If a building less than 3 floors has an air handler that serves multiple
spaces with a capacity of X for the proposed model, then it will require an
hvac system type packaged single zone.

Would it be correct then to provide a PSZ for each zone modeled? If so how
should the capacities in the baseline be broken up? Take the proposed
capacity and proportion it for each zone based on size, loads, etc.. Then
multiply capacities by 1.15 and 1.25 to get a baseline capacity for each
system? This doesn't account for supply air volumes.

Or how about a residential high rise? The baseline hvac system type would
be PTAC's. Consider that each building wing is modeled as a large zone (
not a zone for every room ). When a PTAC was made to serve this large zone
it did not do so well but I did not take much time investigating because I
did not want to waste time on it. If the parameters are set correctly, a
PTAC can be able to condition a zone no matter the size?

Has anyone had these questions before? The archives and user's manual do
not provide much insight.

Kevin Kyte, LEED AP