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<DIV><FONT color=#000000 size=2 face=Arial>Hi All, I'm modeling a system with heat pump chiller for heating and boilers as backup. When I specify the heating source for each space as Heat Pump I get the error saying that the HW loop has zero flow. Is there a way to fix this. It seems to work if I keep at least on space on the boiler system. I attached the file for anyone who is willing to help.</FONT></DIV>
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<DIV><FONT size=2 face=Arial>Much appreciated.</FONT></DIV>
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<DIV><FONT size=2 face=Arial>Bassam Yammine</FONT></DIV>
<DIV><FONT size=2 face=Arial>Flow Consulting</FONT></DIV></BODY></HTML>