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<p><font size="2" color="#800080">Robby,</font><br>
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<font size="2" color="#800080">You are correct when you say the system must provide ventilation air while occupied - that is a requirement in every mechanical code I've read - I haven't read the codes from the 70's when sick-building-syndrom (SBS) was rampant, at that time ventilation was cut down in systems, and energy was saved, but SBS was created. </font><br>
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<font size="2" color="#800080">"</font><font color="#1F497D" face="Calibri"> If that’s the case then the fans would never turn off during occupied hours and then would cycle with the load during unoccupied hours. </font><font size="2" color="#800080">"</font><br>
<font size="2" color="#800080">The above statement is exactly correct and how it should be modeled.</font><br>
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<font size="2" color="#800080">You would be modeling a heating system in the proposed building. It would be whatever is really used (like the cabinet unit heaters). </font><br>
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<font size="2" color="#800080">The baseline and proposed buildings don't have to have the same fan system, however your baseline fan system is determined by tables G3.1.1A and G3.1.1B. Once you determine your system type from G3.1.1A go to table G3.1.1B and look at what your system is comprised of, it will give you system type, fan type, cooling type and heating type. Your baseline is set in stone by ASHRAE.</font><br>
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