I preformed 2 AC tune ups today. The basement unit is from 2003 and in rough condition. The furnace is very rusted on the inside, this brings concern for potential cracks in heat exchangers and weak spots. I recommended replacing the whole system. The customer said they are waiting to do it through home warranty. The attic unit is in good shape the blower wheel is dirty and potentially the coil. ( coil was inaccessible). The static was high but still in average range. The cap in the condenser was bad, i replaced it and added a hard start to prevent further damage. Both ACs where running when i left.