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<DIV><SPAN class=265434722-10082009><FONT color=#0000ff size=2 face=Arial>Dear
Cramer,</FONT></SPAN></DIV>
<DIV><SPAN class=265434722-10082009><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=265434722-10082009><FONT color=#0000ff size=2 face=Arial>20 -
25 years ago I was re-writing the ASEAM code, and did some digging for DOE
boiler part load curves. More recently, I've used them in Energy Plus and
have shown below the values I use. No original documentation here, but
this might help...</FONT></SPAN></DIV>
<DIV><SPAN class=265434722-10082009><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=265434722-10082009><IMG
src="cid:265434722@10082009-0261"></SPAN></DIV>
<DIV><FONT color=#0000ff size=2 face=Arial></FONT> </DIV>
<DIV><SPAN class=265434722-10082009><FONT color=#0000ff size=2
face=Arial>Also, I've recently done some analysis of existing building
boiler performance and it seems that the following is true:</FONT></SPAN></DIV>
<UL>
<LI><SPAN class=265434722-10082009><FONT color=#0000ff size=2 face=Arial>Older
"high mass" / high water volume boilers (think firetube boilers and the
like) tend to have a pretty darn flat efficiency curve</FONT></SPAN></LI>
<LI><SPAN class=265434722-10082009><FONT color=#0000ff size=2 face=Arial>Newer
"low mass" / low water volume boilers show dramatically lower efficiency at
part loads, similar to the DOE curve above.</FONT></SPAN></LI></UL>
<DIV><SPAN class=265434722-10082009><FONT color=#0000ff size=2 face=Arial>If I
were modeling an older system or a new system with high water volume and good
turndown, I</FONT></SPAN><SPAN class=265434722-10082009><FONT color=#0000ff
size=2 face=Arial>'d probably use a constant efficiency "curve". Other
boilers would get a curve that resulted in low part load
efficiencies.</FONT></SPAN></DIV>
<P style="TEXT-ALIGN: center" class=MsoNormal align=center><B
style="mso-bidi-font-weight: normal"><FONT size=4>The Building Performance
Team<BR></FONT></B><B style="mso-bidi-font-weight: normal">James V. Dirkes II,
P.E., LEED AP<BR></B>1631 Acacia Drive NW<BR>Grand Rapids, MI 49504<BR>616
450 8653<?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office" /><o:p></o:p></P>
<P class=MsoNormal><o:p> </o:p></P>
<DIV> </DIV><BR>
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<FONT size=2 face=Tahoma><B>From:</B> bldg-sim-bounces@lists.onebuilding.org
[mailto:bldg-sim-bounces@lists.onebuilding.org] <B>On Behalf Of </B>Cramer
Silkworth<BR><B>Sent:</B> Monday, August 10, 2009 5:11 PM<BR><B>To:</B>
bldg-sim@lists.onebuilding.org<BR><B>Subject:</B> [Bldg-sim] boiler curves -
HIR-FPLR<BR></FONT><BR></DIV>
<DIV></DIV><FONT size=-1><FONT face="Helvetica, Arial, sans-serif">Hi
All,<BR><BR>I'm looking for some typical/default PLR efficiency curves for a
boiler for a LEED model. I'm using trnsys for the model, but I've been digging
through the DOE-2 documentation to try to find a typical default curve to use.
I've traced it to the "HIR-FPLR" keyword, but can't figure out where this
curve is actually described. Can anyone point me to where I can find the
actual equation?<BR><BR>Thanks,<BR>Cramer<BR></FONT></FONT>
<DIV class=moz-signature>-- <BR><B><FONT size=1 face=Arial>J. Cramer
Silkworth<BR>Transsolar Climate Engineering<BR>Technical consulting for energy
efficiency and environmental quality in buildings.<BR>134 Spring Street, Suite
601<BR>New York, NY 10012<BR>212-219-2255<BR><A
title=mailto:silkworth@transsolar.com
href="mailto:silkworth@transsolar.com">silkworth@transsolar.com</A>
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