hello,

I am trying to understand how equest interprets outdoor air. I generally
place OA as a system command under the "Minimum outdoor air ratio" box and
leave all zone commands empty. When I put minimum OA to zero and simulate,
I get a warning in the detailed report telling me this. If I then add a min
OA schedule with values of 0.1 for operating hours, I still get the zero OA
warning in the detailed reports, but the energy for space cooling, heating,
etc... goes up as you would expect with the need to condition OA. In
addition, energy for the vent fans does not change very much. Can someone
shed some light as to how equest handles this? I think what I am wanting to
know is if by reducing the OA, is equest resizing the OA fan and is its
energy use taken into account.

Also, is there any place to actually specify the size of an outdoor air fan?
I model mainly existing buildings and think it would be nice to actually
specify what the equipment size is.

I have attached representative files for reference

Marcus Eliason, EIT, LEED AP