Cleaned and flushed the drain line. Checked the amp draw on the: blower 3.12 max 6; heat strip 0; condenser fan 1.15 max 1.3; compressor 9.88 max 21.8; static pressures .34 supply and .2 supply; temperature split 67.2/51.6. Cleaned and washed the filter. Rinsed out the condensing coil. The evaporator coil is rusting and will eventually cause it to leak. The ductwork is original to the home and is a mixture of grey duct and ductboard trunk lines. The insulation in the attic is the old cellulose and has compressed well below the efficacy. Recommend having a senior tech come out to give an estimate on replacing the system, ductwork, and having insulation blown in.