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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I measure floor to floor whether I have return air plenums or ducted returns.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>My thinking is that there is heat gain/loss through the wall portion above a ceiling and below the floor above whether there is air flowing through it (RA plenum) or not (ducted returns). <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I have not tried any of the testing you’ve suggested, but now that you mention it, I might play with it a bit to see what happens.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Michael L. Hardy, PE, F.NSPE</span><span style='color:#1F497D'> <br></span><span style='font-family:"Tahoma","sans-serif";color:#1F497D'>Black Oak Engineering, Inc.<br></span><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>Cell 503.314.5244</span><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></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:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> hap-users-bounces@lists.onebuilding.org [mailto:hap-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Reba Schaber<br><b>Sent:</b> Thursday, February 17, 2011 6:39 PM<br><b>To:</b> hap-users@lists.onebuilding.org<br><b>Subject:</b> [Hap-users] A survey on measuring wall height<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>When measuring the wall height to determine the wall area, it’s clear the measurement should be floor to floor for return air plenums. Then the appropriate percentage is used in the wall-to-plenum heat gain field of the System’s duct system data.<o:p></o:p></span></p></div><div><p class=MsoNormal> <span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>How many HAP users still measure floor to floor when there is ducted return? Have you then entered the wall area by measuring floor to ceiling to check the effect on the load? What is that effect? <o:p></o:p></span></p></div><div><p class=MsoNormal> <span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>It is such a hassle to re-enter the wall area if the system changes from return air plenum to ducted return. It would seem the safest assumption is to enter wall areas by measuring wall height from floor to floor. Do you agree?<o:p></o:p></span></p></div><div><p class=MsoNormal> <span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div><div><p class=MsoNormal> <span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif"'> </span></b><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <span style='color:red'>PH</span></span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <u>MECHANICAL ENGINEERING<br></u> <b>Reba Schaber</b> Mechanical Engineer, P.E.<br> LEED Accredited Professional<br>1660 N. Alvernon Way Voice: (520) 731-2060<br>Tucson, Arizona 85712 Fax: (520) 731-2061<br> </span><span style='font-family:"Arial","sans-serif"'><a href="mailto:rschaber@phmech.com"><span style='font-size:10.0pt'>rschaber@phmech.com</span></a></span><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div><div><p class=MsoNormal> <span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div><div><p class=MsoNormal> <span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p></div></div></body></html>