Complete 3 system furnace repair and preventative maintenance check. Found main and basement unit working good with drain pan switch tied to condensate pump. Switches working properly. Changed filters. Blowers are clean. No signs of growth in systems or ductwork. Both ignition controls all working good and cleaned. Recommend inline float switch to prevent water damage to furnace. Customer declined. Upstairs unit is 20+ years old and has very dirty blower wheel as well as weak capacitor and over stressed induced motor. System also has signs of corrosion on evap coil and definite signs of mold around system. System needs to be replaced as well as having an air purifier installed to cleanse the air and prevent harm to residents.