<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:Wingdings;
panose-1:5 0 0 0 0 0 0 0 0 0;}
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:"Yu Gothic";
panose-1:2 11 4 0 0 0 0 0 0 0;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:"\@Yu Gothic";
panose-1:2 11 4 0 0 0 0 0 0 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
{mso-style-priority:34;
margin-top:0in;
margin-right:0in;
margin-bottom:0in;
margin-left:.5in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:246352446;
mso-list-type:hybrid;
mso-list-template-ids:1658111388 67698703 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}
@list l0:level1
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level2
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level3
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level4
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level5
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level6
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level7
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level8
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level9
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal">Hi Paul,<o:p></o:p></p>
<p class="MsoNormal"><br>
Since you didn’t provide a PRD, I presume you aren’’t doing this via parametric runs, but that means you’ll need to additionally specify exactly how you’re trying to enact a loop reset sequence so that others can help identify what may be going wrong. In lieu
of that however, I took some liberties to demonstrate one approach. Attached is a simple PRD to paste adjacent to the other project files (inp/pd2).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve done only 2 things:<o:p></o:p></p>
<ol style="margin-top:0in" start="1" type="1">
<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">I noticed the entry for MIN-RESET-T was at a default of 40, whereas your loop design temperature is specified at 50. I’ve adjusted this minimum bounding the reset behavior to matching
your CHW loop’s design temp. Note this input has zero impact in the baseline run, where the setpoint control is simply “fixed” (no reset). I’d hazard a guess here that if you missed this step, the loop would upon enabling a reset sequence push the chillers
to produce colder water – that could be the source of the negative savings you were seeing before.<o:p></o:p></li></ol>
<p class="MsoNormal" style="margin-left:.5in"><img width="753" height="572" style="width:7.8437in;height:5.9583in" id="Picture_x0020_2" src="cid:image003.png@01D42553.3C163A70"><o:p></o:p></p>
<ol style="margin-top:0in" start="2" type="1">
<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">I set up a simple parametric run to only swap the loop’s COOL-SETPT-CTRL from “Fixed” to “Load Reset.” This will cause the requested supply CHW temp to scale linearly from 50 to 65
in proportion to the relative load on the loop each hour.<o:p></o:p></li></ol>
<p class="MsoListParagraph"><img width="634" height="133" style="width:6.6041in;height:1.3854in" id="Picture_x0020_3" src="cid:image004.png@01D42553.8E7BD360"><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">On simulating both runs, I find the expected positive savings in “Space Cooling” (your chiller compressors aren’t having to work as hard/often), and a minor but negative savings in the heat rejection end use (your dry cooler is trying to
reject the same amount of Btu’s over the year with slightly warmer water in the condenser loop
<span style="font-family:Wingdings">à</span> more cooler fan runtime). <o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><b><u>Before:<o:p></o:p></u></b></p>
<p class="MsoNormal" style="margin-left:.5in"><img width="818" height="450" style="width:8.5208in;height:4.6875in" id="Picture_x0020_5" src="cid:image005.png@01D42556.4536EE30"><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><b><u><o:p><span style="text-decoration:none"> </span></o:p></u></b></p>
<p class="MsoNormal" style="margin-left:.5in"><b><u>After:<o:p></o:p></u></b></p>
<p class="MsoNormal" style="margin-left:.5in"><img width="821" height="458" style="width:8.552in;height:4.7708in" id="Picture_x0020_4" src="cid:image006.png@01D42556.4536EE30"><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
<p class="MsoNormal">Finally, as you made reference to airside fan VFD’s… I don’t think you should expect interaction with the fan energies in the case of using “load reset” (which is supposed to reflect a sequence wherein the BAS is directing the loop setpoint
to satisfy the whole buildings per the worst-case coil’s valve position). Implicitly, the sequence won’t be letting the CHW rise to a temperature that results in an AHU being unable to satisfy it’s duties for lack of airflow/runtime.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Intuitively, I would however caution that if you have or intend to specify variable flow on the associated CHW loop
<u>pump(s)</u>, that would be something meaningful to input correctly that I’m not seeing at the moment (I observe single speed pumps and 3-way valves at the airside CHW coils). If you do need to work in variable flow pumping concurrently with a temp reset
