Refrigeration Contractor Licensing Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. A refrigeration contractor is designing a vapor-compression system for a
commercial cold room. Which component is primarily responsible for
increasing the pressure and temperature of the refrigerant vapor leaving the
evaporator?
A. Expansion valve
B. Compressor
C. Condenser
D. Receiver
B
The compressor is the central mechanical device in a vapor-compression
refrigeration cycle that draws in low-pressure refrigerant vapor from the
evaporator and compresses it into a high-pressure, high-temperature
vapor, enabling heat rejection in the condenser.
, 2. In a refrigeration cycle, 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 from the refrigerant to the surrounding environment
D. To regulate refrigerant flow into the compressor
C
The condenser’s main function is to remove heat from the high-pressure
refrigerant vapor, causing it to condense into a liquid by transferring
thermal energy to the surrounding air or water medium.
3. Which refrigerant property is most important when selecting a
refrigerant for low-temperature applications?
A. High specific heat capacity in liquid state
B. Low boiling point at atmospheric pressure
C. High electrical conductivity
D. High viscosity
B
A low boiling point allows the refrigerant to evaporate at low
temperatures, making it suitable for applications such as freezers and deep
refrigeration systems where extremely low temperatures are required.
4. What is the purpose of superheating refrigerant vapor at the
evaporator outlet?
,A. To ensure complete evaporation and prevent liquid refrigerant from
entering the compressor
B. To increase condenser pressure
C. To reduce compressor efficiency
D. To decrease heat transfer rate in the evaporator
A
Superheating ensures that only vapor enters the compressor, preventing
liquid slugging which can damage compressor components and reduce
system reliability.
5. Which device controls the amount of refrigerant entering the
evaporator?
A. Compressor
B. Expansion valve
C. Condenser fan
D. Accumulator
B
The expansion valve regulates refrigerant flow into the evaporator by
reducing pressure and controlling the rate at which liquid refrigerant
enters the low-pressure side of the system.
6. What is the effect of undercharging a refrigeration system?
, A. Increased cooling capacity
B. Reduced evaporator pressure and possible coil icing
C. Increased condenser efficiency
D. Higher compressor discharge pressure
B
An undercharged system has insufficient refrigerant, leading to low
evaporator pressure, reduced cooling performance, and potential coil
freezing due to excessive temperature drop.
7. Which safety device is commonly used to protect a refrigeration
compressor from excessive pressure?
A. Thermostat
B. Pressure relief valve
C. Expansion valve
D. Sight glass
B
A pressure relief valve opens when system pressure exceeds safe limits,
preventing equipment damage and ensuring safe operation under
abnormal conditions.
8. What is the primary purpose of a receiver in a refrigeration system?
A. To compress refrigerant
B. To store liquid refrigerant
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. A refrigeration contractor is designing a vapor-compression system for a
commercial cold room. Which component is primarily responsible for
increasing the pressure and temperature of the refrigerant vapor leaving the
evaporator?
A. Expansion valve
B. Compressor
C. Condenser
D. Receiver
B
The compressor is the central mechanical device in a vapor-compression
refrigeration cycle that draws in low-pressure refrigerant vapor from the
evaporator and compresses it into a high-pressure, high-temperature
vapor, enabling heat rejection in the condenser.
, 2. In a refrigeration cycle, 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 from the refrigerant to the surrounding environment
D. To regulate refrigerant flow into the compressor
C
The condenser’s main function is to remove heat from the high-pressure
refrigerant vapor, causing it to condense into a liquid by transferring
thermal energy to the surrounding air or water medium.
3. Which refrigerant property is most important when selecting a
refrigerant for low-temperature applications?
A. High specific heat capacity in liquid state
B. Low boiling point at atmospheric pressure
C. High electrical conductivity
D. High viscosity
B
A low boiling point allows the refrigerant to evaporate at low
temperatures, making it suitable for applications such as freezers and deep
refrigeration systems where extremely low temperatures are required.
4. What is the purpose of superheating refrigerant vapor at the
evaporator outlet?
,A. To ensure complete evaporation and prevent liquid refrigerant from
entering the compressor
B. To increase condenser pressure
C. To reduce compressor efficiency
D. To decrease heat transfer rate in the evaporator
A
Superheating ensures that only vapor enters the compressor, preventing
liquid slugging which can damage compressor components and reduce
system reliability.
5. Which device controls the amount of refrigerant entering the
evaporator?
A. Compressor
B. Expansion valve
C. Condenser fan
D. Accumulator
B
The expansion valve regulates refrigerant flow into the evaporator by
reducing pressure and controlling the rate at which liquid refrigerant
enters the low-pressure side of the system.
6. What is the effect of undercharging a refrigeration system?
, A. Increased cooling capacity
B. Reduced evaporator pressure and possible coil icing
C. Increased condenser efficiency
D. Higher compressor discharge pressure
B
An undercharged system has insufficient refrigerant, leading to low
evaporator pressure, reduced cooling performance, and potential coil
freezing due to excessive temperature drop.
7. Which safety device is commonly used to protect a refrigeration
compressor from excessive pressure?
A. Thermostat
B. Pressure relief valve
C. Expansion valve
D. Sight glass
B
A pressure relief valve opens when system pressure exceeds safe limits,
preventing equipment damage and ensuring safe operation under
abnormal conditions.
8. What is the primary purpose of a receiver in a refrigeration system?
A. To compress refrigerant
B. To store liquid refrigerant
