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<body class='hmmessage'><div dir='ltr'>Hello,<div><br></div><div>I am using this model to simulate a water heating system.</div><div>But there is always this problem "a negative flow was encountered". I have tried to change the flow of cold water income, and change "-2" to each of the 4 in/outlets of Type60f. However, it doesn't work.</div><div><br></div><div>Chen</div> </div></body>
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