DCM1 complete; AC; (2)F20201 replaced. System is fully functional. All components are operating within design tolerances. Refrigerant pressures and temperatures are appropriate for indoor and outdoor conditions. Put tape around inside of filter grille where cover contacts ( metal to metal ) to try to prevent the rattle. Probable cause of the stained tile is the roof seal at the curb has dry rotted and cracked and is allowing rain water to penetrate to the ceiling tile.