Georgia Refrigeration Contractor
Exam Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. Which refrigerant has the lowest ozone depletion potential (ODP)?
A. R-12
B. R-22
C. R-134a
D. R-502
Rationale: R-134a is a hydrofluorocarbon (HFC) with zero ODP,
unlike R-12 and R-22 which are chlorofluorocarbons (CFCs) or
hydrochlorofluorocarbons (HCFCs).
2. What is the primary purpose of a compressor in a refrigeration system?
A. To expand the refrigerant
B. To raise the pressure and temperature of the refrigerant vapor
C. To condense the refrigerant
D. To absorb heat from the space
Rationale: The compressor increases the pressure and temperature of
the refrigerant vapor, allowing it to release heat in the condenser.
3. Which component removes heat from the refrigerated space?
A. Condenser
B. Expansion valve
C. Evaporator
D. Compressor
Rationale: The evaporator absorbs heat from the area being cooled,
causing the refrigerant to evaporate.
4. What type of expansion device is commonly used in commercial
refrigeration systems?
A. Fixed orifice
B. Thermostatic expansion valve (TXV)
, C. Capillary tube only
D. Compressor unloading valve
Rationale: A TXV regulates the flow of refrigerant to the evaporator
based on load, improving efficiency.
5. Which safety device prevents excessive pressure in a refrigeration
system?
A. Sight glass
B. Filter drier
C. Pressure relief valve
D. Accumulator
Rationale: Pressure relief valves protect the system from dangerous
overpressure conditions.
6. What is the purpose of a filter-drier?
A. Increase refrigerant flow
B. Measure refrigerant pressure
C. Remove moisture and contaminants from the refrigerant
D. Control compressor speed
Rationale: Filter-driers prevent moisture and particulate matter from
damaging components.
7. What is superheat in a refrigeration system?
A. Temperature of refrigerant in the condenser
B. Temperature of vapor above its saturation point at the
evaporator exit
C. Pressure difference across the expansion valve
D. Temperature of liquid refrigerant leaving the condenser
Rationale: Superheat indicates the vapor has absorbed enough heat
to fully evaporate, protecting the compressor from liquid slugging.
8. What is the function of a condenser in a refrigeration system?
A. Absorb heat from the cooled space
B. Reject heat from the refrigerant to the surrounding air or water
C. Increase evaporator pressure
D. Regulate refrigerant flow
Rationale: The condenser transfers heat from the refrigerant to the
environment, causing the refrigerant to condense.
9. Which type of refrigerant is considered a Class A1, non-toxic, non-
flammable refrigerant?
A. R-22
, B. R-134a
C. R-290
D. R-600a
Rationale: R-134a is classified A1, meaning it is safe for toxicity and
flammability under normal conditions.
10. What is the primary effect of low refrigerant charge in a system?
A. Freezing of the condenser
B. Reduced cooling capacity and possible compressor damage
C. Increased condenser pressure
D. Increased superheat in the condenser
Rationale: Low refrigerant charge reduces heat absorption in the
evaporator and can lead to overheating of the compressor.
11. Which refrigerant is flammable and requires special handling?
A. R-134a
B. R-404A
C. R-22
D. R-290
Rationale: R-290 (propane) is flammable and requires proper safety
procedures during installation and servicing.
12. What instrument is used to measure system superheat?
A. Thermometer at the condenser exit
B. Pressure relief gauge
C. Temperature probe at the evaporator outlet and pressure gauge
D. Flow meter
Rationale: Superheat is calculated using the evaporator outlet
temperature and the corresponding saturation temperature from the
pressure gauge.
13. What is the purpose of an accumulator in a refrigeration system?
A. Increase system pressure
B. Control refrigerant flow to the condenser
C. Prevent liquid refrigerant from entering the compressor
D. Reduce energy consumption
Rationale: Accumulators trap liquid refrigerant, allowing only vapor
to enter the compressor and preventing damage.
14. Which refrigerant type is commonly used in low-temperature
applications like freezers?
