[bldg-sim] Glycol Chillers/Pacakge units..

Brandon Nichols BrandonN at Hargis.biz
Tue Jan 23 13:29:36 PST 2007


Hi John,
 
Isn't it "simply" a matter of the derating coil heat transfer and
pumping efficiencies, based on the percentage of glycol concentration?
Of course, deriving the derating factors is the not so simple part...
and probably the general solution would be to define a parametric
relationship between the glycol concentration and the coil and pumping
efficiencies.
 
Glycol manufacturer's data should have plenty of info on the derating
factors, perhaps even a parametric equation that can be utilized in BDL.
 
Well that was the easy part... hope it helps!
 
Brandon Nichols, PE
Mechanical
HARGIS ENGINEERS
600 Stewart St
Suite 1000
Seattle, WA 98101
d | 206.436.0400 c | 206.228.8707
o | 206.448.3376 f | 206.448.4450
www.hargis.biz


  _____  

From: bldg-sim at gard.com [mailto:bldg-sim at gard.com] On Behalf Of Aulbach,
John
Sent: Tuesday, January 23, 2007 11:12 AM
To: bldg-sim at gard.com
Subject: [bldg-sim] Glycol Chillers/Pacakge units..


Hi Folks:
 
I am running into a few office/data center buildings where the main
office areas are cooled by conventional chillers and the data
center/server areas are conditioned by either Liebert type package units
or 40% glycol-to-water mix chillers (colder climates that still need
servers cooled). Naturally, both units will be on the same electric
meter.
 
The standard DOE-2 does not model glycol cooling, and a commercial
building does not need the refrigeration version of eQuest.  Usually, I
know the kw/ton (or the moral equivalent) of the glycol cooling source.
But glycol/water does not have the same heat absorption properties as
straight shot water to follow the load.
 
I am trying to insure I am showing the correct energy used by these
units, as I believe the LEED now includes the process loads within the
Base and Proposed models to certify the level of LEED obtained.
 
Does anyone have any "tricks" they have used?
 
John R. Aulbach, PE, CEM
Project Manager
Nexant, Inc.
100 North Barranca, Suite 820
West Covina, CA 91791 USA
Phone: 626-430-9054
Fax: 626-430-9060
email: jaulbach at nexant.com
 

==================
You received this e-mail because you are subscribed 
to the BLDG-SIM at GARD.COM mailing list.  To unsubscribe 
from this mailing list send a blank message to 
BLDG-SIM-UNSUBSCRIBE at GARD.COM


===========================
You received this e-mail because you are subscribed 
to the BLDG-SIM at GARD.COM mailing list.  To unsubscribe 
from this mailing list send a blank message to 
BLDG-SIM-UNSUBSCRIBE at GARD.COM
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20070123/100df53e/attachment-0002.htm>


More information about the Bldg-sim mailing list