<HTML><HEAD></HEAD>
<BODY dir=ltr>
<DIV dir=ltr>
<DIV style="FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: 12pt">
<DIV>If there someone can define/agree upon a solution to the ‘different weather
data used for design and simulation’ problem, we are happy to help. We
have the detailed historical data from which we can calculate the design to
numbers and we have both raw observations and localized current
conditions/forecasts plus an engine to post process this on the fly and deliver
it specific to a site. We are happy to work with anyone who wants to
tackle this.</DIV>
<DIV> </DIV>
<DIV>Chuck</DIV>
<DIV> </DIV>
<DIV
style="FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: 12pt">_____________________<BR>Chuck
Khuen<BR>Principal<BR>Weather Analytics
Inc.<BR>www.weatheranalytics.com<BR>781-856-5383</DIV>
<DIV
style="FONT-STYLE: normal; DISPLAY: inline; FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: small; FONT-WEIGHT: normal; TEXT-DECORATION: none">
<DIV style="FONT: 10pt tahoma">
<DIV> </DIV>
<DIV style="BACKGROUND: #f5f5f5">
<DIV style="font-color: black"><B>From:</B> <A title=seldomvarun@gmail.com
href="mailto:seldomvarun@gmail.com">varun kulkarni</A> </DIV>
<DIV><B>Sent:</B> Tuesday, April 05, 2011 2:42 PM</DIV>
<DIV><B>To:</B> <A title=empire999@hotmail.com
href="mailto:empire999@hotmail.com">milda margarin</A> </DIV>
<DIV><B>Cc:</B> <A title=bldg-sim@lists.onebuilding.org
href="mailto:bldg-sim@lists.onebuilding.org">bldg-sim@lists.onebuilding.org</A>
</DIV>
<DIV><B>Subject:</B> Re: [Bldg-sim] ASHRAE 90.1 Appendix
G3.1.2.2</DIV></DIV></DIV>
<DIV> </DIV></DIV>
<DIV
style="FONT-STYLE: normal; DISPLAY: inline; FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: small; FONT-WEIGHT: normal; TEXT-DECORATION: none">
<DIV>Milda,</DIV>
<DIV> </DIV>
<DIV>If you did notice, HAP uses two different weather files. one for design and
other for simulation. And if you dig into it you'll find out that they both are
different. The simulation weather is the real time (actual) temperature and
other data recorded at the airports for an extended period, which cannot be
overridden, while design weather data is based on extreme or peak weather as
defined by ASHRAE which you can change in the program.</DIV>
<DIV><BR>Now if you are looking at LEED unmet load hours they may not be
necessarily due to air sytem size, but may also be due to your plant
insufficient capacity. Download HAP e help 014 from here :<A
href="http://www.commercial.carrier.com/commercial/hvac/general/0,,CLI1_DIV12_ETI3906_MID1738,00.html">http://www.commercial.carrier.com/commercial/hvac/general/0,,CLI1_DIV12_ETI3906_MID1738,00.html</A>.</DIV>
<DIV>In here you will find a pdf saying understanding the LEED unmet load hours
in HAP.</DIV>
<DIV> </DIV>
<DIV>Simulation results is just for us to know how the building would run in
real time when sized on the design results. In simulation , HAP takes credit of
internal heat gains, which reduces your heating load, which is OK in real time.
While in design , internal heat gain is ignored in heating load calcualtions.
This is just one of the difference in simulation and design in HAP.</DIV>
<DIV> </DIV>
<DIV>I hope this helps Milda.<BR><BR><BR></DIV>
<DIV class=gmail_quote>On Tue, Apr 5, 2011 at 12:01 PM, milda margarin <SPAN
dir=ltr><<A
href="mailto:empire999@hotmail.com">empire999@hotmail.com</A>></SPAN>
wrote:<BR>
<BLOCKQUOTE
style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex"
class=gmail_quote>
<DIV>hi Varun
<DIV>
<DIV style="TEXT-INDENT: 0px !important">thanks for your reply! I have another
question though based on your statement that the system should be based on the
'design results'; I thought the whole point of using simulations is to predict
the peak capacity required and then base your design on this? (possibly by
applying safety factors according to real life experience).</DIV>
<DIV style="TEXT-INDENT: 0px !important">And how can you have unmet loads when
you design based on the peak load? In that case the 'peak load' is not the
maximum load?</DIV>
<DIV style="TEXT-INDENT: 0px !important">Further comments anybody?</DIV>
<DIV style="TEXT-INDENT: 0px !important">best regards</DIV>
<DIV style="TEXT-INDENT: 0px !important">Milda</DIV>
<DIV> </DIV>
<DIV class=hm>
<HR>
From: <A href="mailto:seldomvarun@gmail.com"
target=_blank>seldomvarun@gmail.com</A><BR>Date: Tue, 29 Mar 2011 07:51:29
-0400<BR>Subject: Re: [Bldg-sim] ASHRAE 90.1 Appendix G3.1.2.2<BR>To: <A
href="mailto:empire999@hotmail.com"
target=_blank>empire999@hotmail.com</A></DIV>
<DIV>
<DIV></DIV>
<DIV class=h5><BR><BR>
<DIV>Milda,</DIV>
<DIV>I think if you are performorming energy simulations for the baseline, it
doesnt matter what is this 25% and 15% upsizing is used for, as it used only
as much capacity it needs. And your system size should be based on the design
