<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman,new york,times,serif;font-size:12pt">I received a comment back from a recent LEED submission. The reviewer required that I calculate pfan per G3.1.2.9. I didn't argue since this increased my baseline energy consumption and increased my proposed savings.<br><div> </div>Paul Diglio, CEM, CBCP<br><br><div>87 Fairmont Avenue<br>New Haven, CT 06513<br>203-415-0082</div><br><br><div><span><a target="_blank" href="http://www.pdigliollc.com">www.pdigliollc.com</a></span><div><br></div><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><br><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><font face="Tahoma" size="2"><hr size="1"><b><span style="font-weight: bold;">From:</span></b> Maria Karpman <maria.karpman@karpmanconsulting.net><br><b><span
style="font-weight: bold;">To:</span></b> Nick Caton <ncaton@smithboucher.com>; Paul Riemer <Paul.Riemer@dunhameng.com>; Steve Burley <steve.burley@csa-eng.biz>; equest-users@lists.onebuilding.org<br><b><span style="font-weight: bold;">Sent:</span></b> Thu, May 31, 2012 11:35:41 AM<br><b><span style="font-weight: bold;">Subject:</span></b> Re: [Equest-users] 90.1 App G Fan Power and EER Calculations<br></font><br>
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--></style><div class="WordSection1"><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">Nick, Steve and Paul,</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">I believe that using ARI fan power in EIR calculations is the way to go, because the efficiency tables in 90.1 Section 6 show the required performance at ARI conditions (see the last column in each table), not at the project conditions. Here is the related abstract from 90.1 Section 6:</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal" style=""><b><span style="font-size:10.0pt;">6.4.1.1 Minimum Equipment Efficiencies—Listed</span></b></p><p class="MsoNormal"
style=""><b><span style="font-size:10.0pt;">Equipment—Standard Rating and Operating Conditions.</span></b></p><p class="MsoNormal" style=""><span style="font-size:10.0pt;">Equipment shown in Tables 6.8.1A through 6.8.1G shall have</span></p><p class="MsoNormal" style=""><span style="font-size:10.0pt;">a minimum performance at the specified rating conditions</span></p><p class="MsoNormal"><span style="font-size:10.0pt;">when tested in accordance with the specified test procedure.</span><span style="font-size:11.0pt;font-family:"sans-serif";"></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">When a packaged system that meets 90.1 efficiency requirements at ARI conditions is installed in a project where the fan power is higher than in ARI testing procedure (e.g.
projects with more extensive ductwork, air filters, energy recovery, etc.), it will have a lower actual EER than what’s listed in Section 6. However, this wouldn’t make the installation incompliant with mandatory efficiency requirements in 90.1 Section 6. In my experience, LEED reviewers do comment on EIR calculations if EIR is not what they expect. However, using Appendix G fan power in baseline EIR calculations typically results in a more stringent baseline (lower EIR), so they do not insist on changing it. </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">Thanks,</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">Maria</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in;"><p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"sans-serif";">From:</span></b><span style="font-size:10.0pt;font-family:"sans-serif";"> equest-users-bounces@lists.onebuilding.org [mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Nick Caton<br><b>Sent:</b> Thursday, May 31, 2012 9:56 AM<br><b>To:</b> Paul Riemer; Steve Burley; equest-users@lists.onebuilding.org<br><b>Subject:</b> Re: [Equest-users] 90.1 App G Fan Power and EER Calculations</span></p></div></div><p class="MsoNormal"> </p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">Hi
Paul!</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">I maintained the exact same position for a long while, though I thought I was the vocal minority =)! Ultimately, you can argue for/against either approach as having different advantages of ‘correctness.’ I’ve heard future addenda or versions of 90.1 may address the conundrum by stipulating something more simplistic than either approach, like a uniform “factor” to come up with compressor/condenser energies from the total consumption.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">My final position is both approaches
