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. ( f, A" Q5 B8 O/ x7 q. B r/ A" z6 Z3 M% s
Solution: turn off water supply and take the humidifier apart and clean it will stop the leaking. 7 \7 i! ?# W, S& H* p * C3 j& H% c4 B3 d* V2 \- i" z# _- M2 Z1 \; Z; ~* R$ T5 t
Otherwise, find a professional or change a new set.