<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><DIV>Bryce:</DIV>
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<DIV>Forgive my systems ignorance. But if you have a single fan dual duct system, don't the hot and cold deck dampers just swing from heating to cooling? How will the airflow vary unless you have two fans?</DIV>
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<DIV>I can learn as well from our well versed members.</DIV>
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<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Bryce Munger <BMunger@glumac.com><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> equest-users@lists.onebuilding.org<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Tue, February 1, 2011 10:46:02 AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> [Equest-users] Dual Duct VAV problems<BR></FONT><BR>
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<P class=MsoNormal><SPAN style="FONT-FAMILY: 'sans-serif'; FONT-SIZE: 11pt">I am working on a dual duct simulation and I am having trouble getting vav control to work correctly. The system is defined as a 100% OA Dual Duct Single Fan system and I have tried everything I can think of to get the fans to vary. When the sim runs, the fans are pegged in the 90-100% range all year. When I change to a dual fan dual duct system, the fans will act as a vav fan is expected with a range of operating hours throughout the year. I have tried Fan Control of “Variable Speed” and “Fan EIR FPLR” without success. Any ideas?</SPAN></P>
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<P class=MsoNormal><SPAN style="FONT-FAMILY: 'sans-serif'; FONT-SIZE: 11pt">Thanks, </SPAN></P>
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<P class=MsoNormal><SPAN style="FONT-FAMILY: 'sans-serif'; FONT-SIZE: 11pt">Bryce</SPAN></P>
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