make sense, and for different reasons – modelers should use whichever they feel most comfortable defending should their methodology come into question. My LEED reviewers have to this point taken zero interest in which approach I’ve used in my calculations, after using both, so I take it this degree of nuance is probably not on their usual checklists. I’ve switched over to the ARI approach for a few reasons, but not because I feel a Pfan-based approach is ‘wrong.’</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">Best wishes,</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">~Nick</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><div><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"><img id="Picture_x0020_1" src="cid:1.3822119412@web83302.mail.sp1.yahoo.com" alt="cid:489575314@22072009-0ABB" height="37" width="119"></span><b><span style="font-size:11.0pt;font-family:"sans-serif";color:#2D4D5E;"></span></b></p><p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"sans-serif";color:#2D4D5E;"> </span></b></p><p class="MsoNormal"><b><span style="font-family:"sans-serif";color:#2D4D5E;">NICK CATON, P.E.</span></b></p><p class="MsoNormal"><span style="font-size:7.5pt;font-family:"sans-serif";color:#CC9900;">SENIOR ENGINEER</span></p><p class="MsoNormal"><span
style="font-size:7.5pt;font-family:"sans-serif";color:#CC9900;"> </span></p><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"sans-serif";color:#2D4D5E;">Smith & Boucher Engineers</span><span style="font-size:7.5pt;color:#CC9900;"></span></p><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"sans-serif";color:#2D4D5E;">25501 west valley parkway, suite 200</span></p><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"sans-serif";color:#2D4D5E;">olathe, ks 66061</span></p><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"sans-serif";color:#2D4D5E;">direct 913.344.0036</span></p><p class="MsoNormal"><span style="font-size:10.0pt;font-family:"sans-serif";color:#2D4D5E;">fax 913.345.0617</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"><a rel="nofollow"
title="blocked::www.smithboucher.com"><span style="font-size:10.0pt;">www.smithboucher.com</span></a></span><u><span style="font-size:10.0pt;font-family:"sans-serif";color:blue;"> </span></u><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"></span></p></div><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in;"><p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"sans-serif";">From:</span></b><span style="font-size:10.0pt;font-family:"sans-serif";"> Paul Riemer <a rel="nofollow" ymailto="mailto:[mailto:Paul.Riemer@dunhameng.com]" target="_blank" href="mailto:[mailto:Paul.Riemer@dunhameng.com]">[mailto:Paul.Riemer@dunhameng.com]</a> <br><b>Sent:</b> Thursday, May 31, 2012 7:29 AM<br><b>To:</b> Nick Caton; Steve Burley; <a
rel="nofollow" ymailto="mailto:equest-users@lists.onebuilding.org" target="_blank" href="mailto:equest-users@lists.onebuilding.org">equest-users@lists.onebuilding.org</a><br><b>Subject:</b> RE: 90.1 App G Fan Power and EER Calculations</span></p></div></div><p class="MsoNormal"> </p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">Nick, Steve, and list,</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">I think I concur more with Steve. If you use Nick’s approach to calculate the cooling EIR by subtracting out ARI rated fan power from the 90.1 EER <u>AND</u> then model the 90.1 fan power limits directly, you will be modeling a packaged unit that does not comply with the package EER. </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;">I could see using other splits of fan
and cooling, but a baseline model should comply with both limits.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><div><p class="MsoNormal" style=""><b><span style="font-size:9.0pt;font-family:"sans-serif";color:#5F574F;">Paul Riemer, PE, LEED AP BD+C</span></b><span style="font-size:9.0pt;font-family:"sans-serif";color:#1F497D;"> </span><span style="font-size:10.0pt;font-family:"sans-serif";color:#5F574F;"></span></p><p class="MsoNormal"><b><span style="font-family:"sans-serif";color:#C00000;">DUNHAM</span></b><span style="font-size:11.0pt;font-family:"sans-serif";color:#C00000;"></span></p></div><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"sans-serif";color:#1F497D;"> </span></p><div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in;"><p
class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"sans-serif";">From:</span></b><span style="font-size:10.0pt;font-family:"sans-serif";"> <a rel="nofollow" ymailto="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank" href="mailto:equest-users-bounces@lists.onebuilding.org">equest-users-bounces@lists.onebuilding.org</a> [<a rel="nofollow" ymailto="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank" href="mailto:equest-users-bounces@lists.onebuilding.org">mailto:equest-users-bounces@lists.onebuilding.org</a>] <b>On Behalf Of </b>Nick Caton<br><b>Sent:</b> Tuesday, May 29, 2012 10:51 AM<br><b>To:</b> Steve Burley; <a rel="nofollow" ymailto="mailto:equest-users@lists.onebuilding.org" target="_blank" href="mailto:equest-users@lists.onebuilding.org">equest-users@lists.onebuilding.org</a><br><b>Subject:</b> Re: [Equest-users] 90.1 App G Fan Power and EER Calculations</span></p></div></div><p
