<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><DIV>Jim:</DIV>
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<DIV>I don't have the reference right in front of me, but I believe the ASHRAE HVAC Systems has a table for useful life. Also the California Energy Commission. But my references are at work. Reemail me at <A href="mailto:jaulbach@ptrenergy.com">jaulbach@ptrenergy.com</A> to remind me, and I shall look them up for you.</DIV>
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<DIV>John Aulbach<BR></DIV>
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<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Jin Minming <jminming@yahoo.com><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> bldg-sim@lists.onebuilding.org<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Mon, February 15, 2010 3:42:12 AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> [Bldg-sim] How to estimate performance of HVAC system in life cycle analysis?<BR></FONT><BR>
<DIV style="FONT-FAMILY: times new roman, new york, times, serif; FONT-SIZE: 12pt">Hello all,<BR>
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<DIV><BR>In life cycle analysis of buildings, it seems it is very hard to estimate long-term performance of HVAC systems (or other building components), for example, air handling units, chiller, or boilers. It makes sense that HVAC system will degrade with time, depending on many factors, like maintainence, wear-and-tear. The problem is how to quantify these change with time. Maybe some probabilstic or scenario methods can be used. Would you please tell me the common method to predict these performance change or where I can find some good references about this topic?<BR><BR>Thanks,<BR><BR>Jim Terrry <EM></EM><BR></DIV></DIV><BR></DIV></DIV></DIV><BR></DIV></DIV></div><br>
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