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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'>If you’re talking about a Dedicated Outdoor Air Supply (DOAS) of system, where there is additional equipment that is able to heat and cool and controls the individual zone temperatures, then I usually try to select a supply air temperature setpoint that will minimize the amount of reheat or recooling required. A precise answer would have to take into account the specific building (how many zones are in heating verses cooling at the same time), the climate (whether predominately heating or cooling) and the efficiency of the DOAS and zone equipment. The goal would be to select a temperature that will be the most efficient given all the different variables that go into each project.<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'>For me, where most of my projects are in a heating-dominated climate (northwest US) and there aren’t very many annual hours where pre-cooling is necessary, I usually keep my temperature close to my cooling setpoint (58 F in your example). This way, I’m preheating up to 58 F, then the zone equipment can continue heating, but there is very little cooling necessary. If my projects are in a predominately cooling dominated climate (CA and HI), where there is very little need for heating, then the same 58 F supply air setpoint works without much reheating.<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'>If you are talking about make-up air systems WITHUOT additional equipment to provide zone temperature controls, then my make-up air temperature setpoints are all over the map depending on things like what is the acceptable room temperature range (45 – 95 F??), how much internal load is generated (ovens, equipment, etc??) and again, whether the project is located I a predominately heating or cooling climate.<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'>If HAP could add a supply air temperature reset schedule similar to the Hot/Cold water reset schedules for Plants, then we could get more realistic results from our air systems.<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'>Good luck! <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><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Arial","sans-serif";color:black'>Michael L. Hardy, PE, F.NSPE</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> <br></span><span style='font-size:11.0pt;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='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> <o:p></o:p></span></p></div><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>dele omotayo<br><b>Sent:</b> Tuesday, February 05, 2013 7:13 AM<br><b>To:</b> Hap-users@lists.onebuilding.org<br><b>Subject:</b> [Hap-users] what is the required fresh air supply temp?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal style='background:white'><span style='font-size:14.0pt;color:black'>By default, the central cooling(from air system properties--system component tab) supply temp is 58 F which is the desired supply temp for just cooling. My question is, what should the temp be if the system is to be designed to temper outdoor air i.e what is the fresh air supply temp?<o:p></o:p></span></p></div></div></div></body></html>