Arrived to do a performance maintenance. Set up for combustion analysis temperature split and static pressure tests. Found that the system is operating just above the maximum rated static pressure. Verified operation of all mechanical and electronic components of the furnace. Checked blower for cleanliness and to see if there is any play in the bearings. Found that the fan for heating and cooling is beginning to collect dust. Considering how new the system is and how dirty the fan is, began checking ductwork for cleanliness. Found that the return ductwork has a heavy coating of dust and clumps of dust. Checked systems heat exchanger to ensure proper venting of flue gas. Furnace is operational at this time.