CFESA Refrigeration Systems 1 — Questions and Answers
Question 1: What is the primary refrigerant used in most modern commercial food equipment refrigeration systems?
- R-22
- R-404A (Correct answer)
- R-134a
- R-410A
Correct answer: R-404A
R-404A is widely used in commercial food refrigeration due to its compatibility with medium and low temperature applications.
Question 2: Which component in a refrigeration system is responsible for removing heat from the refrigerant?
- Evaporator
- Compressor
- Condenser (Correct answer)
- Expansion valve
Correct answer: Condenser
The condenser releases heat absorbed by the refrigerant to the surrounding environment, completing the refrigeration cycle.
Question 3: What does superheat indicate in a refrigeration system?
- Temperature of the condenser coil
- Temperature rise of vapor above its saturation point (Correct answer)
- Subcooling at the liquid line
- Discharge temperature at the compressor
Correct answer: Temperature rise of vapor above its saturation point
Superheat is the number of degrees the refrigerant vapor is above the boiling point at a given pressure, ensuring no liquid enters the compressor.
Question 4: A technician measures a high head pressure and normal suction pressure in a walk-in cooler. The most likely cause is:
- Low refrigerant charge
- Dirty condenser coils (Correct answer)
- Stuck open TXV
- Faulty evaporator fan
Correct answer: Dirty condenser coils
Dirty condenser coils restrict airflow and heat transfer, causing head pressure to rise above normal operating range.
Question 5: What is the purpose of a receiver in a commercial refrigeration system?
- Store extra refrigerant and ensure liquid feed to the expansion device (Correct answer)
- Filter moisture from the refrigerant
- Separate oil from the refrigerant
- Measure refrigerant flow rate
Correct answer: Store extra refrigerant and ensure liquid feed to the expansion device
The receiver stores liquid refrigerant to accommodate system load variations and ensures a steady liquid supply to the expansion device.
Question 6: When recovering refrigerant from commercial equipment, technicians must comply with which EPA regulation?
- Section 608 of the Clean Air Act (Correct answer)
- Section 404 of the Safe Drinking Water Act
- Title V of the Clean Water Act
- OSHA 29 CFR 1910.119
Correct answer: Section 608 of the Clean Air Act
EPA Section 608 requires technicians to recover refrigerants using certified equipment and prohibits intentional venting of regulated refrigerants.
CFESA Refrigeration Systems 1
What is the primary refrigerant used in most modern commercial food equipment refrigeration systems?