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<DIV><SPAN class=961283218-22042008><FONT face=Arial color=#0000ff
size=2>Dana:</FONT></SPAN></DIV>
<DIV><SPAN class=961283218-22042008><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=961283218-22042008><FONT face=Arial color=#0000ff size=2>As I
know, there is no water-to-air heat pump (packaged unit not the multi-split VRF)
with variable speed compressor available on market yet though it is on the way.
However, there is heat pump with staged capacity, which is
typically implemented by 2-stage scroll compressor. I'm not sure how the
selection of variable speed compressor affect the boiler operation, but it seems
the variable speed compressor is not a valid option for water-to-air heat
pump.</FONT></SPAN></DIV>
<DIV><SPAN class=961283218-22042008><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=961283218-22042008><FONT face=Arial color=#0000ff
size=2>Xiaobing</FONT></SPAN></DIV>
<DIV><SPAN class=961283218-22042008></SPAN><FONT face=Tahoma><BR><FONT
size=2><SPAN class=961283218-22042008><FONT face=Arial
color=#0000ff> </FONT></SPAN>-----Original Message-----<BR><B>From:</B>
bldg-sim-bounces@lists.onebuilding.org
[mailto:bldg-sim-bounces@lists.onebuilding.org]<B>On Behalf Of </B>Dana
Troy<BR><B>Sent:</B> Tuesday, April 22, 2008 1:28 PM<BR><B>To:</B>
bldg-sim@lists.onebuilding.org<BR><B>Subject:</B> [Bldg-sim] PVVT Variable Speed
Compressors<BR><BR></FONT></DIV></FONT>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<P><FONT size=2>Hello everybody,<BR><BR>I am trying to simulate a water source
heat pump with a variable speed compressor in eQUEST. I have selected PVVT as
the system and have come across some interesting results.<BR><BR>When the
Single Speed compressor is selected under Cooling\Unitary Power\Cooling
Compressor, the PS-C report shows the boiler and cooling tower both operating
for various hours throughout the year, as expected. However, when the
compressor is changed to Variable Speed, the boiler operation hours disappear,
but the cooling tower hours remain. </FONT></P>
<P><FONT size=2>Is this because it simulates the heating DX coils as air
cooled but the cooling DX coils as water cooled? If so, this is not a
representation of a water source heat pump.</FONT></P>
<P><FONT size=2>Any insight will be greatly appreciated.</FONT></P>
<P><FONT size=2>Regards,</FONT></P>
<P><FONT size=2>Dana<FONT face=Arial size=2></FONT><FONT face=Arial
size=2></FONT><FONT face=Arial size=2></FONT></P>
<DIV><BR><STRONG><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Dana
Troy</SPAN></STRONG></DIV>
<DIV><STRONG><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></STRONG><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN><FONT face=Arial
size=2>Energy Analyst </FONT></DIV>
<DIV><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">LEED<SUP>®</SUP>
Accredited Professional</SPAN><BR><BR><A href="http://www.glumac.com/"><IMG
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<DIV><SPAN
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<DIV><SPAN
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