class="MsoNormal"> </p><div><p class="MsoNormal" style="">Steve,</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">There are two schools of thought for dealing with fan power in cooling efficiency calcs. The first pulls away the baseline fan power Pfan, as you’re describing, and the other instead pulls out a fan energy draw based on ARI testing procedures… 400 CFM/ton à 365W/1000CFM. I follow the latter these days, but see both as viable.</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">The two approaches result in similar results when your Pfan calculation doesn’t involve a lot of static pressure adders. When it does, the approaches diverge in a fashion that may be either problematic or helpful in a LEED rating sense. Attached discussion sums up things further, includes an outline of an ARI-based approach. You can find more discussions and read into
advantages/disadvantages to both approaches in the mailing list archives.</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">That said, I haven’t checked your math or references but the procedure you’ve roughly outlined sounds alright for a Pfan approach. There are steps in between what you’ve written for correctly coming up with Pfan, but I take it that’s implicit.</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">~Nick</p><div><p class="MsoNormal" style=""><img id="_x0000_i1026" src="cid:1.3822119412@web83302.mail.sp1.yahoo.com" alt="cid:489575314@22072009-0ABB" height="37" width="119" border="0"><b></b></p><p class="MsoNormal" style=""><b> </b></p><p class="MsoNormal" style=""><b>NICK CATON, P.E.</b></p><p class="MsoNormal" style="">SENIOR ENGINEER</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">Smith & Boucher Engineers</p><p class="MsoNormal"
style="">25501 west valley parkway, suite 200</p><p class="MsoNormal" style="">olathe, ks 66061</p><p class="MsoNormal" style="">direct 913.344.0036</p><p class="MsoNormal" style="">fax 913.345.0617</p><p class="MsoNormal" style=""><a rel="nofollow">www.smithboucher.com</a><u> </u></p></div><p class="MsoNormal" style=""> </p><div><div><p class="MsoNormal" style=""><b>From:</b> <a rel="nofollow" ymailto="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank" href="mailto:equest-users-bounces@lists.onebuilding.org">equest-users-bounces@lists.onebuilding.org</a> [<a rel="nofollow" ymailto="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank" href="mailto:equest-users-bounces@lists.onebuilding.org">mailto:equest-users-bounces@lists.onebuilding.org</a>] <b>On Behalf Of </b>Steve Burley<br><b>Sent:</b> Tuesday, May 29, 2012 6:37 AM<br><b>To:</b> <a rel="nofollow" ymailto="mailto:equest-users@lists.onebuilding.org"
target="_blank" href="mailto:equest-users@lists.onebuilding.org">equest-users@lists.onebuilding.org</a><br><b>Subject:</b> [Equest-users] 90.1 App G Fan Power and EER Calculations</p></div></div><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">I’m sure this must have been asked before but I cannot find an answer in the archives – if there is one please point me to it.</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">I have interpreted the requirements of 90.1, App. G to split the EER of cooling equipment with a supply fan into its components to model the fan energy separately as follows:</p><p class="MsoNormal" style=""> </p><p class="MsoListParagraph">1. Say a space has a cooling load of 80,000Btu/h and the system is packaged single zone, EER – 11.2.</p><p class="MsoListParagraph">2. Calculate airflow for 20°F temperature
difference – 3708cfm</p><p class="MsoListParagraph">3. Calculate fan bhp from Table G3.1.2.9 – 3.49bhp</p><p class="MsoListParagraph">4. Calculate fan power as per G3.1.2.9 – 2972W</p><p class="MsoListParagraph">5. Calculate gross input power from load and EER – 7143W</p><p class="MsoListParagraph">6. Subtract 4 from 5 for compressor/condenser input power – 4171W</p><p class="MsoListParagraph">7. Convert to EIR – 0.1779</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">This appears to make sense from reading App. G but ends up with high fan power consumption and low space cooling loads. Am I wrong here?</p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style="">Thanks,</p><p class="MsoNormal" style=""> </p><p
class="MsoNormal" style=""><b>Steven Burley</b></p><p class="MsoNormal" style=""> </p></div></div></div></div></div>
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