Arrived to do performance maintenance. Inspected the condensation drain line for flow. Inspected system air filter and replaced it with homeowners supplied filter. Verified operation of all mechanical and electronic components in the furnace. Checked blower for cleanliness and to see if there is any play in the bearings. Checked system heat exchanger to ensure proper venting of flue gas. Checked air conditioning coil for cleanliness and to see if there are any restrictions to airflow. Found that there is bacterial growth starting on the underside of the condensation pan. Analyzed the combustion gas to ensure safe and efficient flame. Performed an electronic gas leak search. Furnace is operating properly at this time. View visual findings from this job here - https://visionshare.xoi.io/?id=XA-4E40-1802EBA6CC454CE084769A5C320E442E