Refrigeration Engineer License Exam
With Actual Questions & Verified
Answers, Plus Explained
Rationales/Expert Verified For
Guaranteed 100% Pass 2026/Latest
Update/Instant Download Pdf
1. Which of the following is the primary function of a condenser in a
refrigeration system?
A. Absorb heat from the refrigerated space
B. Reject heat to the environment
C. Increase refrigerant pressure without heat transfer
D. Control the flow of refrigerant
Answer: B
Rationale: The condenser removes heat from the high-pressure
refrigerant vapor and rejects it to the environment, converting vapor
into liquid.
2. Which type of compressor is commonly used in large industrial
refrigeration systems?
A. Reciprocating
B. Rotary
C. Centrifugal
D. Scroll
,Answer: C
Rationale: Centrifugal compressors are used in large systems because
they handle high capacities efficiently and operate smoothly at high
speeds.
3. What does the term “superheat” refer to in refrigeration?
A. Temperature of refrigerant below its boiling point
B. Temperature of refrigerant vapor above its boiling point
C. Temperature at which the refrigerant condenses
D. Maximum allowable refrigerant temperature
Answer: B
Rationale: Superheat is the amount of heat added to vapor after it has
completely evaporated, ensuring no liquid enters the compressor.
4. Which of the following refrigerants has zero ozone depletion
potential?
A. R-12
B. R-22
C. R-134a
D. R-11
Answer: C
Rationale: R-134a is an HFC refrigerant with zero ODP, making it
environmentally safer than CFCs and HCFCs.
5. What is the main purpose of an expansion valve in a refrigeration
system?
A. Heat the refrigerant
B. Regulate refrigerant flow into the evaporator
C. Increase compressor efficiency
D. Filter impurities
,Answer: B
Rationale: The expansion valve controls the refrigerant flow to
maintain proper superheat and ensure efficient heat absorption in the
evaporator.
6. Which of the following indicates a low refrigerant charge in a
system?
A. High discharge pressure
B. Low suction pressure
C. High evaporator temperature
D. Excessive oil in the compressor
Answer: B
Rationale: Low suction pressure is a classic sign of insufficient
refrigerant, which reduces heat absorption and system capacity.
7. What is the function of a receiver in a refrigeration system?
A. Increase refrigerant pressure
B. Store liquid refrigerant
C. Remove moisture from refrigerant
D. Control system superheat
Answer: B
Rationale: The receiver stores liquid refrigerant to ensure a steady
supply to the expansion device.
8. What type of heat exchanger is commonly used in ammonia
refrigeration systems?
A. Plate-fin
B. Shell-and-tube
C. Flooded evaporator
D. Air-cooled finned tube
, Answer: C
Rationale: Flooded evaporators are widely used with ammonia
because they provide efficient heat transfer and maintain liquid
refrigerant coverage.
9. Which of the following is a sign of liquid refrigerant entering the
compressor?
A. Low discharge temperature
B. High suction pressure
C. Liquid slugging
D. Normal operation
Answer: C
Rationale: Liquid slugging occurs when liquid refrigerant enters the
compressor, potentially causing mechanical damage.
10. What is the typical pressure-temperature relationship in a
saturated ammonia system?
A. Linear
B. Exponential
C. Non-linear
D. Constant
Answer: C
Rationale: Ammonia’s pressure-temperature curve is non-linear,
meaning small temperature changes can cause large pressure
changes.
11. Which component prevents oil from returning to the
compressor suction line in ammonia systems?
A. Expansion valve
B. Condenser
With Actual Questions & Verified
Answers, Plus Explained
Rationales/Expert Verified For
Guaranteed 100% Pass 2026/Latest
Update/Instant Download Pdf
1. Which of the following is the primary function of a condenser in a
refrigeration system?
A. Absorb heat from the refrigerated space
B. Reject heat to the environment
C. Increase refrigerant pressure without heat transfer
D. Control the flow of refrigerant
Answer: B
Rationale: The condenser removes heat from the high-pressure
refrigerant vapor and rejects it to the environment, converting vapor
into liquid.
2. Which type of compressor is commonly used in large industrial
refrigeration systems?
A. Reciprocating
B. Rotary
C. Centrifugal
D. Scroll
,Answer: C
Rationale: Centrifugal compressors are used in large systems because
they handle high capacities efficiently and operate smoothly at high
speeds.
3. What does the term “superheat” refer to in refrigeration?
A. Temperature of refrigerant below its boiling point
B. Temperature of refrigerant vapor above its boiling point
C. Temperature at which the refrigerant condenses
D. Maximum allowable refrigerant temperature
Answer: B
Rationale: Superheat is the amount of heat added to vapor after it has
completely evaporated, ensuring no liquid enters the compressor.
4. Which of the following refrigerants has zero ozone depletion
potential?
A. R-12
B. R-22
C. R-134a
D. R-11
Answer: C
Rationale: R-134a is an HFC refrigerant with zero ODP, making it
environmentally safer than CFCs and HCFCs.
5. What is the main purpose of an expansion valve in a refrigeration
system?
A. Heat the refrigerant
B. Regulate refrigerant flow into the evaporator
C. Increase compressor efficiency
D. Filter impurities
,Answer: B
Rationale: The expansion valve controls the refrigerant flow to
maintain proper superheat and ensure efficient heat absorption in the
evaporator.
6. Which of the following indicates a low refrigerant charge in a
system?
A. High discharge pressure
B. Low suction pressure
C. High evaporator temperature
D. Excessive oil in the compressor
Answer: B
Rationale: Low suction pressure is a classic sign of insufficient
refrigerant, which reduces heat absorption and system capacity.
7. What is the function of a receiver in a refrigeration system?
A. Increase refrigerant pressure
B. Store liquid refrigerant
C. Remove moisture from refrigerant
D. Control system superheat
Answer: B
Rationale: The receiver stores liquid refrigerant to ensure a steady
supply to the expansion device.
8. What type of heat exchanger is commonly used in ammonia
refrigeration systems?
A. Plate-fin
B. Shell-and-tube
C. Flooded evaporator
D. Air-cooled finned tube
, Answer: C
Rationale: Flooded evaporators are widely used with ammonia
because they provide efficient heat transfer and maintain liquid
refrigerant coverage.
9. Which of the following is a sign of liquid refrigerant entering the
compressor?
A. Low discharge temperature
B. High suction pressure
C. Liquid slugging
D. Normal operation
Answer: C
Rationale: Liquid slugging occurs when liquid refrigerant enters the
compressor, potentially causing mechanical damage.
10. What is the typical pressure-temperature relationship in a
saturated ammonia system?
A. Linear
B. Exponential
C. Non-linear
D. Constant
Answer: C
Rationale: Ammonia’s pressure-temperature curve is non-linear,
meaning small temperature changes can cause large pressure
changes.
11. Which component prevents oil from returning to the
compressor suction line in ammonia systems?
A. Expansion valve
B. Condenser
