CFESA Refrigeration Systems 4

Question 1

What is the primary purpose of a liquid line filter-drier in a commercial refrigeration system?

Accepted Answer

Remove moisture and contaminants from the refrigerant

Answer

A liquid line filter-drier removes moisture, acid, and solid contaminants from the refrigerant to protect the system components.

Question 2

A technician finds frost forming uniformly across the entire evaporator coil in a walk-in cooler. What is the most likely cause?

Accepted Answer

Restricted airflow across the coil

Answer

Uniform frost across the entire evaporator typically indicates restricted airflow, while low charge usually causes frost only on part of the coil.

Question 3

Which refrigerant property is measured by a superheat reading at the evaporator outlet?

Accepted Answer

The vapor temperature above its saturation point at that pressure

Answer

Superheat is the temperature of refrigerant vapor above its saturation (boiling) temperature at a given pressure, confirming all refrigerant has vaporized.

Question 4

When replacing a hermetic compressor in a commercial reach-in refrigerator, what procedure is MOST critical before brazing the new compressor in place?

Accepted Answer

Recover all refrigerant and pull a deep vacuum

Answer

All refrigerant must be recovered before opening the system, and a deep vacuum must be pulled to remove moisture and non-condensables before recharging.

Question 5

A commercial ice machine produces small, cloudy ice cubes. What is the MOST likely cause?

Accepted Answer

High mineral content in the water supply

Answer

High mineral content (hard water) causes cloudy, small ice cubes because minerals become trapped in the ice matrix as water freezes.

CFESA - Commercial Food Equipment Service Association Practice Test

CFESA - Commercial Food Equipment Service Association Practice Test

CFESA Refrigeration Systems 4