DW and I are shopping for a new HVAC system (proactively) for the upstairs, which is about 1200sqft. Current HVAC is a 80%, 10-SEER TRANE split system. Furnace and air handler in the attic, A/C unit outside. We live in Cary, NC, home was built in 1998, and has the original HVAC system
My DW...