Compressor Technician Practice Exam
Questions With Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
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1. What is the primary function of a compressor in industrial systems?
A. To convert electrical energy into heat
B. To increase the pressure of a gas
C. To decrease fluid viscosity
D. To filter air contaminants
Answer: B. To increase the pressure of a gas
Rationale: A compressor works by reducing gas volume and increasing
its pressure for use in industrial applications.
2. Which type of compressor uses pistons to compress air?
A. Centrifugal compressor
B. Rotary screw compressor
C. Reciprocating compressor
D. Axial compressor
Answer: C. Reciprocating compressor
Rationale: Reciprocating compressors use pistons driven by a crankshaft
to compress air.
,3. What is the main cause of overheating in compressors?
A. Low suction pressure
B. Excessive lubrication
C. Restricted airflow or cooling failure
D. High voltage supply
Answer: C. Restricted airflow or cooling failure
Rationale: Poor cooling or blocked airflow causes heat buildup in
compressor systems.
4. Which component removes moisture from compressed air?
A. Receiver tank
B. Air dryer
C. Pressure gauge
D. Relief valve
Answer: B. Air dryer
Rationale: Air dryers eliminate moisture to prevent corrosion and system
damage.
5. What is the function of a compressor unloader valve?
A. Increases air pressure
B. Releases excess refrigerant
C. Reduces load during startup
D. Filters oil from air
Answer: C. Reduces load during startup
Rationale: Unloader valves reduce starting torque by relieving pressure
during startup.
,6. Which lubricant is commonly used in air compressors?
A. Hydraulic oil
B. Motor oil
C. Compressor oil
D. Gear grease
Answer: C. Compressor oil
Rationale: Compressor oil is specially formulated for high-temperature
and pressure conditions.
7. What happens when compressor intake air is restricted?
A. Pressure increases excessively
B. Efficiency decreases
C. Oil consumption stops
D. Voltage increases
Answer: B. Efficiency decreases
Rationale: Restricted intake reduces airflow and system efficiency.
8. What is the purpose of a pressure relief valve?
A. Increase airflow
B. Maintain lubrication
C. Prevent overpressure
D. Control temperature
Answer: C. Prevent overpressure
Rationale: Relief valves protect equipment from dangerous pressure
buildup.
, 9. Which compressor type is most efficient for continuous large-scale
operation?
A. Reciprocating
B. Centrifugal
C. Diaphragm
D. Scroll
Answer: B. Centrifugal
Rationale: Centrifugal compressors are ideal for high-volume continuous
flow applications.
10. What is cavitation in compressors?
A. Electrical failure
B. Formation of vapor bubbles
C. Oil leakage
D. Overheating coils
Answer: B. Formation of vapor bubbles
Rationale: Cavitation occurs when vapor bubbles form and collapse,
damaging components.
11. What is the purpose of a compressor intercooler?
A. Increase air temperature
B. Cool air between compression stages
C. Filter oil
D. Increase voltage
Answer: B. Cool air between compression stages
Rationale: Intercoolers reduce air temperature to improve efficiency.
Questions With Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. What is the primary function of a compressor in industrial systems?
A. To convert electrical energy into heat
B. To increase the pressure of a gas
C. To decrease fluid viscosity
D. To filter air contaminants
Answer: B. To increase the pressure of a gas
Rationale: A compressor works by reducing gas volume and increasing
its pressure for use in industrial applications.
2. Which type of compressor uses pistons to compress air?
A. Centrifugal compressor
B. Rotary screw compressor
C. Reciprocating compressor
D. Axial compressor
Answer: C. Reciprocating compressor
Rationale: Reciprocating compressors use pistons driven by a crankshaft
to compress air.
,3. What is the main cause of overheating in compressors?
A. Low suction pressure
B. Excessive lubrication
C. Restricted airflow or cooling failure
D. High voltage supply
Answer: C. Restricted airflow or cooling failure
Rationale: Poor cooling or blocked airflow causes heat buildup in
compressor systems.
4. Which component removes moisture from compressed air?
A. Receiver tank
B. Air dryer
C. Pressure gauge
D. Relief valve
Answer: B. Air dryer
Rationale: Air dryers eliminate moisture to prevent corrosion and system
damage.
5. What is the function of a compressor unloader valve?
A. Increases air pressure
B. Releases excess refrigerant
C. Reduces load during startup
D. Filters oil from air
Answer: C. Reduces load during startup
Rationale: Unloader valves reduce starting torque by relieving pressure
during startup.
,6. Which lubricant is commonly used in air compressors?
A. Hydraulic oil
B. Motor oil
C. Compressor oil
D. Gear grease
Answer: C. Compressor oil
Rationale: Compressor oil is specially formulated for high-temperature
and pressure conditions.
7. What happens when compressor intake air is restricted?
A. Pressure increases excessively
B. Efficiency decreases
C. Oil consumption stops
D. Voltage increases
Answer: B. Efficiency decreases
Rationale: Restricted intake reduces airflow and system efficiency.
8. What is the purpose of a pressure relief valve?
A. Increase airflow
B. Maintain lubrication
C. Prevent overpressure
D. Control temperature
Answer: C. Prevent overpressure
Rationale: Relief valves protect equipment from dangerous pressure
buildup.
, 9. Which compressor type is most efficient for continuous large-scale
operation?
A. Reciprocating
B. Centrifugal
C. Diaphragm
D. Scroll
Answer: B. Centrifugal
Rationale: Centrifugal compressors are ideal for high-volume continuous
flow applications.
10. What is cavitation in compressors?
A. Electrical failure
B. Formation of vapor bubbles
C. Oil leakage
D. Overheating coils
Answer: B. Formation of vapor bubbles
Rationale: Cavitation occurs when vapor bubbles form and collapse,
damaging components.
11. What is the purpose of a compressor intercooler?
A. Increase air temperature
B. Cool air between compression stages
C. Filter oil
D. Increase voltage
Answer: B. Cool air between compression stages
Rationale: Intercoolers reduce air temperature to improve efficiency.
