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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Hi Brian,<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'>Thanks for the quick reply. I understand where you’re coming from, but 100% free cooling was always available before I increased the OA intake. The free cooling credit for both scenarios should be the same. If the building had no economizers, then yes, bringing in more OA will help with the cooling. There are definitely humid days where free cooling is not available, and bringing in more OA on those days should increase the overall cooling energy use.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:9.0pt;text-transform:uppercase;letter-spacing:.2pt'>VICTOR YEUNG, </span></b><i><span style='font-size:9.0pt;letter-spacing:.2pt'>BASc, LEED® AP BD+C</span></i><o:p></o:p></p><p class=MsoNormal><i><span style='font-size:8.0pt;font-family:"Cambria","serif";color:#262626;letter-spacing:.2pt'><a href="mailto:victor@invirosystems.ca">victor@invirosystems.ca</a></span></i><o:p></o:p></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> Brian Fountain [mailto:bfountain@greensim.com] <br><b>Sent:</b> November-03-11 1:03 PM<br><b>To:</b> Victor Yeung<br><b>Subject:</b> Re: [Equest-users] OA Intake on Energy Use<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I suspect (but don't know) that it is the difference between peak and overall annual energy use. Yes, by bringing in more OA the peak cooling will go up (check SS-D) but there is more OA available for free cooling so the overall cooling energy goes down.<br><br>On 11/3/2011 12:33 PM, Victor Yeung wrote: <o:p></o:p></p><p class=MsoNormal>Hello modelling gurus,<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>I am modelling a restaurant space located in Canada serve by PSZ rooftop units. I notice something weird when I increase the OA intake for the space. Space heating energy use goes up as expected, but cooling energy use went down a tad bit. This doesn’t make sense as I’m bringing in more hot/humid OA to the space. I’ve already setup dual enthalpy economizers for the PSZ units, so I don’t think it’s a problem with free cooling.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>Anyone can point out what’s going on?<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>Regards,<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><b><span style='font-size:9.0pt;text-transform:uppercase;letter-spacing:.2pt'>VICTOR YEUNG, </span></b><i><span style='font-size:9.0pt;letter-spacing:.2pt'>BASc, LEED® AP BD+C</span></i><o:p></o:p></p><p class=MsoNormal><i><span style='font-size:8.0pt;font-family:"Cambria","serif";color:#262626;letter-spacing:.2pt'><a href="mailto:victor@invirosystems.ca">victor@invirosystems.ca</a></span></i><o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><br><br><br><o:p></o:p></span></p><pre>_______________________________________________<o:p></o:p></pre><pre>Equest-users mailing list<o:p></o:p></pre><pre><a href="http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org">http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding..org</a><o:p></o:p></pre><pre>To unsubscribe from this mailing list send a blank message to <a href="mailto:EQUEST-USERS-UNSUBSCRIBE@ONEBUILDING.ORG">EQUEST-USERS-UNSUBSCRIBE@ONEBUILDING.ORG</a><o:p></o:p></pre><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><br><br><br><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com">www.avg.com</a><br>Version: 2012.0.1834 / Virus Database: 2092/4593 - Release Date: 11/03/11<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:windowtext'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com">www.avg.com</a><br>Version: 2012.0.1834 / Virus Database: 2092/4593 - Release Date: 11/03/11<o:p></o:p></span></p></div></body></html>