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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi folks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m modeling a packaged VAV system (PVAVS) serving only one zone. The maximum airflow the unit can provide is 450,000 cfm, which I have entered in as an airflow parameter. The problem is that whenever the system goes into heating mode, the total cfm goes to minimum airflow (observed from hourly output), even when more heating is needed, so I end up with a lot of underheated hours. The minimum airflow is calculated from the 10% outdoor air ratio I have entered. I have tried adjusting the HMAX-FLOW-RATIO field to allow the heating airflow to go above the minimum if necessary, but the field seems to have no effect. I have a reverse action thermostat in the zone. Anyone else run into this? There must be some other parameter I’m using that is preventing the field from working. Any advice would be appreciated, as I have tried a lot of input variations and none of them allowed the heating minimum flow to increase when more heat is needed. I’m using eQuest 3.64.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks for your help!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Rosie<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='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>Roselin Osser, BEMP, LEED AP<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>Building Science Corporation<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>30 Forest Street<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>Somerville, MA 02143<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>978-589-5100 x 5284<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>fax: 978-589-5103<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>Building Science Corporation<br>Somerville MA | Waterloo ON<br><a href="http://www.buildingscience.com/"><span style='color:blue'>www.buildingscience.com</span></a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>