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<DIV>Hello,</DIV>
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<DIV>I am using eQUEST to model an Lab/Office building with Standard VAV w/Reheat system type throughout. The office spaces are isolated on a single VAV system, and one option I am adding by parametric run is an OA Temp economizer strategy. The supply air temperature set point (COOL-SET-T) is held constant at 55, and the maximum system level heating is also held to 55 degrees (HEAT-SET-T). What I'm noticing is that there is a significant heating increase with the addition of an economizer when OA-CONTROL is the only variable. This heating increase is outweighing any significant cooling or electricity savings resulting in an energy penalty. I had hoped that the economizer would only mix outside air with return air to maintain the 55 degree supply air temperature from the unit. Are there additional measures necessary to clearly define economizer control to prevent a heating increase, or is there a better way to define economizer control altogether?</DIV>
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<DIV>Thanks,</DIV>
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<DIV><STRONG><FONT size=2><FONT color=#800000>Matt Edwards <SPAN style="FONT-SIZE: 10pt; COLOR: maroon">LEED </SPAN><SPAN style="FONT-SIZE: 10pt; COLOR: maroon; FONT-FAMILY: Arial">® AP</SPAN></FONT></FONT></STRONG></DIV>
<DIV><FONT size=2>Mechanical Systems <FONT color=#800000>|</FONT> <STRONG><FONT color=#800000>Affiliated Engineers, Inc</FONT></STRONG></FONT></DIV>
<DIV><FONT size=2>5802 Research Park Blvd</FONT></DIV>
<DIV><FONT size=2>Madison, WI 53719</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Phone: (608) 236-1154 (direct)</FONT></DIV>
<DIV><FONT size=2>Fax: (608) 238-2614</FONT></DIV>
<DIV><FONT size=2>Email: <A href="mailto:medwards@aeieng.com">medwards@aeieng.com</A></FONT></DIV>
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