Got a leaking AC coil that is just starting to rust the furnace portion. It's a 1992 York using the old refrigerant. Got a quote for a Goodman 80% efficiency (AC/Furnace/Compressor) but thinking maybe I should just replace the coil /save the money/and see how much longer I can go. The furnace and compressor seems to be in otherwise good shape except for the AC leaking. Advice or suggestions appreciated! Any other ideas? Plan to move in 5 years so I could lower the house price figuring that the AC coil was replaced but other units 15 years old.