■ Reason: When dust or contaminant accumulates on the inside filter in the rooms, the check light is on the filter letter.
■ How to manage the Inside filter: The inside filter and the tray of each rooms, please clean them every 2~3 months for best performance.

If it is difficult to periodically clean the inside filter, it is recommended to replace it when the filter check light comes on.

If the model you are using is not a KS series, you can call our Customer Service Center when the Filter check light is on.