Flame sensor needed to be replaced unit is now operational also performed heating maintenance and recommended customer to start thinking on a new unit since this existing unit is 19 years old and drain pan is rotting out will eventually cause water damage heat exchanger in ok condition and rusting but do recommend changing unit for longer functionality Current unit is 80 % furnace in attic 5 ton unit 2600 sq ft home blown insulation will need to take off staircase to take out old furnace return air is good r22 unit Recommend new line set with line set cover Single story home double pane windows good insulation in attic