COMMERCIAL REFRIGERATION FOR AIR
CONDITIONING TECHNICIANS, 4TH EDITION BY
DICK WIRZ TEST BANK | CHAPTER-BY-CHAPTER
PRACTICE QUESTIONS & ANSWERS | HVAC EXAM
PREP | INSTRUCTOR RESOURCE | STUDY GUIDE PDF
SECTION 1: FUNDAMENTALS OF COMMERCIAL REFRIGERATION
Questions 1-20
1. What component in a refrigeration system removes heat from the refrigerated
space?
A. Condenser
B. Evaporator
C. Compressor
D. Receiver
Answer: B
2. The purpose of the compressor in a refrigeration system is to:
A. Absorb heat
B. Increase refrigerant pressure
C. Expand refrigerant
D. Filter the air
Answer: B
3. Which of the following is a common refrigerant used in commercial systems?
A. R-22
, B. R-410A
C. R-744 (CO₂)
D. All of the above
Answer: D
4. In a refrigeration cycle, the condenser's main function is to:
A. Lower refrigerant pressure
B. Reject heat to the surroundings
C. Store liquid refrigerant
D. Increase humidity
Answer: B
5. A thermostatic expansion valve (TXV) is used to:
A. Control refrigerant flow into the evaporator
B. Filter liquid refrigerant
C. Compress refrigerant
D. Absorb heat
Answer: A
6. What is "superheat" in refrigeration?
A. Temperature of refrigerant below saturation
B. Temperature above saturation at evaporator outlet
C. Pressure difference in compressor
D. Condenser fan speed
Answer: B
7. What tool is typically used to measure system pressures in a commercial
refrigeration unit?
A. Multimeter
B. Refrigeration gauges (manifold)
C. Thermocouple
D. Tachometer
Answer: B
8. Which of the following indicates a possible low refrigerant charge?
A. High suction pressure
B. Low superheat
, C. Frost on evaporator coil
D. Compressor overheating
Answer: C
9. A receiver in a refrigeration system is used to:
A. Store liquid refrigerant
B. Filter moisture
C. Pump refrigerant
D. Measure temperature
Answer: A
10. The term "subcooling" refers to:
A. Cooling of refrigerant below its boiling point
B. Heating of the compressor discharge line
C. Increasing refrigerant pressure
D. The evaporator coil picking up heat
Answer: A
11. What safety device protects a compressor from excessive current?
A. High-pressure switch
B. Low-pressure switch
C. Overload protector
D. Thermostat
Answer: C
12. In a refrigeration system, heat is absorbed in the:
A. Condenser
B. Compressor
C. Evaporator
D. Receiver
Answer: C
13. What is the normal operating superheat range for a commercial refrigeration
system?
A. 2-5°F
B. 8-12°F
C. 15-20°F
D. 25-30°F
CONDITIONING TECHNICIANS, 4TH EDITION BY
DICK WIRZ TEST BANK | CHAPTER-BY-CHAPTER
PRACTICE QUESTIONS & ANSWERS | HVAC EXAM
PREP | INSTRUCTOR RESOURCE | STUDY GUIDE PDF
SECTION 1: FUNDAMENTALS OF COMMERCIAL REFRIGERATION
Questions 1-20
1. What component in a refrigeration system removes heat from the refrigerated
space?
A. Condenser
B. Evaporator
C. Compressor
D. Receiver
Answer: B
2. The purpose of the compressor in a refrigeration system is to:
A. Absorb heat
B. Increase refrigerant pressure
C. Expand refrigerant
D. Filter the air
Answer: B
3. Which of the following is a common refrigerant used in commercial systems?
A. R-22
, B. R-410A
C. R-744 (CO₂)
D. All of the above
Answer: D
4. In a refrigeration cycle, the condenser's main function is to:
A. Lower refrigerant pressure
B. Reject heat to the surroundings
C. Store liquid refrigerant
D. Increase humidity
Answer: B
5. A thermostatic expansion valve (TXV) is used to:
A. Control refrigerant flow into the evaporator
B. Filter liquid refrigerant
C. Compress refrigerant
D. Absorb heat
Answer: A
6. What is "superheat" in refrigeration?
A. Temperature of refrigerant below saturation
B. Temperature above saturation at evaporator outlet
C. Pressure difference in compressor
D. Condenser fan speed
Answer: B
7. What tool is typically used to measure system pressures in a commercial
refrigeration unit?
A. Multimeter
B. Refrigeration gauges (manifold)
C. Thermocouple
D. Tachometer
Answer: B
8. Which of the following indicates a possible low refrigerant charge?
A. High suction pressure
B. Low superheat
, C. Frost on evaporator coil
D. Compressor overheating
Answer: C
9. A receiver in a refrigeration system is used to:
A. Store liquid refrigerant
B. Filter moisture
C. Pump refrigerant
D. Measure temperature
Answer: A
10. The term "subcooling" refers to:
A. Cooling of refrigerant below its boiling point
B. Heating of the compressor discharge line
C. Increasing refrigerant pressure
D. The evaporator coil picking up heat
Answer: A
11. What safety device protects a compressor from excessive current?
A. High-pressure switch
B. Low-pressure switch
C. Overload protector
D. Thermostat
Answer: C
12. In a refrigeration system, heat is absorbed in the:
A. Condenser
B. Compressor
C. Evaporator
D. Receiver
Answer: C
13. What is the normal operating superheat range for a commercial refrigeration
system?
A. 2-5°F
B. 8-12°F
C. 15-20°F
D. 25-30°F
