It is possible that the shut-off valve was blocked by the cumulated white stuff. As a result, water supply can not be stopped even when water level is high. , T- V, [/ z5 A& ^3 i F+ z! m* K4 ^" x6 h
Solution: turn off water supply and take the humidifier apart and clean it will stop the leaking. & U5 o' {' W, F! _& _+ T; V ! f- q# E) f" g1 z0 @" O5 a- S ' k) E+ T L& T! N" K! nOtherwise, find a professional or change a new set.