DUCT CLEANING - 1st Fl System - Removed all return grilled & supply registers, sprayed and chemically cleaned each vent. Also sprayed and cleaned registers and housing. Vacuumed each supply registers and also cleaned work area on first level and basement level. Had to move furniture to access some vents in home. Removed dirt and debris from ductwork, removed damper and cleaned interior of supply ductwork, sanitized system and hand cleaned each vent. Replaced both air filters for attic & basement unit. Air duct agitation and source removal with high performance HEPA vacuum technology of each supply air trunk duct (primary air ducts). Only where ducts and/or vents are fully accessible. Air duct agitation and source removal with high performance HEPA vacuum technology of each supply air branch (secondary air ducts). Only where ducts and/or vents are fully accessible. Air duct agitation and source removal with high performance HEPA vacuum technology of each return air trunk duct (primary a