Originally Posted by
motoguy128
I disagree. A below grade basement without a lot of windows, that's not occupied, will acutally have a negative heat load. In a zoned system, I'd even treat it as a heat sink. It will rarely if ever be calling for cooling unless you're entertaining.
IF well insulation, 2000 sqft townhome in that climate might only really need 2-2/12 tons. 3 will be plenty and even if the load cal says 3.2 or 3.5 tons, with a zone system, you can undersize.
A 95F day is 6-7F above design temprature there. where you might need 3.5-4 tons for Missouri, Texas or Florida, you'd only need 3 tons in Queens.
Plus on zoning, oversizeing causes problems, because now you need even larger ducts and more supplies for the smallest zone. Infinity, helps with this by modulating, but you can still find that other zones are over conditioned. Of course a proper Manual D and room by room load calculation will eliminate all of these problems.