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Michał,<br>
Type938 does not take a defrosting cycle into account because the
sequence of controls used to run a defrost cycle change from one
manufacturer to another. You can create your own defrost cycle,
however by using a thermostat model to watch the outdoor unit outlet
temperature and turn the heat pump on in cooling mode for a period
if the outlet air temperature falls too far. Depenging on how the
defrost cycle works in your case you can also use some other
components if an electric heater runs to keep the supply air warm
during that cycle.<br>
<br>
As a side note, please remember that Type938 (and all the
components that read performance data from an external data file)
can interpolate performance data within the range given in the file
but cannot extrapolate beyond the range. If you expect to run your
heat pump in a climate where defrost will be needed please also make
sure that both the heating and cooling data files contain capacity
and input power information for temperatures that low.<br>
kind regards,<br>
David<br>
<br>
<br>
<div class="moz-cite-prefix">On 5/20/2015 8:30 AM, Michał Klimas
wrote:<br>
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<p class="MsoNormal">Dear All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I’m trying to simulate
the behavior of air source heat pump during a year. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Does anyone know how to
take into account <b>defrosting cycle</b> (reverse mode of
heat pump) during winter time ?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">kind regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Michal Klimas<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Poznan University of
Technology<o:p></o:p></span></p>
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<pre class="moz-signature" cols="72">--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
Madison, WI 53703 USA
P:+1.608.274.2577
F:+1.608.278.1475
<a class="moz-txt-link-abbreviated" href="mailto:d.bradley@tess-inc.com">d.bradley@tess-inc.com</a>
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