CT Refrigeration Contractor Exam
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A| Instant Download Pdf
1. Which of the following is the most common refrigerant used in
residential air conditioning systems today?
A. R-22
B. R-134a
C. R-410A
D. R-12
Rationale: R-410A is widely used today because it is more
environmentally friendly than R-22 and has higher efficiency.
2. What is the primary purpose of the expansion device in a refrigeration
system?
A. Increase refrigerant pressure
B. Compress refrigerant
C. Reduce refrigerant pressure and control flow into the
evaporator
D. Heat the refrigerant
Rationale: The expansion device lowers refrigerant pressure,
allowing it to evaporate and absorb heat in the evaporator.
3. Which component of a refrigeration system removes heat from the
refrigerant? A. Compressor
B. Condenser
C. Expansion valve
D. Evaporator
Rationale: The condenser removes heat from high-pressure
, refrigerant vapor and transfers it to the surrounding air or water.
4. In a refrigeration cycle, what state is the refrigerant in when it leaves
the compressor? A. Low-pressure gas
B. High-pressure gas
C. Low-pressure liquid
D. High-pressure liquid
Rationale: The compressor raises the refrigerant pressure and
temperature, resulting in high-pressure gas.
5. What type of compressor is commonly used in large commercial
refrigeration systems?
A. Reciprocating
B. Screw
C. Centrifugal
D. Rotary
Rationale: Screw compressors are common in large systems due to
high capacity and efficiency.
6. What is the main purpose of a receiver in a refrigeration system?
A. Compress refrigerant
B. Store liquid refrigerant
C. Evaporate refrigerant
D. Control refrigerant flow
Rationale: A receiver temporarily stores liquid refrigerant and
ensures a steady supply to the expansion device.
7. Which of the following is a safety device commonly installed in
refrigeration systems?
A. Sight glass
B. Filter-drier
C. High-pressure cutout switch
D. Thermostat
Rationale: High-pressure cutout switches prevent compressor
damage from excessive pressure.
8. What does superheat indicate in a refrigeration system?
A. Temperature of refrigerant in the condenser
, B. Amount the refrigerant vapor is heated above its saturation
temperature at the evaporator outlet C. Temperature of the
ambient air
D. Degree of refrigerant subcooling
Rationale: Superheat ensures that only vapor enters the compressor,
preventing liquid slugging.
9. Which of the following best describes subcooling in a refrigeration
system?
A. Refrigerant vapor is heated above saturation
B. Refrigerant liquid is cooled below saturation temperature
C. Refrigerant is compressed
D. Refrigerant absorbs heat in the evaporator
Rationale: Subcooling improves system efficiency and prevents
flashing at the expansion valve.
10. Which refrigerant is classified as a hydrofluorocarbon (HFC)?
A. R-22
B. R-134a
C. R-12
D. Ammonia
Rationale: R-134a is an HFC refrigerant, which contains no chlorine
and has lower ozone depletion potential.
11. What is the primary hazard associated with ammonia (R-717)
refrigerant?
A. Flammable
B. Toxic and corrosive
C. Low efficiency
D. Ozone-depleting
Rationale: Ammonia is highly toxic and can cause irritation or
poisoning; proper handling and ventilation are critical.
12. Which component removes moisture and contaminants from
the refrigerant? A. Receiver
B. Sight glass
C. Filter-drier
D. Expansion valve
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A| Instant Download Pdf
1. Which of the following is the most common refrigerant used in
residential air conditioning systems today?
A. R-22
B. R-134a
C. R-410A
D. R-12
Rationale: R-410A is widely used today because it is more
environmentally friendly than R-22 and has higher efficiency.
2. What is the primary purpose of the expansion device in a refrigeration
system?
A. Increase refrigerant pressure
B. Compress refrigerant
C. Reduce refrigerant pressure and control flow into the
evaporator
D. Heat the refrigerant
Rationale: The expansion device lowers refrigerant pressure,
allowing it to evaporate and absorb heat in the evaporator.
3. Which component of a refrigeration system removes heat from the
refrigerant? A. Compressor
B. Condenser
C. Expansion valve
D. Evaporator
Rationale: The condenser removes heat from high-pressure
, refrigerant vapor and transfers it to the surrounding air or water.
4. In a refrigeration cycle, what state is the refrigerant in when it leaves
the compressor? A. Low-pressure gas
B. High-pressure gas
C. Low-pressure liquid
D. High-pressure liquid
Rationale: The compressor raises the refrigerant pressure and
temperature, resulting in high-pressure gas.
5. What type of compressor is commonly used in large commercial
refrigeration systems?
A. Reciprocating
B. Screw
C. Centrifugal
D. Rotary
Rationale: Screw compressors are common in large systems due to
high capacity and efficiency.
6. What is the main purpose of a receiver in a refrigeration system?
A. Compress refrigerant
B. Store liquid refrigerant
C. Evaporate refrigerant
D. Control refrigerant flow
Rationale: A receiver temporarily stores liquid refrigerant and
ensures a steady supply to the expansion device.
7. Which of the following is a safety device commonly installed in
refrigeration systems?
A. Sight glass
B. Filter-drier
C. High-pressure cutout switch
D. Thermostat
Rationale: High-pressure cutout switches prevent compressor
damage from excessive pressure.
8. What does superheat indicate in a refrigeration system?
A. Temperature of refrigerant in the condenser
, B. Amount the refrigerant vapor is heated above its saturation
temperature at the evaporator outlet C. Temperature of the
ambient air
D. Degree of refrigerant subcooling
Rationale: Superheat ensures that only vapor enters the compressor,
preventing liquid slugging.
9. Which of the following best describes subcooling in a refrigeration
system?
A. Refrigerant vapor is heated above saturation
B. Refrigerant liquid is cooled below saturation temperature
C. Refrigerant is compressed
D. Refrigerant absorbs heat in the evaporator
Rationale: Subcooling improves system efficiency and prevents
flashing at the expansion valve.
10. Which refrigerant is classified as a hydrofluorocarbon (HFC)?
A. R-22
B. R-134a
C. R-12
D. Ammonia
Rationale: R-134a is an HFC refrigerant, which contains no chlorine
and has lower ozone depletion potential.
11. What is the primary hazard associated with ammonia (R-717)
refrigerant?
A. Flammable
B. Toxic and corrosive
C. Low efficiency
D. Ozone-depleting
Rationale: Ammonia is highly toxic and can cause irritation or
poisoning; proper handling and ventilation are critical.
12. Which component removes moisture and contaminants from
the refrigerant? A. Receiver
B. Sight glass
C. Filter-drier
D. Expansion valve
