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. ' H* ]& u% C1 u9 x7 \8 ? 3 M! s1 H! D9 GSolution: turn off water supply and take the humidifier apart and clean it will stop the leaking. 8 u$ f$ I1 j& o. U* c9 E; Z( C t X" g/ ~1 A5 m' Z
8 G+ d& t% o6 B4 N) C$ {4 V4 cOtherwise, find a professional or change a new set.