Inside of air handler cabinet Dust and debris has built up on scroll wheel and walls. This is due to the washable filter on the downstairs return washable filters only filter out about 10% of those particles. Downstairs system (TRANE) 1. Air scrubber plus ionizes entire house along with disinfecting all surfaces with hydrogen peroxide in airstream. Reduces all dust buildup 2. 5 inch thick Merv 11 cabinet To stop 90% of dust particles on high efficiency filter (6-12 month lifespan of filter) 3. Blower wheel cleaning by removing indoor blower’s and spraying down scroll wheel outside with Safe chemical cleaner.