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<p class=MsoNormal>Hello All,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I searched the archives and found some mention of chiller
curves, but not much dealing with this particular issue. I understand the
concept of the three different ratios for the condenser water temperature, PLR
and dT, and capacity curve. What concerns me is the part load curve.
I was doing some investigation and put the DOE2 default coefficients into an
excel file (attached) for a water cooled, centrifugal hermetic chiller.
Only changing the part load ratio, the kW/ton of the chiller decreases
dramatically, which isn’t correct. Logic tells me that decreasing
the condenser water temperature should increase efficiency, and decreasing the
part load ratio should decrease efficiency. Am I missing something here?
Has anyone run into this issue or corrected it?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='text-autospace:none'><b><span style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:#005480'>Todd Lagus, EIT<o:p></o:p></span></b></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:8.0pt;
font-family:"Arial","sans-serif";color:#807F83'>Mechanical Engineer<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:8.0pt;
font-family:"Arial","sans-serif";color:#807F83'>Sebesta Blomberg <br>
sebesta.com</span><span style='font-size:8.0pt;font-family:"Arial","sans-serif"'>
<span style='color:#807F83'>| P 651.634.7236 | F 651.634.7400<o:p></o:p></span></span></p>
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