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. ; S! C0 f$ l' T( h# I" _( L* v+ S- w
Solution: turn off water supply and take the humidifier apart and clean it will stop the leaking.* x# ~2 ]$ F/ D2 _, b6 e% T/ I5 @) u
5 V0 T; b2 C3 T# Y
1 e5 Z2 h( J P' q8 T( rOtherwise, find a professional or change a new set.