Taste change: When the filtering effect of the filter element declines, the taste of the smoke may change, becoming bitter, having a strong peculiar smell, or not being as smooth. At this time, it indicates that the filter element may need to be replaced.
Reduced smoke volume: If a significant reduction in the smoke volume of the e-cigarette is noticed, it may be that the filter element is blocked, affecting the air flow. This is also a signal that the filter element needs to be replaced.
Observe the appearance of the filter element: Some filter elements will obviously change color after being used for a period of time, such as changing from white to yellow or brown. This indicates that the filter element has adsorbed a large amount of harmful substances and may need to be replaced.