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<p class=MsoNormal><span style='color:#1F497D'>With some further
experimentation I have been able to make the cooling tower work using a fixed
setpoint control for the loop.<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'>If anyone has any experience
with loop control in conjunction with cooling towers and can give me some pointers
regarding the limitations, I would be very thankful.<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'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Regards,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'>MaryAnne
Mason</span></b><span lang=FR-CA style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Mechanical Engineer</span><span lang=FR-CA style='font-size:
10.0pt;font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Process Infrastructure</span><span lang=FR-CA style='font-size:
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color:#365F91'> </span><span lang=FR-CA style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Ausenco Sandwell</span><span lang=FR-CA style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>1016B Sutton Drive, Suite 100</span><span lang=FR-CA
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Burlington ON L7L 6B8</span><span lang=FR-CA style='font-size:
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style='color:#365F91'>maryanne.mason@ausencosandwell.com</span></a> <br>
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color:#365F91'>W</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'> </span><span lang=FR-CA style='font-size:10.0pt;
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href="http://www.ausenco.com/"><span lang=EN-US style='color:#365F91'>www.ausenco.com</span></a>
<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'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
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<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>Maryanne
Mason<br>
<b>Sent:</b> Wednesday, August 04, 2010 4:15 PM<br>
<b>To:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> [Equest-users] Water-side free cooling<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Hi All,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have specified a chiller as water economizer to create a
free cooling heat exchanger, with a cooling tower that represents a heat sink
that is actually a canal. The cooling tower was added so that the program would
use the cooling tower conditions to determine if the free cooling heat
exchanger could run. The loop connected to the cooling tower is scheduled for
the actual monthly conditions of the canal.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>By reviewing hourly operating values for the free cooling
system, I have discovered that the actual temperature of the canal is being
offset downwards whenever there is a large load, regardless of the actual
scheduled setpoint. (The larger the load, the lower the setpoint value.)<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>In addition, the cooling tower output values are all zero, leading
me to believe that it is not operating at all.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I would greatly appreciate any assistance provided for
either of these problems.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='color:#1F497D'>Regards,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'>MaryAnne
Mason</span></b><span lang=FR-CA style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Mechanical Engineer</span><span lang=FR-CA style='font-size:
10.0pt;font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Process Infrastructure</span><span lang=FR-CA style='font-size:
10.0pt;font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'> </span><span lang=FR-CA style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Ausenco Sandwell</span><span lang=FR-CA style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>1016B Sutton Drive, Suite 100</span><span lang=FR-CA
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Burlington ON L7L 6B8</span><span lang=FR-CA style='font-size:
10.0pt;font-family:"Arial","sans-serif";color:#365F91'> <br>
</span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>Canada</span><span lang=FR-CA style='font-size:10.0pt;
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"Arial","sans-serif";color:#365F91'> +</span><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'>1 905
319 1698</span><span lang=FR-CA style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'> <br>
</span><b><span lang=FR style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>F</span></b><span lang=FR style='font-size:10.0pt;font-family:
"Arial","sans-serif";color:#365F91'> +</span><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'>1
905 319 1801</span><span lang=FR-CA style='font-size:10.0pt;font-family:
"Arial","sans-serif";color:#365F91'> <br>
</span><b><span lang=PT-BR style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>E</span></b><span lang=PT-BR style='font-size:10.0pt;font-family:
"Arial","sans-serif";color:#365F91'> </span><span lang=FR-CA
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#365F91'><a
href="mailto:maryanne.mason@ausencosandwell.com"><span lang=PT-BR
style='color:#365F91'>maryanne.mason@ausencosandwell.com</span></a> <br>
</span><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'>W</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#365F91'> </span><span lang=FR-CA style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:#365F91'><a
href="http://www.ausenco.com/"><span lang=EN-US style='color:#365F91'>www.ausenco.com</span></a>
<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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