The FL fault code means that the drain pan needs to be emptied. Normally, it does not need to be drained, and it holds a minimal amount of water.
The drain pan may be overfilled if an AC has been operating in cool mode, and there is a high humidity level. If that is the case, it is recommended to slow down the fan and thus reduce air circulation in the room.
Also, the problem may occur if not all doors and windows are closed. It is absolutely imperative that all doors and windows be closed when an AC is working.
If you slow down the fan, the AC will be extracting less moisture from the air. Consequently, you will have to drain the pan less frequently.
If you use the dry mode, removing moisture from the room will be your AC’s main function. This will cause the drain pan to fill more rapidly and you having to empty it frequently. Use cool mode instead of dry mode.
To empty the pan, unplug the drain outlet and tilt it back until all water flows out.