Hi XXXXX,
Try the following in order as printed here.
Turn the power by pressing the power button.
Disconnect the air conditioner cord from the wall.Hold the power button down and plug the cord back in.
Keep holding the power button down until it runs through a test sequence and you hear an audible beep that means it has completed its test mode.
Now the machine will be off,
Disconnect the cord one more time, then wait fifteen seconds and plug it back in. Then start the unit up. That should clear the filter alarm code.
Thanks
Mark
Journeyman Technician
UA Journeyman Pipefitter , HVAC, Refrigeration, DDC controls. 26 years.Commercial & residential