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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:14.0pt;color:#2E75B6;mso-style-textfill-fill-color:#2E75B6;mso-style-textfill-fill-alpha:100.0%'>Dear friends<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#2E75B6;mso-style-textfill-fill-color:#2E75B6;mso-style-textfill-fill-alpha:100.0%'>Please check my simple circuit. A 150 kg tank is supposed to be maintained at 60 degrees all year. A flat plate collector has been employed. When you run the simulation (file FPC1), you see some sharp rises of collector outlet temperature, as high as 400 degrees, which are obviously wrong. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#2E75B6;mso-style-textfill-fill-color:#2E75B6;mso-style-textfill-fill-alpha:100.0%'>If you remove the type2b controller and, for example, control the pump with type14h (file FPC2), the sharp rises disappear. It seems type2b is responsible for the errors in the first case. Thank you very much for your kind help.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#2E75B6;mso-style-textfill-fill-color:#2E75B6;mso-style-textfill-fill-alpha:100.0%'>Hooman<o:p></o:p></span></p></div></body></html>