Manual air dryers are used to remove water vapor from compressed air systems, in applications such as paint spraying, laboratory instruments and small control air systems. Filtration for absorber type dryers is important to protect the desiccant bed from contamination. Cleaner incoming air will result in better performance, longer life and fewer service problems. To regenerate silica gel desiccant, it must be heated to at least 350DegF for approximately 3 hr or until color has changed from pink to blue. Allow desiccant to cool to room temperature before pouring back into unit bowl. An after-filter should be placed downstream from the desiccant dryer to ensure solid contaminants such as desiccant dust do not migrate downstream.