Per previous AC tune up earlier today, changed 3 10x20x1 pleated filters to go with duct cleaning, also changed dual capacitor for compressor. Unable to clean evaporator coil or blower wheel because of location if furnace, half a wall is blocking from removing components for proper cleaning. Customer will wait and have system changed. Layed drop seers where necessary, shop vacced out heavy sand and construction debris from supplies. Duct cleaned 14 supplies upstairs and downstairs with 3 to 4 passes each. Sealed 2 supplies in NE downstairs kids bedroom that were rusting out and living room supply on north side by main entrance. Duct cleaned returns with 10 passes each, upstairs returns had a 90 degree bend about 15-18 feet in that I could not get past. Vacuumed up excess debris and fogged in hospital grade disinfectant spray. Replaced grills and vents. Found some residual mud in the central part of the ductwork, and some fill sand has come into the plenum under the furnace and evap co