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<p class="MsoNormal"><span style="color:#1F497D">Hi Fred,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I dove into this topic some time back specifically trying to understand the Appendix G curve in relation to reset strategies and the DOE2/eQuest default library curves.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Attached discussion (and attached discussions therein) recounts a lively discussion and some helpful visuals I produced to establish my observations, concluding the App. G curve is ultimately… not clear on the
matter (and thus inappropriate for direct use in evaluating reset vfd control strategies). You may find this an interesting read from the bottom up.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Hope that saves you a few steps!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><br>
~Nick<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D"><img width="119" height="37" id="Picture_x0020_1" src="cid:image001.jpg@01CF32EE.79DD5F70" alt="cid:489575314@22072009-0ABB"></span><b><span style="font-family:"Stylus BT","sans-serif";color:#2D4D5E"><o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-family:"Stylus BT","sans-serif";color:#2D4D5E"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E">NICK CATON, P.E.<o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900">SENIOR ENGINEER<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">Smith & Boucher Engineers</span><span style="font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">25501 west valley parkway, suite 200<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">olathe, ks 66061<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">direct 913.344.0036<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">fax 913.345.0617<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><a href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span style="font-size:10.0pt">www.smithboucher.com</span></a></span><u><span style="font-size:10.0pt;color:blue">
</span></u><span style="color:#1F497D"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> bldg-sim-bounces@lists.onebuilding.org [mailto:bldg-sim-bounces@lists.onebuilding.org]
<b>On Behalf Of </b>Porter, Fred AEC<br>
<b>Sent:</b> Wednesday, February 26, 2014 11:41 AM<br>
<b>To:</b> bldg-sim@lists. onebuilding. org (bldg-sim@lists.onebuilding.org)<br>
<b>Subject:</b> [Bldg-sim] ASHRAE App G VAV Fan Curve<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">All,<o:p></o:p></p>
<p class="MsoNormal">Does anyone know, particularly through having claims accepted by GBCI, whether the ASHRAE App G VAV fan curve is supposed to represent a fan system with or without static pressure reset. I always thought it was supposed to represent a system
with sp reset, conforming to 6.5.3.2.3. However, most of the curve power values are even higher than curves representing VAV/VFD systems without sp reset. A confusing aspect is that compared to other VFD fan curves, the power values are high at high flows,
but low at low flows, even going to zero at zero flow, though that is really meaningless.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As an aside, the 2013 Title 24 ACM now defines fan curves for central VAV systems with and without sp reset, taken from Taylor’s VAV design guide. SP reset is the “baseline” or “standard.”A<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks for any experience or thoughts on this.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Fred<o:p></o:p></p>
<p class="MsoNormal"><b><span style="color:black">Fred Porter, BEMP, LEED</span><span style="color:#1F497D">©</span><span style="color:black"> AP<o:p></o:p></span></b></p>
<p class="MsoNormal" style="margin-bottom:2.0pt"><span style="color:#7F7F7F">Senior Energy Analyst<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="color:#005DAA">Architectural Energy Corporation<o:p></o:p></span></b></p>
<p class="MsoNormal"><i><span style="font-size:9.0pt;color:#005DAA">A Member of NORESCO Energy and Sustainability Services<o:p></o:p></span></i></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#7F7F7F">2540 Frontier Ave, Suite 100, Boulder, CO 80301<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#7F7F7F">Phone 303.459.7425 |
<a href="mailto:fporter@archenergy.com">fporter@archenergy.com</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#807F83"><a href="http://www.archenergy.com">www.archenergy.com</a></span><span style="font-size:9.0pt;color:#807F83"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;color:#7F7F7F"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><o:p> </o:p></p>
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