<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=iso-8859-1">
<meta name="Generator" content="Microsoft Word 12 (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:"MS Mincho";
panose-1:2 2 6 9 4 2 5 8 3 4;}
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:"\@MS Mincho";
panose-1:2 2 6 9 4 2 5 8 3 4;}
@font-face
{font-family:"Stylus BT";
panose-1:2 14 4 2 2 2 6 2 3 4;}
/* 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:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
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";}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
span.EmailStyle20
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:windowtext;}
span.EmailStyle21
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@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:629477364;
mso-list-type:hybrid;
mso-list-template-ids:-556991468 134807567 134807577 134807579 134807567 134807577 134807579 134807567 134807577 134807579;}
@list l0:level1
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level2
{mso-level-tab-stop:1.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level3
{mso-level-tab-stop:1.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level4
{mso-level-tab-stop:2.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level5
{mso-level-tab-stop:2.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level6
{mso-level-tab-stop:3.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level7
{mso-level-tab-stop:3.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level8
{mso-level-tab-stop:4.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level9
{mso-level-tab-stop:4.5in;
mso-level-number-position:left;
text-indent:-.25in;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="2050" />
</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="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal"><span style="color:#1F497D">Steve,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">There are two schools of thought for dealing with fan power in cooling efficiency calcs. The first pulls away the baseline fan power Pfan, as you’re describing, and the other instead pulls out a fan energy draw
based on ARI testing procedures… 400 CFM/ton </span><span style="font-family:Wingdings;color:#1F497D">à</span><span style="color:#1F497D"> 365W/1000CFM. I follow the latter these days, but see both as viable.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The two approaches result in similar results when your Pfan calculation doesn’t involve a lot of static pressure adders. When it does, the approaches diverge in a fashion that may be either problematic or helpful
in a LEED rating sense. Attached discussion sums up things further, includes an outline of an ARI-based approach. You can find more discussions and read into advantages/disadvantages to both approaches in the mailing list archives.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">That said, I haven’t checked your math or references but the procedure you’ve roughly outlined sounds alright for a Pfan approach. There are steps in between what you’ve written for correctly coming up with
Pfan, but I take it that’s implicit.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">~Nick<o:p></o:p></span></p>
<div>
<p class="MsoNormal"><span style="color:#1F497D"><img width="119" height="37" id="Picture_x0020_1" src="cid:image001.jpg@01CD3D7A.2E873610" alt="cid:489575314@22072009-0ABB"></span><b><span style="font-family:"Stylus BT","sans-serif";color:#2D4D5E"><o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-family:"Stylus BT","sans-serif";color:#2D4D5E"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E">NICK CATON, P.E.</span></b><b><span style="font-size:12.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E"><o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900">SENIOR ENGINEER<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">Smith & Boucher Engineers</span><span style="font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">25501 west valley parkway, suite 200<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">olathe, ks 66061<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">direct 913.344.0036<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">fax 913.345.0617<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><a href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span style="font-size:10.0pt">www.smithboucher.com</span></a></span><u><span style="font-size:10.0pt;color:blue">
</span></u><span style="color:#1F497D"><o:p></o:p></span></p>
</div>
<p class="MsoNormal"><span style="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""> equest-users-bounces@lists.onebuilding.org [mailto:equest-users-bounces@lists.onebuilding.org]
<b>On Behalf Of </b>Steve Burley<br>
<b>Sent:</b> Tuesday, May 29, 2012 6:37 AM<br>
<b>To:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> [Equest-users] 90.1 App G Fan Power and EER Calculations<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-GB">I’m sure this must have been asked before but I cannot find an answer in the archives – if there is one please point me to it.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I have interpreted the requirements of 90.1, App. G to split the EER of cooling equipment with a supply fan into its components to model the fan energy separately as follows:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Say a space has a cooling load of 80,000Btu/h and the system is packaged single zone, EER – 11.2.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Calculate airflow for 20°F temperature difference – 3708cfm<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">3.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Calculate fan bhp from Table G3.1.2.9 – 3.49bhp<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">4.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Calculate fan power as per G3.1.2.9 – 2972W<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">5.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Calculate gross input power from load and EER – 7143W<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">6.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Subtract 4 from 5 for compressor/condenser input power – 4171W<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:21.3pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span lang="EN-GB"><span style="mso-list:Ignore">7.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span lang="EN-GB">Convert to EIR – 0.1779<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">This appears to make sense from reading App. G but ends up with high fan power consumption and low space cooling loads. Am I wrong here?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span lang="EN-GB" style="font-family:"Arial","sans-serif";color:#002060">Steven Burley</span></b><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
</div>
</body>
</html>