Arrived to do a performance maintenance. Started maintenance with the basement system. Set up for combustion analysis temperature split and static pressure tests. 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. Checked systems heat exchanger to ensure proper venting of flue gas. Performed an electronic gas leak search. Verified operation of the humidifier. Found that the humidifier panel is coated in calcium and is leaking. Moved inspection to the attic system. Verified temperature split. Checked inside the system for cleanliness. Found that the evaporator coil is impacted with debris and the blower wheel is coated in dust debris. Each of these will impede airflow. Verified operation of heat strips. Measured the systems static pressure. Furnace and air handler are operational at this time.