Arrived to do a performance maintenance. Set system for cooling. Measured the systems static pressure measured a temperature split between return and supply air. Found that the system is operating well beyond the manufacturer specifications on static pressure. Reached out to a field supervisor to finish the diagnosis on the systems static pressure. Checked interior of the furnace for cleanliness. Found that the blower wheel is heavily coated in dust debris and bacterial growth is present on the evaporator pan. Went outside and verified refrigerant levels. Verified operation of all electronic and mechanical components. Rinsed coil free of debris. Spoke with homeowner about the system. Air conditioning system is operational at this time.