Wisconsin Refrigeration Systems Contractor
Examination Questions and Correct Answers
(Verified Answers) Plus Rationale 2027 Q&A|
Instant Download Pdf
Question 1
Which refrigerant property is most directly related to the temperature
at which a refrigerant changes from liquid to vapor at a given pressure?
A. Specific heat
B. Saturation temperature
C. Density
D. Viscosity
Rationale: Saturation temperature is the temperature corresponding
to a refrigerant's boiling or condensing point at a particular pressure.
Understanding the pressure-temperature relationship is fundamental
to diagnosing and servicing refrigeration systems.
Question 2
,In a basic vapor-compression refrigeration system, which component
raises the pressure of the refrigerant vapor?
A. Evaporator
B. Condenser
C. Expansion device
D. Compressor
Rationale: The compressor draws low-pressure refrigerant vapor from
the evaporator and compresses it into a high-pressure, high-
temperature vapor before it enters the condenser.
Question 3
What is the primary function of the evaporator?
A. Reject heat to the surrounding air
B. Increase refrigerant pressure
C. Absorb heat from the refrigerated space or product
D. Remove oil from the refrigerant
Rationale: The evaporator is the heat-absorbing component.
Refrigerant boils inside the evaporator as it absorbs heat from the air,
product, water, or other medium being cooled.
Question 4
,What is the primary function of the condenser in a refrigeration
system?
A. Lower refrigerant pressure
B. Reject heat from the refrigerant
C. Increase evaporator temperature
D. Meter refrigerant into the compressor
Rationale: The condenser removes heat from the high-pressure
refrigerant vapor. As heat is rejected, the vapor condenses into a high-
pressure liquid.
Question 5
Which component controls the amount of refrigerant entering many
evaporators?
A. Receiver
B. Accumulator
C. Condenser
D. Expansion device
Rationale: A thermostatic expansion valve, electronic expansion valve,
or similar metering device regulates refrigerant flow into the
evaporator while producing the required pressure drop.
Question 6
, What happens to refrigerant pressure as it passes through a typical
expansion device?
A. It increases substantially
B. It remains exactly constant
C. It decreases substantially
D. It becomes atmospheric
Rationale: The expansion device creates a restriction between the
high-pressure liquid side and the low-pressure evaporator side. The
resulting pressure drop causes part of the liquid refrigerant to flash
into vapor.
Question 7
Superheat is best described as:
A. The temperature below the refrigerant's freezing point
B. The difference between condensing and evaporating pressures
C. The temperature of vapor above its saturation temperature at a
given pressure
D. The temperature difference between compressor discharge and
suction
Rationale: Superheat indicates how much a vapor's actual
temperature exceeds its saturation temperature. It is particularly
Examination Questions and Correct Answers
(Verified Answers) Plus Rationale 2027 Q&A|
Instant Download Pdf
Question 1
Which refrigerant property is most directly related to the temperature
at which a refrigerant changes from liquid to vapor at a given pressure?
A. Specific heat
B. Saturation temperature
C. Density
D. Viscosity
Rationale: Saturation temperature is the temperature corresponding
to a refrigerant's boiling or condensing point at a particular pressure.
Understanding the pressure-temperature relationship is fundamental
to diagnosing and servicing refrigeration systems.
Question 2
,In a basic vapor-compression refrigeration system, which component
raises the pressure of the refrigerant vapor?
A. Evaporator
B. Condenser
C. Expansion device
D. Compressor
Rationale: The compressor draws low-pressure refrigerant vapor from
the evaporator and compresses it into a high-pressure, high-
temperature vapor before it enters the condenser.
Question 3
What is the primary function of the evaporator?
A. Reject heat to the surrounding air
B. Increase refrigerant pressure
C. Absorb heat from the refrigerated space or product
D. Remove oil from the refrigerant
Rationale: The evaporator is the heat-absorbing component.
Refrigerant boils inside the evaporator as it absorbs heat from the air,
product, water, or other medium being cooled.
Question 4
,What is the primary function of the condenser in a refrigeration
system?
A. Lower refrigerant pressure
B. Reject heat from the refrigerant
C. Increase evaporator temperature
D. Meter refrigerant into the compressor
Rationale: The condenser removes heat from the high-pressure
refrigerant vapor. As heat is rejected, the vapor condenses into a high-
pressure liquid.
Question 5
Which component controls the amount of refrigerant entering many
evaporators?
A. Receiver
B. Accumulator
C. Condenser
D. Expansion device
Rationale: A thermostatic expansion valve, electronic expansion valve,
or similar metering device regulates refrigerant flow into the
evaporator while producing the required pressure drop.
Question 6
, What happens to refrigerant pressure as it passes through a typical
expansion device?
A. It increases substantially
B. It remains exactly constant
C. It decreases substantially
D. It becomes atmospheric
Rationale: The expansion device creates a restriction between the
high-pressure liquid side and the low-pressure evaporator side. The
resulting pressure drop causes part of the liquid refrigerant to flash
into vapor.
Question 7
Superheat is best described as:
A. The temperature below the refrigerant's freezing point
B. The difference between condensing and evaporating pressures
C. The temperature of vapor above its saturation temperature at a
given pressure
D. The temperature difference between compressor discharge and
suction
Rationale: Superheat indicates how much a vapor's actual
temperature exceeds its saturation temperature. It is particularly
