Indiana Refrigeration Contractor Exam
Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. Which refrigerant safety classification indicates low toxicity and no
flame propagation?
A. A2L
B. B1
C. A3
D. B2
Correct Answer: A. A1
Rationale: A1 refrigerants have low toxicity and are non-flammable,
making them common in commercial refrigeration systems.
2. What device protects a refrigeration compressor from excessive
discharge pressure?
A. Suction accumulator
B. Crankcase heater
C. Expansion valve
D. High-pressure cutout
Correct Answer: D. High-pressure cutout
Rationale: High-pressure cutouts shut down the compressor when
discharge pressure exceeds safe limits.
3. Which component meters refrigerant into the evaporator?
A. Condenser
B. Receiver
C. Expansion valve
D. Oil separator
, Correct Answer: C. Expansion valve
Rationale: The expansion valve regulates refrigerant flow based on
evaporator load.
4. What is the primary purpose of superheating refrigerant vapor?
A. Increase system capacity
B. Prevent liquid floodback
C. Reduce head pressure
D. Increase oil viscosity
Correct Answer: B. Prevent liquid floodback
Rationale: Superheating ensures refrigerant is fully vaporized before
reaching the compressor.
5. Which type of compressor is most commonly used in small
commercial refrigeration?
A. Centrifugal
B. Screw
C. Reciprocating
D. Absorption
Correct Answer: C. Reciprocating
Rationale: Reciprocating compressors are reliable and well-suited for
small to medium systems.
6. What condition results from insufficient refrigerant charge?
A. High suction pressure
B. Flooded evaporator
C. Low suction pressure
D. Excessive subcooling
Correct Answer: C. Low suction pressure
Rationale: Low refrigerant reduces evaporator pressure and cooling
capacity.
7. Which instrument is used to measure superheat?
A. Vacuum gauge
B. Thermometer and pressure gauge
C. Anemometer
D. Hygrometer
Correct Answer: B. Thermometer and pressure gauge
, Rationale: Superheat is calculated from temperature and
corresponding saturation pressure.
8. What is the function of a liquid receiver?
A. Store oil
B. Separate vapor
C. Store excess liquid refrigerant
D. Reduce compressor noise
Correct Answer: C. Store excess liquid refrigerant
Rationale: Receivers hold refrigerant during pump-down or varying
load conditions.
9. Which refrigeration component rejects heat to the environment?
A. Evaporator
B. Expansion valve
C. Condenser
D. Accumulator
Correct Answer: C. Condenser
Rationale: The condenser removes heat absorbed in the evaporator
and from compression.
10. What is the primary hazard of ammonia refrigerant (R-717)?
A. Flammability
B. High cost
C. Toxicity
D. Ozone depletion
Correct Answer: C. Toxicity
Rationale: Ammonia is highly toxic, requiring strict safety controls.
11. Which control prevents compressor operation during low oil
pressure?
A. Thermostat
B. Oil pressure safety switch
C. Solenoid valve
D. Fan cycling switch
Correct Answer: B. Oil pressure safety switch
Rationale: It shuts down the compressor to prevent damage from
inadequate lubrication.
Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. Which refrigerant safety classification indicates low toxicity and no
flame propagation?
A. A2L
B. B1
C. A3
D. B2
Correct Answer: A. A1
Rationale: A1 refrigerants have low toxicity and are non-flammable,
making them common in commercial refrigeration systems.
2. What device protects a refrigeration compressor from excessive
discharge pressure?
A. Suction accumulator
B. Crankcase heater
C. Expansion valve
D. High-pressure cutout
Correct Answer: D. High-pressure cutout
Rationale: High-pressure cutouts shut down the compressor when
discharge pressure exceeds safe limits.
3. Which component meters refrigerant into the evaporator?
A. Condenser
B. Receiver
C. Expansion valve
D. Oil separator
, Correct Answer: C. Expansion valve
Rationale: The expansion valve regulates refrigerant flow based on
evaporator load.
4. What is the primary purpose of superheating refrigerant vapor?
A. Increase system capacity
B. Prevent liquid floodback
C. Reduce head pressure
D. Increase oil viscosity
Correct Answer: B. Prevent liquid floodback
Rationale: Superheating ensures refrigerant is fully vaporized before
reaching the compressor.
5. Which type of compressor is most commonly used in small
commercial refrigeration?
A. Centrifugal
B. Screw
C. Reciprocating
D. Absorption
Correct Answer: C. Reciprocating
Rationale: Reciprocating compressors are reliable and well-suited for
small to medium systems.
6. What condition results from insufficient refrigerant charge?
A. High suction pressure
B. Flooded evaporator
C. Low suction pressure
D. Excessive subcooling
Correct Answer: C. Low suction pressure
Rationale: Low refrigerant reduces evaporator pressure and cooling
capacity.
7. Which instrument is used to measure superheat?
A. Vacuum gauge
B. Thermometer and pressure gauge
C. Anemometer
D. Hygrometer
Correct Answer: B. Thermometer and pressure gauge
, Rationale: Superheat is calculated from temperature and
corresponding saturation pressure.
8. What is the function of a liquid receiver?
A. Store oil
B. Separate vapor
C. Store excess liquid refrigerant
D. Reduce compressor noise
Correct Answer: C. Store excess liquid refrigerant
Rationale: Receivers hold refrigerant during pump-down or varying
load conditions.
9. Which refrigeration component rejects heat to the environment?
A. Evaporator
B. Expansion valve
C. Condenser
D. Accumulator
Correct Answer: C. Condenser
Rationale: The condenser removes heat absorbed in the evaporator
and from compression.
10. What is the primary hazard of ammonia refrigerant (R-717)?
A. Flammability
B. High cost
C. Toxicity
D. Ozone depletion
Correct Answer: C. Toxicity
Rationale: Ammonia is highly toxic, requiring strict safety controls.
11. Which control prevents compressor operation during low oil
pressure?
A. Thermostat
B. Oil pressure safety switch
C. Solenoid valve
D. Fan cycling switch
Correct Answer: B. Oil pressure safety switch
Rationale: It shuts down the compressor to prevent damage from
inadequate lubrication.
