Found Mitsubishi unit in living room to be packed with dirt on the blower wheel found back bedroom on left to have some dirt on it but not packed with dirt where it’s falling off like what’s in the living room room. The blower wheel should be pulled and cleaned. top floor should be pulled and clean in a couple years. It’s not that bad. We pulled and cleaned the indoor blower wheel cleaned the unit and got rid of all the biological growth in. It started everything up and tested. It works fine. Looks good pictures included.