Certificate Of Qualification Refrigeration And
Air Conditioning Systems Mechanic (313A)
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A | Instant
Download Pdf
1. What is the primary function of a compressor in a refrigeration
system?
A. Absorb heat from the evaporator
B. Reject heat to the atmosphere
C. Increase refrigerant pressure and temperature
D. Store liquid refrigerant
Rationale: The compressor raises refrigerant pressure and
temperature so heat can be rejected in the condenser.
2. Which component meters refrigerant flow into the evaporator?
A. Condenser
B. Receiver
C. Expansion device
D. Oil separator
Rationale: Expansion devices regulate refrigerant flow and reduce
pressure entering the evaporator.
3. Which refrigerant property allows heat absorption during
evaporation?
A. Density
, B. Viscosity
C. Latent heat
D. Specific gravity
Rationale: Latent heat enables refrigerant to absorb large
amounts of heat during phase change.
4. Superheat is measured at which location?
A. Condenser outlet
B. Compressor discharge
C. Evaporator outlet
D. Receiver inlet
Rationale: Superheat ensures only vapor enters the compressor.
5. Subcooling occurs in which component?
A. Evaporator
B. Compressor
C. Condenser
D. Expansion valve
Rationale: Subcooling removes heat from liquid refrigerant below
saturation temperature.
6. Which device prevents liquid refrigerant from entering the
compressor?
A. Filter drier
B. Accumulator
C. Receiver
D. Sight glass
Rationale: Accumulators trap liquid refrigerant in suction lines.
7. What type of compressor is commonly used in residential AC
systems?
, A. Centrifugal
B. Screw
C. Scroll
D. Rotary vane
Rationale: Scroll compressors are efficient and reliable for
residential systems.
8. Which pressure is measured on the low side of a system?
A. Head pressure
B. Discharge pressure
C. Suction pressure
D. Static pressure
Rationale: Suction pressure represents evaporator pressure.
9. What happens when a system is undercharged?
A. High suction pressure
B. High head pressure
C. Low suction pressure
D. Flooded evaporator
Rationale: Insufficient refrigerant reduces evaporator pressure.
10. What is the purpose of a filter drier?
A. Increase oil return
B. Store refrigerant
C. Remove moisture and contaminants
D. Reduce pressure
Rationale: Moisture and debris can damage system components.
11. Which refrigerant is classified as an HFC?
A. R-22
B. R-12
Air Conditioning Systems Mechanic (313A)
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A | Instant
Download Pdf
1. What is the primary function of a compressor in a refrigeration
system?
A. Absorb heat from the evaporator
B. Reject heat to the atmosphere
C. Increase refrigerant pressure and temperature
D. Store liquid refrigerant
Rationale: The compressor raises refrigerant pressure and
temperature so heat can be rejected in the condenser.
2. Which component meters refrigerant flow into the evaporator?
A. Condenser
B. Receiver
C. Expansion device
D. Oil separator
Rationale: Expansion devices regulate refrigerant flow and reduce
pressure entering the evaporator.
3. Which refrigerant property allows heat absorption during
evaporation?
A. Density
, B. Viscosity
C. Latent heat
D. Specific gravity
Rationale: Latent heat enables refrigerant to absorb large
amounts of heat during phase change.
4. Superheat is measured at which location?
A. Condenser outlet
B. Compressor discharge
C. Evaporator outlet
D. Receiver inlet
Rationale: Superheat ensures only vapor enters the compressor.
5. Subcooling occurs in which component?
A. Evaporator
B. Compressor
C. Condenser
D. Expansion valve
Rationale: Subcooling removes heat from liquid refrigerant below
saturation temperature.
6. Which device prevents liquid refrigerant from entering the
compressor?
A. Filter drier
B. Accumulator
C. Receiver
D. Sight glass
Rationale: Accumulators trap liquid refrigerant in suction lines.
7. What type of compressor is commonly used in residential AC
systems?
, A. Centrifugal
B. Screw
C. Scroll
D. Rotary vane
Rationale: Scroll compressors are efficient and reliable for
residential systems.
8. Which pressure is measured on the low side of a system?
A. Head pressure
B. Discharge pressure
C. Suction pressure
D. Static pressure
Rationale: Suction pressure represents evaporator pressure.
9. What happens when a system is undercharged?
A. High suction pressure
B. High head pressure
C. Low suction pressure
D. Flooded evaporator
Rationale: Insufficient refrigerant reduces evaporator pressure.
10. What is the purpose of a filter drier?
A. Increase oil return
B. Store refrigerant
C. Remove moisture and contaminants
D. Reduce pressure
Rationale: Moisture and debris can damage system components.
11. Which refrigerant is classified as an HFC?
A. R-22
B. R-12
