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<p class=MsoNormal>Dear Friends,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have met a problem when using 2-pipe loop for air
conditioning. The model is an office tower with chillers and water source heat
pumps in the plant.<o:p></o:p></p>
<p class=MsoNormal>The cooling load will be taken by chillers and heat pumps
(cooling mode) and heating load will be taken only by heat pump. All the
airside systems are 4pipe. CHW loop and 2-pipe loop are created for cooling and
heating separately. For the VAV system(PIU in equest) it is OK, while for CAV
system(single zone reheat in equest) when I using 2-pipe for zone hot water
loop and chw loop in system cooling, there is only heating but no cooling
output.<o:p></o:p></p>
<p class=MsoNormal>I am confused about the results and guessing maybe the
cooling coil could not be attached to another chw loop when heating coils is in
a 2-pipe loop.<o:p></o:p></p>
<p class=MsoNormal>Anyone has some ideas about this odd thing? And is there another
approach to model my system?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks!<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Jie Zhang<span style='font-size:10.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt'><o:p> </o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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