AC tune up refer to health inspection report form. Filter is dirty should be replaced in the next month or so given current condition. 1†filters need replacement after about a month or two of use ideally to keep everything running smoothly and appropriately. There is a thin layer of dust on inside of of blower motor compartment and on the evaporator coil. Main reason for this is these fine particles of dust are able to make it through the filter in use the way we can fix this is using a higher rated filter at the sacrifice of airflow, which is not recommended because this will have a negative effect on efficiencies of AC and Furnace use. The other and more practical way is by adding an Air Purifier. An Air Purifier in effect ionizes these small particles where they become attracted to one another and clump up and are then able to be caught by the filter because of their larger size. And will aid and benefit respiratory health of homes air quality by helping eliminate pollutants tha