I am trying to model a baseline building of which I specified a packaged
single zone DX furnace system per zone auto size.

The Model results in well over the allowed ASHRAE 90.1-2004 unmet hours
(300hrs) when I total the number of unmet hours for each space. What I
have been doing is incrementally increasing the sizing ratio for each
space until the system is within the unmet cooling / heating hours
respectively.

What I would like to know, is there a better way to reduce the number of
unmet hours without having to manually enter in the sizing ratio? What
has everyone been doing to reduce the number of unmet hours for systems
that are auto sized?

Thank you in advance for any suggestions.

David Dowling