DCM1 complete; Heat; (2) F20201 replaced. System is faulting on high limit. Identified 90° return air at the grill. The high temp limit switch is designed to open at 100°. Recommend installing a fresh air intake that can offset the high air temperature found on the ceiling. System is maintaining temperature in the condition space
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.