California C-38 Refrigeration Contractor
Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. What is the primary purpose of a refrigeration system?
A. To create cold air by eliminating all heat
B. To transfer heat from a lower-temperature area to a higher-
temperature area
C. To convert electrical energy directly into cold
D. To increase the temperature of the refrigerated space
Rationale: Refrigeration removes heat from a space or substance and
transfers it to another location, usually outdoors. The refrigeration
cycle requires energy, typically supplied to the compressor, to move
heat against its natural direction of flow.
,2. Which component is responsible for compressing refrigerant vapor
and increasing its pressure?
A. Evaporator
B. Condenser
C. Compressor
D. Expansion valve
Rationale: The compressor draws low-pressure refrigerant vapor from
the evaporator and compresses it into high-pressure, high-
temperature vapor. This pressure increase allows the refrigerant to
reject heat at a temperature above the surrounding air or cooling
medium.
3. What happens to refrigerant in the evaporator during normal
operation?
A. It rejects heat and condenses into liquid
B. It absorbs heat and boils into vapor
C. It increases in pressure through compression
D. It releases heat while remaining entirely liquid
Rationale: The evaporator is the heat-absorbing component. Low-
pressure refrigerant absorbs heat from the refrigerated space and
,changes from a liquid-vapor mixture into vapor. This heat absorption
produces the desired cooling effect.
4. What is the primary function of the condenser?
A. To reduce refrigerant pressure
B. To absorb heat from the refrigerated space
C. To reject heat and condense refrigerant vapor into liquid
D. To increase refrigerant superheat
Rationale: The condenser removes heat from the hot, high-pressure
refrigerant vapor. As the refrigerant rejects heat, it condenses into a
liquid. The rejected heat includes both the heat absorbed in the
evaporator and the energy added by the compressor.
5. Which sequence correctly represents the basic vapor-compression
refrigeration cycle?
A. Condenser, evaporator, compressor, expansion device
B. Evaporator, condenser, expansion device, compressor
C. Compressor, condenser, expansion device, evaporator
D. Expansion device, compressor, evaporator, condenser
Rationale: Refrigerant leaves the compressor as high-pressure vapor,
passes through the condenser where it rejects heat, flows through the
, expansion device where its pressure drops, and enters the evaporator
to absorb heat. The vapor then returns to the compressor to repeat
the cycle.
6. What is the main purpose of a thermostatic expansion valve (TXV)?
A. To regulate condenser fan speed
B. To control refrigerant flow into the evaporator in response to
evaporator conditions
C. To increase compressor discharge pressure
D. To remove moisture from refrigerant
Rationale: A TXV meters refrigerant into the evaporator to maintain
an appropriate level of superheat at the evaporator outlet. Proper
metering helps use the evaporator effectively while limiting the risk of
liquid refrigerant returning to the compressor.
7. What does superheat measure?
A. The temperature of liquid refrigerant below its saturation
temperature
B. The temperature of refrigerant vapor above its saturation
temperature at a given pressure
Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. What is the primary purpose of a refrigeration system?
A. To create cold air by eliminating all heat
B. To transfer heat from a lower-temperature area to a higher-
temperature area
C. To convert electrical energy directly into cold
D. To increase the temperature of the refrigerated space
Rationale: Refrigeration removes heat from a space or substance and
transfers it to another location, usually outdoors. The refrigeration
cycle requires energy, typically supplied to the compressor, to move
heat against its natural direction of flow.
,2. Which component is responsible for compressing refrigerant vapor
and increasing its pressure?
A. Evaporator
B. Condenser
C. Compressor
D. Expansion valve
Rationale: The compressor draws low-pressure refrigerant vapor from
the evaporator and compresses it into high-pressure, high-
temperature vapor. This pressure increase allows the refrigerant to
reject heat at a temperature above the surrounding air or cooling
medium.
3. What happens to refrigerant in the evaporator during normal
operation?
A. It rejects heat and condenses into liquid
B. It absorbs heat and boils into vapor
C. It increases in pressure through compression
D. It releases heat while remaining entirely liquid
Rationale: The evaporator is the heat-absorbing component. Low-
pressure refrigerant absorbs heat from the refrigerated space and
,changes from a liquid-vapor mixture into vapor. This heat absorption
produces the desired cooling effect.
4. What is the primary function of the condenser?
A. To reduce refrigerant pressure
B. To absorb heat from the refrigerated space
C. To reject heat and condense refrigerant vapor into liquid
D. To increase refrigerant superheat
Rationale: The condenser removes heat from the hot, high-pressure
refrigerant vapor. As the refrigerant rejects heat, it condenses into a
liquid. The rejected heat includes both the heat absorbed in the
evaporator and the energy added by the compressor.
5. Which sequence correctly represents the basic vapor-compression
refrigeration cycle?
A. Condenser, evaporator, compressor, expansion device
B. Evaporator, condenser, expansion device, compressor
C. Compressor, condenser, expansion device, evaporator
D. Expansion device, compressor, evaporator, condenser
Rationale: Refrigerant leaves the compressor as high-pressure vapor,
passes through the condenser where it rejects heat, flows through the
, expansion device where its pressure drops, and enters the evaporator
to absorb heat. The vapor then returns to the compressor to repeat
the cycle.
6. What is the main purpose of a thermostatic expansion valve (TXV)?
A. To regulate condenser fan speed
B. To control refrigerant flow into the evaporator in response to
evaporator conditions
C. To increase compressor discharge pressure
D. To remove moisture from refrigerant
Rationale: A TXV meters refrigerant into the evaporator to maintain
an appropriate level of superheat at the evaporator outlet. Proper
metering helps use the evaporator effectively while limiting the risk of
liquid refrigerant returning to the compressor.
7. What does superheat measure?
A. The temperature of liquid refrigerant below its saturation
temperature
B. The temperature of refrigerant vapor above its saturation
temperature at a given pressure
