wash
浣 centers on washing with water, especially rinsing or cleansing something.
浣 combines 氵 (water) with 完, which likely contributes the sound and the idea of completeness, suggesting thorough washing.
Water 氵 plus 完 (complete) suggests a complete wash: rinsing something thoroughly with water.
For カン, imagine washing a can in the sink: can -> カン, and the water 氵 makes it clean.