Return ducts were not connected to hvac ducts, registers and covers on the walls. Wall cavity filled with insulation used as a return.
Beams blocking return, The floor joists were used as a return in basement(NO sheet metal was used when a supply duct was over it. You could just reach right up. Had a special air blower installed to add air to basement to try to correct negative air pull. Helps if you cover the floor joists,or connect wall registers to the return duct.
Total amateur hour. I had a really bad door slam when system was running to basement. No quality control. Pilot light to water heater would go out, gee i wounder why?
Pulled air from chimney to make up for negative air pulled from basement. They are idiots.
Reason of review: Bad quality.