2 furnace pm check complete. Did not change main level filter. Main level mechanical and electrical components in good shape. Main level furnace has good combustion readings. Main level flue pipe is no longer up to code, it is single wall and should be double wall. Did not change upstairs filter. Upstairs furnace has worn ignition system with silica dust build up, recommend changing next year. Dusted out furnace cabinets. Insulation levels are low, recommend adding more insulation. Systems heating at this time.