Installed aprilaire system. Cut in unit and bypass. Cut in and wired control. Wired up unit to furnace terminal strip. Wired outdoor sensor, piped water to unit. Ran drain line. Cycled system. Operating normal at this time. First year furnace clean and tune. Cycled system. Checked heat exchanger. Checked and cleaned burners and flame sensor. Checked igniter, ok. Checked and adjusted gas pressures to maximize efficiency. Checked for XS air and CO in exhaust, normal levels found. No CO in airstream. System operating normal at this time. Installed 16x25x1 electronic air cleaner. Job complete.