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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I am confused as to what Tmin corresponds to within the cool
control range field. Below is the equest description:<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
text-indent:.5in'><b><i><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>COOL-CTRL-RANGE<o:p></o:p></span></i></b></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><i><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Throttling
range of the cooling coil controller. It equals Tmax - Tmin where Tmax is the
temperature of the coil when it is fully loaded and Tmin is the temperature of
the coil when it is fully unloaded.<o:p></o:p></span></i></p>
<p class=MsoNormal>Here is my current setup:<o:p></o:p></p>
<p class=MsoNormal>System: Central Plant CHW service with three way valves
serving the cooling coils. Assigned a deltaT of 12degF even though this
varies throughout the year.<o:p></o:p></p>
<p class=MsoNormal>Tmax: 40.1degF during summer (temps varies throughout
year but this is the lowest observed temp )<o:p></o:p></p>
<p class=MsoNormal>Tmin?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I tried varying this range from zero all the way up to the
deltaT of 12. A range of zero seems to make the model to more closely
match the utility data for this building. But, until I fully understand what Tmin
is, I cannot definitely say a range of zero is appropriate.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thank you in advance for your time.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><b><span style='font-family:"HelveticaNeueLT Std";
color:blue'>Michael Jochman</span></b><b><span style='font-family:"Times New Roman","serif";
color:#1F497D'><o:p></o:p></span></b></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"HelveticaNeueLT Std";
color:navy'>Project Engineer<o:p></o:p></span></p>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"HelveticaNeueLT Std";
color:blue'>JDR</span></b><span style='font-size:10.0pt;font-family:"HelveticaNeueLT Std";
color:navy'> Engineering, Inc.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"HelveticaNeueLT Std";
color:navy'><o:p> </o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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