Furnace clean and tune. Cycled system. Checked heat exchanger, ok. Checked, removed , and cleaned burners and flame sensor. Checked and tightened electrical connections and clamps. Cleared drain line. Checked and adjusted gas pressures to maximize efficiency. Preformed combustion test and found normal levels in exhaust. No CO found in airstream. Installed new electronic air cleaner. Cycled and working normal. Instructed customer on use of electronic filter. System operating normal at this time. Ac clean and tune in spring. Job complete. Ac in spring, electronic air cleaner installed 16x25x1