sequence, you should review/coordinate with the sequence specification to ensure you are correctly picking up on when to let the pump’s turndown lead vs. allowing the temps to reset (else they can end up fighting each other and burning more energy). This
is manipulated in eQuest via the LOOP-FLOW-RESET fraction.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hope this helps you and others!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">~Nick<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#3A7A46"><img width="726" height="9" style="width:7.5625in;height:.0937in" id="Picture_x0020_1" src="cid:image001.png@01D42552.8B7C6B80"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:"Arial",sans-serif;color:#3A7A46">Nick Caton, P.E., BEMP</span></b><span style="color:#3A7A46"><o:p></o:p></span></p>
<table class="MsoNormalTable" border="0" cellspacing="0" cellpadding="0" width="724" style="width:543.0pt;border-collapse:collapse">
<tbody>
<tr>
<td width="230" valign="top" style="width:172.3pt;padding:0in 0in 0in 0in">
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469"> Senior Energy Engineer</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D"><br>
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469"> Regional Energy Engineering Manager<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469"> Energy and Sustainability Services</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D"><br>
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469"> Schneider Electric</span><span style="color:#1F497D"><o:p></o:p></span></p>
</td>
<td width="291" valign="top" style="width:218.3pt;padding:0in 0in 0in 0in">
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#57B069">D </span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469">913.564.6361
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D"><br>
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#57B069">M </span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469">785.410.3317
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D"><br>
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#57B069">F </span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469">913.564.6380</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D"><br>
</span><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#57B069">E </span><span style="color:#1F497D"><a href="mailto:nicholas.caton@schneider-electric.com"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469">nicholas.caton@schneider-electric.com</span></a><o:p></o:p></span></p>
</td>
<td width="203" valign="top" style="width:152.4pt;padding:0in 0in 0in 0in">
<p class="MsoNormal" align="right" style="text-align:right"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#626469">15200 Santa Fe Trail Drive<br>
Suite 204<br>
Lenexa, KS 66219<br>
United States</span><span style="color:#1F497D"><o:p></o:p></span></p>
</td>
</tr>
<tr style="height:4.0pt">
<td width="724" colspan="3" valign="top" style="width:543.0pt;padding:0in 0in 0in 0in;height:4.0pt">
<p class="MsoNormal" style="mso-line-height-alt:4.0pt"><span style="color:#3A7A46"><img border="0" width="722" height="49" style="width:7.5208in;height:.5104in" id="_x0000_i1025" src="cid:image002.png@01D42552.8B7C6B80"><!--[if gte mso 9]><xml>
<o:OLEObject Type="Embed" ProgID="PBrush" ShapeID="_x0000_i1025" DrawAspect="Content" ObjectID="_1594165720">
</o:OLEObject>
</xml><![endif]--><o:p></o:p></span></p>
</td>
</tr>
</tbody>
</table>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> Equest-users [mailto:equest-users-bounces@lists.onebuilding.org]
<b>On Behalf Of </b>Paul Graves via Equest-users<br>
<b>Sent:</b> Wednesday, July 25, 2018 7:46 AM<br>
<b>To:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> [Equest-users] Data center CHW reset negative savings<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">Good morning all! I was advised to include our model files in case someone could take a quick look at them and tell us the error of our ways. I would still be happy to reimburse anyone for time spent! The problem we encountered was we saw
negative chiller savings from resetting the CHW. I expect we made a mistake, but since the fans also have VFDs, it's possible we increase fan energy while saving a little on the chiller, but it still doesn't look right. Any help appreciated. Thank you eQuest
users for the help already provided!<o:p></o:p></p>
<div>
<p class="MsoNormal"><br clear="all">
<o:p></o:p></p>
<div>
<div>
<div>
<div>
<p class="MsoNormal"><strong><span style="font-family:"Calibri",sans-serif">Paul Graves</span></strong><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">(303) 887 6015<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
<p class="MsoNormal"><br>
______________________________________________________________________<br>
This email has been scanned by the Symantec Email Security.cloud service.<br>
______________________________________________________________________<o:p></o:p></p>
</div>
</body>
</html>