To clean refrigerant by the use of filter dryers is called ____.

The process of cleaning refrigerant using filter dryers is referred to as recycling. Recycling entails removing contaminants and moisture from the refrigerant to restore its quality so it can be reused in the system without introducing harmful impurities. This is essential in maintaining the efficiency and longevity of air conditioning and refrigeration systems.

During the recycling process, the refrigerant is processed to eliminate any impurities, which often includes passing it through filter dryers that absorb moisture and filter out particulates. This differs from other processes such as recovery, which involves the removal of refrigerant from the system but does not necessarily clean it, and reclaim, which refers to the process of purifying refrigerant to a specific standard set forth by regulations. Renew is not a commonly used term in this context and does not specifically address the purification of refrigerants. Recycling is the most accurate term for the cleaning process described in the question.