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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>I am modeling a school gymnasium building that has two gyms and a two
story office/locker room wing. The office/locker room wing has several
zones that have very different loads, but are designed to all be served by the
same packaged, constant volume, 100% outside air ERV. In the design case
model, heating is supplied to these zones primarily by HW baseboards, while
cooling loads are satisfied by the supply air.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Appendix G dictates that the baseline HVAC system be Type 3, PSZ-AC
with constant volume DX cooling and furnace heating (no reheat). When
modeling this system type, I am getting a large amount of unmet heating and
cooling hours (as many as 1,500 hours for a given zone) in the office/locker
room zones. My guess is that this is happening because the baseline HVAC
system has no heat source at the zone level (where the proposed case has
baseboards), and many of the slave zones have very different heating/cooling
loads than the control zone. I am not sure how I can adjust the model to
eliminate these unmet hours while still being consistent with Appendix G.
The only method that has worked for me so far is to drastically increase the system
supply flow, but this creates large fan savings that may not be reasonable.
Is it appropriate to add zone reheat even though it is not called for in
Appendix G? <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Hopefully I’ve presented my problem clearly enough. Any
help would be much appreciated!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Rob Bialobrzeski<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>DMI<o:p></o:p></span></font></p>
<p class=MsoNormal><st1:Street w:st="on"><st1:address w:st="on"><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>35 Walnut Street</span></font></st1:address></st1:Street><o:p></o:p></p>
<p class=MsoNormal><st1:place w:st="on"><st1:City w:st="on"><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>Wellesley</span></font></st1:City>,
<st1:State w:st="on">MA</st1:State> <st1:PostalCode w:st="on">02481</st1:PostalCode></st1:place><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Phone: 781-431-1100 x17<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Fax: 781-431-1109</span><o:p></o:p></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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