results and not simulation results (that also proposed model).</DIV>
<DIV>But nevertheless I always interpret this as you said in your first point,
to cover uncertainity in building simulation. </DIV>
<DIV>I also think it helps baseline to reduce its unmet load hours.</DIV>
<DIV> </DIV>
<DIV>I hope this helps.<BR><BR></DIV>
<DIV>On Tue, Mar 29, 2011 at 3:27 AM, milda margarin <SPAN dir=ltr><<A
href="mailto:empire999@hotmail.com"
target=_blank>empire999@hotmail.com</A>></SPAN> wrote:<BR>
<BLOCKQUOTE style="BORDER-LEFT: #ccc 1px solid; PADDING-LEFT: 1ex">
<DIV><SPAN
style="FONT-FAMILY: tahoma, verdana, arial, sans-serif; COLOR: rgb(42,42,42)">hi
, I already submitted this question but there were no responses so I'd like
to try again:
<DIV style="LINE-HEIGHT: 17px">could somebody share some insight to the
ASHRAE 90.1 Appendix G3.1.2.2 point regarding heating and cooling equipment
sizing based on building energy simulations. It is stated that the equipment
should be oversized by a factor of 1.25 for heating and 1.15 for cooling.
Are these "safety factors" based on the uncertainty associated with building
energy simulations or a requirement that makes sure that the system can
respond quickly enough during startup? Why are there different factors
applied for heating and cooling?</DIV>
<DIV style="LINE-HEIGHT: 17px">thanks!</DIV>
<DIV style="LINE-HEIGHT: 17px">Milda</DIV>
<DIV> </DIV></SPAN></DIV><BR>_______________________________________________<BR>Bldg-sim
mailing list<BR><A
href="http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org"
target=_blank>http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org</A><BR>To
unsubscribe from this mailing list send a blank message to <A
href="mailto:BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG"
target=_blank>BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG</A><BR><BR></BLOCKQUOTE></DIV><BR><BR
clear=all><BR>-- <BR>
<P><A name=12f26654f361a7cc_SafeHtmlFilter__MailAutoSig><SPAN><FONT
size=3><FONT face=Calibri>Thanks and Best
Regards,</FONT></FONT></SPAN></A></P>
<P><SPAN><SPAN><FONT size=3 face=Calibri></FONT></SPAN></SPAN> </P>
<P><SPAN><SPAN><FONT size=3><FONT
face=Calibri>Sincerely,</FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>Varun Kulkarni , M.S. ,
EIT</FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>RMF
Engineering</FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>5520, Research Park Drive,
Suite 300</FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>Baltimore, MD -
21228</FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3 face=Calibri></FONT></SPAN></SPAN> </P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>Office : <A
href="tel:410-576-0505" target=_blank>410-576-0505</A> ext.
5352</FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>Mobile: <A
href="tel:%28%2B1%29405-385-1928"
target=_blank>(+1)405-385-1928</A></FONT></FONT></SPAN></SPAN></P>
<P><SPAN><SPAN><FONT size=3 face=Calibri></FONT></SPAN></SPAN> </P>
<P><SPAN><SPAN><FONT size=3><FONT face=Calibri>Note: Please do not print,
unless
required.</FONT></FONT></SPAN></SPAN></P> <BR><BR></DIV></DIV></DIV></DIV></BLOCKQUOTE></DIV><BR><BR
clear=all><BR>-- <BR>
<P style="MARGIN: 0in 0in 0pt"><A name=SafeHtmlFilter__MailAutoSig><SPAN><FONT
size=3><FONT face=Calibri>Thanks and Best Regards,</FONT></FONT></SPAN></A></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3
face=Calibri></FONT></SPAN></SPAN> </P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT
face=Calibri>Sincerely,</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT face=Calibri>Varun
Kulkarni , M.S. , EIT</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT face=Calibri>RMF
Engineering</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT face=Calibri>5520,
Research Park Drive, Suite 300</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT
face=Calibri>Baltimore, MD - 21228</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3
face=Calibri></FONT></SPAN></SPAN> </P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT
face=Calibri>Office : 410-576-0505 ext. 5352</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT
face=Calibri>Mobile: (+1)405-385-1928</FONT></FONT></SPAN></SPAN></P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3
face=Calibri></FONT></SPAN></SPAN> </P>
<P style="MARGIN: 0in 0in 0pt"><SPAN><SPAN><FONT size=3><FONT face=Calibri>Note:
Please do not print, unless required.</FONT></FONT></SPAN></SPAN></P>
<P> </P><BR>
<P>
<HR>
_______________________________________________<BR>Bldg-sim mailing
list<BR>http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org<BR>To
unsubscribe from this mailing list send a blank message to
BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG<BR></DIV></DIV></DIV></BODY></HTML>