Aircon water leakage on the indoor unit can occur due to various reasons such as clogged drain pipes, dirty filters, or low refrigerant levels. If you notice water dripping from your aircon unit, turn it off immediately and contact a professional aircon service provider to diagnose and fix the issue. To stop the aircon water leakage, the technician will typically clean the aircon filters and evaporator coils, clear the drain pipes, and check the refrigerant levels. Regular aircon service and maintenance can prevent this issue from occurring in the first place.