4 systems total. 3 systems in main home. Customer states that there is an abnormal amount of dust accumulating in the home. Upon further inspection, the technician has discovered mild dust build up starting to form on all 3 blower wheels and evaporator coils. There seems to be some air bypassing the box filters due to the construction of the filters and boxes. No apparent leaks in the duct work. Suggest a duct cleaning and a filter upgrade to prevent further buildup. Attic insulation level is currently at an R38. Main system does not have any drain protection. Filter boxes are as follows Upstairs system : 28x17 Main system : 28x21 East side system : 28x20