On this project Duct & Vent Cleaning of America, Inc. used a contact HEPA vacuumed and washed coils in three air handling units. We contact HEPA vacuumed the supply and return ductwork in areas with drop ceilings. Inaccessible ductwork above the sheet rock ceiling in the sanctuary was cleaned by putting the ductwork under negative pressure with a high volume negative air machine while utilizing rotary brush cleaning techniques to dislodge built up debris.
