When "FC" flashes on the display screen of the Kelon air conditioner indoor unit, it indicates that the machine is executing the "filter cleaning prompt function" and prompts that the filter needs to be cleaned. Some products are displaying "FC" At the same time, there will also be a beeping sound, and the above phenomenon should be explained to the user. 1. FC reminds the air conditioner that the filter should be cleaned. This is a personalized reminder function. This is a code of Kelon air conditioner; when the fan in the air conditioner has been running for 200 hours, it will enter the filter cleaning prompt state and the FC prompt will be displayed. 2. It is important to keep the filter clean at all times. Without the prompt function, people will continue to use it in a harmful state. After cleaning the filter, just press the reset switch (emergency). If you are not sure, please read the air conditioner manual. 3. By pressing the button on the remote control (continue to hold the high efficiency button for 5 seconds, the remote control will send a cleaning reset code), the filter cleaning reset can be completed; (This plan is a universal plan) 4. Through the "emergency button" on the indoor controller The operation can complete the filter cleaning and reset; in the cleaning prompt state, press the "emergency button" once to reset and cancel the cleaning prompt, and the emergency button will resume its function. (If the controller is designed with a dedicated cleaning reset button, the cleaning reset button will be used first.) 5. After exiting the cleaning prompt state, the air conditioner returns to normal display and operation, and the fan cumulative timer is cleared. FC is displayed. This is Kelon's patented technology - the display of dust mites on the filter. It prompts you to clean the filter. After cleaning, the word FC will disappear! If it is not cleaned in time, the word FC will appear every time it is turned on!