Performed one system heater maintenance on American standard. Upon my name is I came across a few points of concerns regarding air filtration. 1. Found the electrostatic air cleaner Is in need of replacement and catalyst. These are typically swapped out every 3 to 4 years 2. Hi amounts of dirt buildup due to filter not working properly Need to follow up with American standard about electro static air cleaner kit And confirm pricing with Shirley