Pkg clean and tune . Furnace. Cycled system. Checked heat exchanger. Found all three chambers are rusted and corroded. Ignition system is worn. Unable to remove burners to clean due to extremely heavy rusting around screws. Found that ventor motor bearings are worn. Found burner compartment and burner box cover extremely rusted and damaged. Cleared drain lines. Lines are very corroded. Checked XS air and CO levels. Normal levels found. No CO found in airstream. Average life of this unit is 14 years. This system is 30+ years old and in poor condition. Future failure is expected. Ac. Checked indoor coil with refrigerant sniffer. No major indications of leak found. Checked filter. Checked and cleaned electrical compartment. Found contactor and capacitor worn. Tested compressor and fan motor. Both tested low, but just in normal range. Used coil cleaner on condenser coil. Hooked up gauges and checked pressures and temps. Found subcooling was 29, super heat was 8. Temp split was 14. Sys