A. R-410A
Exam Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. Which refrigerant has the lowest ozone depletion potential (ODP)?
A. R-12
B. R-22
C. R-134a
D. R-502
Rationale: R-134a is a hydrofluorocarbon (HFC) with zero ODP,
unlike R-12 and R-22 which are chlorofluorocarbons (CFCs) or
hydrochlorofluorocarbons (HCFCs).
2. What is the primary purpose of a compressor in a refrigeration system?
A. To expand the refrigerant
B. To raise the pressure and temperature of the refrigerant vapor
C. To condense the refrigerant
D. To absorb heat from the space
Rationale: The compressor increases the pressure and temperature of
the refrigerant vapor, allowing it to release heat in the condenser.
3. Which component removes heat from the refrigerated space?
A. Condenser
B. Expansion valve
C. Evaporator
D. Compressor
Rationale: The evaporator absorbs heat from the area being cooled,
causing the refrigerant to evaporate.
4. What type of expansion device is commonly used in commercial
refrigeration systems?
A. Fixed orifice
B. Thermostatic expansion valve (TXV)
, C. Capillary tube only
D. Compressor unloading valve
Rationale: A TXV regulates the flow of refrigerant to the evaporator
based on load, improving efficiency.
5. Which safety device prevents excessive pressure in a refrigeration
system?
A. Sight glass
B. Filter drier
C. Pressure relief valve
D. Accumulator
Rationale: Pressure relief valves protect the system from dangerous
overpressure conditions.
6. What is the purpose of a filter-drier?
A. Increase refrigerant flow
B. Measure refrigerant pressure
C. Remove moisture and contaminants from the refrigerant
D. Control compressor speed
Rationale: Filter-driers prevent moisture and particulate matter from
damaging components.
7. What is superheat in a refrigeration system?
A. Temperature of refrigerant in the condenser
B. Temperature of vapor above its saturation point at the
evaporator exit
C. Pressure difference across the expansion valve
D. Temperature of liquid refrigerant leaving the condenser
Rationale: Superheat indicates the vapor has absorbed enough heat
to fully evaporate, protecting the compressor from liquid slugging.
8. What is the function of a condenser in a refrigeration system?
A. Absorb heat from the cooled space
B. Reject heat from the refrigerant to the surrounding air or water
C. Increase evaporator pressure
D. Regulate refrigerant flow
Rationale: The condenser transfers heat from the refrigerant to the
environment, causing the refrigerant to condense.
9. Which type of refrigerant is considered a Class A1, non-toxic, non-
flammable refrigerant?
A. R-22
, B. R-134a
C. R-290
D. R-600a
Rationale: R-134a is classified A1, meaning it is safe for toxicity and
flammability under normal conditions.
10. What is the primary effect of low refrigerant charge in a system?
A. Freezing of the condenser
B. Reduced cooling capacity and possible compressor damage
C. Increased condenser pressure
D. Increased superheat in the condenser
Rationale: Low refrigerant charge reduces heat absorption in the
evaporator and can lead to overheating of the compressor.
11. Which refrigerant is flammable and requires special handling?
A. R-134a
B. R-404A
C. R-22
D. R-290
Rationale: R-290 (propane) is flammable and requires proper safety
procedures during installation and servicing.
12. What instrument is used to measure system superheat?
A. Thermometer at the condenser exit
B. Pressure relief gauge
C. Temperature probe at the evaporator outlet and pressure gauge
D. Flow meter
Rationale: Superheat is calculated using the evaporator outlet
temperature and the corresponding saturation temperature from the
pressure gauge.
13. What is the purpose of an accumulator in a refrigeration system?
A. Increase system pressure
B. Control refrigerant flow to the condenser
C. Prevent liquid refrigerant from entering the compressor
D. Reduce energy consumption
Rationale: Accumulators trap liquid refrigerant, allowing only vapor
to enter the compressor and preventing damage.
14. Which refrigerant type is commonly used in low-temperature
applications like freezers?
A. R-410A
