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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>When using Energy Recovery Ventilation, the “ERV Fans:”
should always be specified as “Self Contained”. This way the
ERV Fan will only see the Outdoor Air and Exhaust Air Flow Rates.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>If “ERV Fans:” is specified as “HVAC
Supply/Return”, then the ERV Supply and Exhaust pressure drop are added
onto the HVAC Supply/Return fan pressure drop. This would mean that the
Total HVAC Air Flow Rate goes through the ERV which is incorrect. The ERV
only should see the Outdoor Air. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>To test this, I have run both conditions and by specifying “HVAC
Supply/Return”, the ventilation fan energy becomes extremely large.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Has this been a known bug or am I missing something.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Ian Doebber<o:p></o:p></span></font></p>
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