Which component should be replaced if a refrigeration system is opened for service?

• A. Orifice
• B. Filter drier
• C. Condenser fan
• D. Oil separator

Answer: (B)

Moisture control is the safety net when a refrigeration system is opened for service. The filter drier is filled with desiccant that removes moisture and traps contaminants from the refrigerant. When the system is opened, air and moisture can enter, and the dried condition is lost, so replacing the filter drier helps prevent water-related problems like acid formation, corrosion, and ice formation in the metering device or lines. After installing a new drier, the system should be evacuated and then recharged to ensure all moisture is removed and the refrigerant remains clean.

The other components aren’t routinely replaced just because the system was opened. The orifice is a fixed metering device, the condenser fan is a motorized cooling component, and the oil separator serves oil management; none are general consumables required solely due to service access.