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. $ c1 Q+ ]4 T+ X3 E" k! B
- x% u; S( z& D2 Y& C" bSolution: turn off water supply and take the humidifier apart and clean it will stop the leaking.; @8 D$ \$ J; {; g. E* b7 v) V
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Otherwise, find a professional or change a new set.