Upon arrival filters are clean, stat is downstairs on main floor and indoor unit is in attic. Went to attic, blower and coil are clean, no cracks in heat exchanger, cleaned flame sensor. Wires are tight and gas pressure is spot on. Started checking system and found dampers for each vent where closed in the attic. Opened the ones for downstairs and kept upstairs slightly closed. Went down and spoke with the customer and explained what I had found and how the system looks.