What is the function of a filter drier in a refrigeration system?

The function of a filter drier in a refrigeration system is to prevent moisture and contaminants from entering the system. Moisture can lead to the formation of ice and other harmful substances that can impair the efficiency and operation of the refrigeration system. Filter driers contain desiccant materials that absorb moisture, ensuring that the refrigerant remains free from water and contaminants. This maintenance of cleanliness and dryness is crucial for the longevity and reliable performance of the system, as contaminants can cause blockages and corrosion, leading to costly repairs and reduced efficiency.

While the other answers might relate to certain aspects of refrigeration system performance, they do not accurately describe the primary role of a filter drier. For instance, maintaining pressure is typically managed by other components such as compressors and expansion devices, and increasing the refrigerant charge is not a function of the filter drier. Controlling refrigerant temperature is also not the primary role; rather, it is managed through the components involved in the refrigerant cycle. Thus, the primary function of the filter drier as a protector of the system from moisture and debris is critical to ensure efficient and uninterrupted operation.