AR HVACR Heating, Ventilation, AC &
Refrigeration Contractor Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales 2027
Q&A | Instant Download Pdf
1. What is the primary purpose of a thermostat in an HVAC system?
A. Increase refrigerant pressure
B. Control airflow through the ductwork
C. Sense space temperature and control heating or cooling operation
D. Remove moisture from refrigerant
Answer: C. Sense space temperature and control heating or cooling
operation
Rationale: A thermostat monitors the conditioned space temperature and
signals the HVAC equipment to operate when heating or cooling is
required.
, 2. Which component of a vapor-compression refrigeration system
removes heat from the conditioned space?
A. Condenser
B. Evaporator
C. Compressor
D. Receiver
Answer: B. Evaporator
Rationale: The evaporator absorbs heat from the air or process being
cooled as refrigerant changes from liquid to vapor.
3. What is the primary function of the compressor?
A. Reduce refrigerant temperature
B. Meter refrigerant into the evaporator
C. Increase refrigerant pressure and circulate refrigerant
D. Remove contaminants from the system
Answer: C. Increase refrigerant pressure and circulate refrigerant
Rationale: The compressor raises the pressure and temperature of
refrigerant vapor and drives refrigerant circulation through the system.
4. Which component rejects heat from the refrigerant to the surrounding
environment?
,A. Evaporator
B. Condenser
C. Expansion valve
D. Accumulator
Answer: B. Condenser
Rationale: The condenser transfers heat from the high-pressure refrigerant
to outdoor air, water, or another heat-rejection medium.
5. What is the purpose of a metering device in a refrigeration system?
A. Increase compressor speed
B. Control refrigerant flow into the evaporator
C. Remove oil from the compressor
D. Increase condenser airflow
Answer: B. Control refrigerant flow into the evaporator
Rationale: The metering device creates a pressure drop and regulates the
amount of refrigerant entering the evaporator.
6. What does superheat represent?
A. Liquid refrigerant temperature below saturation
B. Vapor temperature above its saturation temperature
, C. Condenser temperature below outdoor temperature
D. Compressor temperature below suction temperature
Answer: B. Vapor temperature above its saturation temperature
Rationale: Superheat is the amount by which a refrigerant vapor's actual
temperature exceeds its saturation temperature at the measured pressure.
7. What does subcooling indicate?
A. Vapor above its saturation temperature
B. Liquid below its saturation temperature
C. Vapor below atmospheric pressure
D. Compressor oil temperature
Answer: B. Liquid below its saturation temperature
Rationale: Subcooling is the difference between the refrigerant's
saturation temperature and the actual temperature of liquid refrigerant.
8. What is the purpose of a filter-drier?
A. Increase airflow
B. Remove moisture and contaminants from the refrigerant circuit
C. Increase refrigerant charge
D. Reduce electrical voltage
Answer: B. Remove moisture and contaminants from the refrigerant circuit
Refrigeration Contractor Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales 2027
Q&A | Instant Download Pdf
1. What is the primary purpose of a thermostat in an HVAC system?
A. Increase refrigerant pressure
B. Control airflow through the ductwork
C. Sense space temperature and control heating or cooling operation
D. Remove moisture from refrigerant
Answer: C. Sense space temperature and control heating or cooling
operation
Rationale: A thermostat monitors the conditioned space temperature and
signals the HVAC equipment to operate when heating or cooling is
required.
, 2. Which component of a vapor-compression refrigeration system
removes heat from the conditioned space?
A. Condenser
B. Evaporator
C. Compressor
D. Receiver
Answer: B. Evaporator
Rationale: The evaporator absorbs heat from the air or process being
cooled as refrigerant changes from liquid to vapor.
3. What is the primary function of the compressor?
A. Reduce refrigerant temperature
B. Meter refrigerant into the evaporator
C. Increase refrigerant pressure and circulate refrigerant
D. Remove contaminants from the system
Answer: C. Increase refrigerant pressure and circulate refrigerant
Rationale: The compressor raises the pressure and temperature of
refrigerant vapor and drives refrigerant circulation through the system.
4. Which component rejects heat from the refrigerant to the surrounding
environment?
,A. Evaporator
B. Condenser
C. Expansion valve
D. Accumulator
Answer: B. Condenser
Rationale: The condenser transfers heat from the high-pressure refrigerant
to outdoor air, water, or another heat-rejection medium.
5. What is the purpose of a metering device in a refrigeration system?
A. Increase compressor speed
B. Control refrigerant flow into the evaporator
C. Remove oil from the compressor
D. Increase condenser airflow
Answer: B. Control refrigerant flow into the evaporator
Rationale: The metering device creates a pressure drop and regulates the
amount of refrigerant entering the evaporator.
6. What does superheat represent?
A. Liquid refrigerant temperature below saturation
B. Vapor temperature above its saturation temperature
, C. Condenser temperature below outdoor temperature
D. Compressor temperature below suction temperature
Answer: B. Vapor temperature above its saturation temperature
Rationale: Superheat is the amount by which a refrigerant vapor's actual
temperature exceeds its saturation temperature at the measured pressure.
7. What does subcooling indicate?
A. Vapor above its saturation temperature
B. Liquid below its saturation temperature
C. Vapor below atmospheric pressure
D. Compressor oil temperature
Answer: B. Liquid below its saturation temperature
Rationale: Subcooling is the difference between the refrigerant's
saturation temperature and the actual temperature of liquid refrigerant.
8. What is the purpose of a filter-drier?
A. Increase airflow
B. Remove moisture and contaminants from the refrigerant circuit
C. Increase refrigerant charge
D. Reduce electrical voltage
Answer: B. Remove moisture and contaminants from the refrigerant circuit
