Over the winter I had a new Infinity furnace installed in the attic to heat the 2nd floor and finished attic. I wish I would have thought to ask this before the install but I'm now wondering how big a job it would be to make it a "zoned" system, so that the two floors operate on the basis of independent thermostats. The problem is, in order for the family to be comfortable on the second floor (therm set at 69 degrees) I typically have to open the windows to not swelter in my attic office. I closed the one supply to the attic (unscrewed it and put a piece of plastic behind it to really seal it) and it still gets too hot for me. Can I retro-zone the system now or are there other options to equalize the heat?