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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Josh,<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'>You need to consider fan heat. If it’s a draw-through coil, then
eQUEST knows that the SAT leaving the coil needs to be lower than the zone
entering temperature. So in your case, when you enter 55F for zone entering
temperature, then the coil leaving temperature is 55F minus the fan delta T. <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'>-Erik Kolderup<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'><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"'>
equest-users-bounces@lists.onebuilding.org
[mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Josh
Doherty<br>
<b>Sent:</b> Wednesday, April 22, 2009 10:16 AM<br>
<b>To:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> [Equest-users] CHW temp and cooling coil leaving temp<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>HI,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I
am trying to model a VAV system for cooling and heating. On the cooling
side, I specify a 52F CHW loop temperature and a “Zone Entering Min Supply
Temp” of 55F. When I run the simulation I get an error that states
“cooling coil leaving temperature must be at least 6F higher than entering
water temp”. I played with adjusting the “Zone Entering Min Supply Temp”
to see what minimum value would work without errors and the lucky number was
61F. I am trying to figure out why this is the minimum temperature eQuest
accepts without errors. The 61F is 9F higher than the entering water
temperature and not 6F like the error states. Any ideas what is going on?
Thanks so much for your help and insight.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><strong>Josh Doherty</strong><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><o:p> </o:p></p>
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