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<p class="MsoNormal">Hello everybody,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am trying to calculate the Carnot COP (heating mode) of the heat pump used in type 927 (the default pump, which is the TRANE WPWD 024), however I am having trouble determining the evaporator and condenser temperatures.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">From online catalogues, I found that the refrigerant used is R22, but I didn¡¯t find anything else regarding the refrigerant circuit (only the water circuits).<o:p></o:p></p>
<p class="MsoNormal">So I had to make some assumptions in order to get some results:<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span><![endif]>saturated vapour at the evaporator outlet<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span><![endif]>saturated liquid at the condenser outlet<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span><![endif]>isenthalpic expansion at the throttle<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The problem then is that I have not been able to find the compressor efficiency (function of COP?) nor the ¦¤T between the refrigerant and the water streams in both evaporator and condenser (also function of COP?)¡­<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have tried making some realistic assumptions, but unfortunately results were inconsistent (I assumed a linear relationship between compressor efficiency and COP (60% to 80% for a COP of 3.8 to 5), and linear relationship between the ¦¤T
 and COP (14C to 28C in the range of 3.8 to 5)). I also assumed that the ¦¤T is the same between the refrigerant and the water in the evaporator as that of the refrigerant and the water in the condenser.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does anyone know if it is even possible to determine the Carnot COP by making such assumptions? Or does anyone have any extra data regarding this heat pump (or any heat pump for that matter) ?<br>
<br>
<o:p></o:p></p>
<p class="MsoNormal">Any suggestions/help would be great,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks again,<o:p></o:p></p>
<p class="MsoNormal">Ciar¨¢n<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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