of the supply air
C. To maintain a relatively constant draft through the appliance
D. To increase combustion air
Rationale: A draft regulator, or barometric damper, admits room air
into the flue when necessary to stabilize chimney draft. Proper draft
helps maintain consistent combustion and prevents excessive negative
pressure from affecting burner operation.
2. What is the primary function of the oil burner nozzle?
,A. To ignite the fuel
B. To atomize oil into a fine spray for combustion
C. To regulate chimney draft
D. To filter combustion air
Rationale: The nozzle converts pressurized heating oil into a finely
atomized spray. Proper atomization is essential because small fuel
droplets mix more effectively with combustion air and burn efficiently.
3. Which component is responsible for initiating the spark that
ignites the oil-air mixture?
A. Cad cell
B. Oil pump
C. Ignition transformer
D. Primary control
Rationale: The ignition transformer supplies the high voltage needed
to create an electrical arc across the electrodes. This spark ignites the
atomized fuel when the burner begins its firing sequence.
4. What is the purpose of a cad cell in an oil burner?
A. To measure oil pressure
B. To regulate combustion air
,C. To control the oil pump pressure
D. To sense the presence of flame
Rationale: A cadmium sulfide flame sensor, commonly called a cad
cell, detects light produced by the burner flame. The primary control
uses this signal to determine whether safe ignition has occurred.
5. What is the most likely result of an excessively dirty oil burner
nozzle?
A. Increased fuel efficiency
B. Increased chimney draft
C. Poor atomization and improper combustion
D. Increased thermostat accuracy
Rationale: Dirt or deposits on the nozzle can distort the spray pattern
or reduce fuel flow. This can produce ignition problems, smoke, soot,
and inefficient combustion.
6. What is the purpose of the oil filter installed in the fuel supply
system?
A. To increase oil temperature
B. To remove contaminants from the fuel before it reaches the burner
C. To increase pump pressure
D. To control chimney draft
, Rationale: Oil filters remove dirt, rust, sludge, and other contaminants
that could damage the fuel pump or plug the nozzle. Clean fuel is
necessary for reliable burner operation.
7. A burner that produces excessive black smoke is most commonly
experiencing which condition?
A. Excess combustion air
B. Excessive chimney draft only
C. Insufficient combustion air or poor fuel atomization
D. Excessive thermostat voltage
Rationale: Black smoke generally indicates incomplete combustion
and excessive soot formation. Common causes include inadequate
combustion air, a dirty nozzle, poor spray pattern, incorrect pump
pressure, or restricted air passages.
8. What is the purpose of a primary control on an oil burner?
A. To regulate building water pressure
B. To control the chimney
C. To regulate room humidity
D. To sequence burner operation and provide safety shutdown
Rationale: The primary control manages the burner operating
sequence, including motor, ignition, fuel valve, and flame detection. If
