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. 5 C# _) E& y2 k2 x
! k7 J: e D. n& P( H0 mSolution: turn off water supply and take the humidifier apart and clean it will stop the leaking.) K' I; [) ]# C9 b; L5 m
+ H: ~# F2 z: `+ \; S0 ~& N # P. t y7 k8 w. {( f- l+ uOtherwise, find a professional or change a new set.