<html><head></head><body><div class="ydp9b35a8d3yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div><div dir="ltr" data-setdir="false">Hi Sharad:</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">I can't find any heat exchangers in my model. How did you pull up the heat exchanger screen?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Thank you,<br></div><div><br></div><div class="ydp9b35a8d3signature">Paul Diglio<br>87 Fairmont Avenue <br>New Haven, CT 06513 <br></div></div><br><div><br></div>
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On Tuesday, December 10, 2019, 9:29:01 AM EST, Sharad Kumar via Equest-users <equest-users@lists.onebuilding.org> wrote:
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<div><div id="ydpbe1b492ayiv4550911065"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div><font color="#073763">Hi Paul,</font></div><div><font color="#073763"><br></font></div><div><span style="color:rgb(7,55,99);">I think the problem is being caused due to some heat exchanger kind of thing being modeled in the built.</span><br></div><div><font color="#073763"><br></font></div><div><font color="#073763">I am guessing out the problem as follows:</font></div><div><font color="#073763"><br></font></div><div><font color="#073763">The UA calculations does not converge as there can be might possibility that then UA product and after multiplication with delta T does not converge with the meeting of the capacity as the formula is Q= U* A* delta T.</font></div><div><font color="#073763"><br></font></div><div><font color="#073763">Q= Capacity</font></div><div><font color="#073763">UA= product of conductance and cross sectional area.</font></div><div><font color="#073763">delta T= Temperature difference between ends.</font></div><div><font color="#073763"><br></font></div><div><div><font color="#073763"><img src="cid:atpXJw1aUxE63Vy5mnLn" alt="image.png" data-inlineimagemanipulating="true" style="width: 534px; max-width: 572px;"><br></font></div><font color="#073763">
</font></div><div><font color="#073763">Hence try to succumb with the problem in lieu-wise as above.</font></div><div><font color="#073763"><br></font></div><div><font color="#073763"><br></font></div><div><div><img src="cid:gN4oFXesa4v5gH4p91ac" alt="image.png" data-inlineimagemanipulating="true" style="width: 386px; max-width: 386px;"><br></div></div><div><font color="#073763"><br></font></div><div><font color="#073763">The other factors to have the UA product calculations to be right are as in above help page super-script which might can also guide as there are other factors based calculations is there as if there the boxed figure are outrun.</font></div><div><font color="#073763"><br></font></div><div><font color="#073763">Hope this might help.</font></div><div><br></div><div><b><font color="#073763">Thanks and regards,</font></b></div><div><font color="#073763">Sharad.Kumar</font></div><div><font color="#073763">Freelancer-Energy Simulation and Day-lighting.</font></div><div><font color="#073763"><br></font></div><div dir="ltr"><b><font color="#20124d">....................................................................................................................................................</font></b>.</div><div dir="ltr"><br></div><div dir="ltr">---------- Forwarded message ----------<br>From: Paul Diglio <<a href="mailto:paul.diglio@sbcglobal.net" rel="nofollow" target="_blank">paul.diglio@sbcglobal.net</a>><br>To: Equest-users <<a href="mailto:equest-users@lists.onebuilding.org" rel="nofollow" target="_blank">equest-users@lists.onebuilding.org</a>><br>Cc: <br>Bcc: <br>Date: Mon, 9 Dec 2019 11:13:13 +0000 (UTC)<br>Subject: [Equest-users] UA Convergence Error<br><div><div style="font-family:Helvetica, Arial, sans-serif;font-size:16px;"><div dir="ltr">Hi Folks:</div><div dir="ltr"><br></div><div dir="ltr">I am getting a "heat exchanger XX Sys1 UA calculation failed to converge" error. The model has three building in it and only two air handlers per building. I don't have any heat exchangers attached to the air handlers or any heat recovery installed.<br></div><div dir="ltr"><br></div><div dir="ltr">Sometimes the error occurs when I change the glass type via the library and other times I get the error when I adjust the air changes per hour in one or two zones.</div><div dir="ltr"><br></div><div dir="ltr">In the example above, the error was for system B2, but it varies...sometimes systems A or C 1 or 2.</div><div dir="ltr"><br></div><div dir="ltr">Any ideas what the problem could be? <br></div><div dir="ltr"><br></div><div dir="ltr">Thank you,<br></div><div><br></div><div>Paul Diglio<br>87 Fairmont Avenue <br>New Haven, CT 06513 <br><br><br></div></div></div>_______________________________________________<br>Equest-users mailing list<br><a href="mailto:Equest-users@lists.onebuilding.org" rel="nofollow" target="_blank">Equest-users@lists.onebuilding.org</a><br><a href="http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org" rel="nofollow" target="_blank">http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org</a><br></div></div></div></div></div>_______________________________________________<br>Equest-users mailing list<br><a href="http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org" rel="nofollow" target="_blank">http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org</a><br>To unsubscribe from this mailing list send a blank message to <a href="mailto:EQUEST-USERS-UNSUBSCRIBE@ONEBUILDING.ORG" rel="nofollow" target="_blank">EQUEST-USERS-UNSUBSCRIBE@ONEBUILDING.ORG</a><br></div>
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