Bought a 1928 colonial about 6 months ago where the prior owners had installed in 1980 an HVAC in a weird configuration. It was installed in the attic and they have the flexible ducts running through the closets and into the ceilings of the first floor (foyer, living room, dining room, kitchen) and 2nd floor (3 bedrooms, den) and 2 ducts in the finished part of the attic where the flexible ducts run behind the drywall. The return duct is actually in the attic they just punched a hole in the closet where the HVAC is housed and threw a filter in front of it. There are no other return lines. I'm forced to keep the attic door open and the office door (since the attic stairs are in the office) so the return air can flow back through the system.
Any thoughts on how to get around this configuration without a major overhaul?