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<p class="MsoNormal"><span style="color:#1F497D">Thanks for the reply. Yeah I already set the cooling control to Warmest in the model. If I change it back to “reset” (default in equest for VAV) my reheat load will be significantly higher.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Even with warmest in cool control, I have a lot of reheat in summer shoulder which doesn’t make sense to me.<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">Ali<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<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""> Kathryn Kerns [mailto:kathryn.kerns@bceengineers.com]
<br>
<b>Sent:</b> Monday, December 18, 2017 1:22 PM<br>
<b>To:</b> Alireza Mohammadzadeh; equest-users@onebuilding.org<br>
<b>Subject:</b> RE: VAV with Reheat in Summer<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I was having the same issues and had difficulty explaining how the PVAV system works. After a lot of trial and error, I discovered one thing that affects the VAV reheat in the warmer months and one thing that affects the amount of mechanical
cooling in the cooler months.<o:p></o:p></p>
<ol style="margin-top:0in" start="1" type="1">
<li class="MsoNormal" style="mso-list:l0 level1 lfo1">The “Cooling Control” variable under the Cooling Tab affects the amount of reheat that occurs in the summer months. There is a great deal of difference in the amount of reheat if you use the ASHRAE baseline
5 delta F reset based on outside air temperature and using the “Warmest” option. Try it, and you will see.<o:p></o:p></li><li class="MsoNormal" style="mso-list:l0 level1 lfo1">The “Economizer Low Limit” function located under the Outdoor Air tab, if available, usually shows up as 45 F. Lowering this down to 35 F will reduce the amount of mechanical cooling used in the cooler season.<o:p></o:p></li></ol>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hope this helps.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:black">Kathryn Kerns</span></b><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:"Arial","sans-serif";color:#1F497D">Systems Specialist</span></b><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif";font-variant:small-caps;color:teal">BCE</span></b><b><span style="font-size:10.0pt;font-family:"Times New Roman","serif";font-variant:small-caps;color:teal">
</span></b><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif";font-variant:small-caps;color:teal">Engineers, Inc.<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:9.0pt;font-family:"Times New Roman","serif";color:black">| Ph: 253.922.0446 | Fx: 253.922.0896 |</span></b><span style="font-size:7.0pt;font-family:"Times New Roman","serif";color:black">
<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b>From:</b> Equest-users [<a href="mailto:equest-users-bounces@lists.onebuilding.org">mailto:equest-users-bounces@lists.onebuilding.org</a>]
<b>On Behalf Of </b>Alireza Mohammadzadeh via Equest-users<br>
<b>Sent:</b> Monday, December 18, 2017 12:41 PM<br>
<b>To:</b> <a href="mailto:equest-users@onebuilding.org">equest-users@onebuilding.org</a><br>
<b>Subject:</b> [Equest-users] VAV with Reheat in Summer<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi eQUEST users,<o:p></o:p></p>
<p class="MsoNormal">I’m modelling a building that uses VAV with reheat for perimeter and interior zones. The min flow ratio at zone level can’t be less than 1, and I set the design flow to match our design.<o:p></o:p></p>
<p class="MsoNormal">I get a lot of reheat in summer shoulder, and when I look at the hourly report it seems like my central coil is cooling down the intake and zone coil reheats it. I only have one thermal zone for each VAV at this stage, and I’m sure that
summer reheat is not because of humidity control.<o:p></o:p></p>
<p class="MsoNormal">Any suggestion how I can get rid of the large should season reheat?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advanced <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">P.S., I attached INP and PD2 files.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Ali Mo, EIT<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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