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<DIV dir=ltr align=left><SPAN class=904103414-19052010><FONT color=#0000ff
size=2 face=Arial>Rob,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=904103414-19052010><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=904103414-19052010><FONT color=#0000ff
size=2 face=Arial>I have a number of questions:</FONT></SPAN></DIV>
<OL dir=ltr>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>Do you have many lab hoods? And are exhaust and make-up air
revised for the lab hoods at the night set back time?</FONT></SPAN></DIV></LI>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>What is the percent of outside air to the lab? Does this
percentage change during the night set back time?</FONT></SPAN></DIV></LI>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>Do you have a pre-heat or exhaust heat recovery and
pre-cooling on your make-up air? What is the temperature setting of
this pre-heat or heat recovery and pre-cooling? Does the temperature
settings on these change at the night set back
time?</FONT></SPAN></DIV></LI>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>Do you utilize an air or water side economizer for 1st stage
cooling? Does this use change any at night set back
time?</FONT></SPAN></DIV></LI>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>Does the fan run continuously day and night? Have you ran
models with the fan running continuously, and with fan cycling based on demand
at night and off completely at night, to see how the results
compare?</FONT></SPAN></DIV></LI>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>Do you have a internal load watts per square foot and latent
load on the space from interior lighting and equipment? Do these
loads change at the night set back time?</FONT></SPAN></DIV></LI>
<LI>
<DIV align=left><SPAN class=904103414-19052010><FONT color=#0000ff size=2
face=Arial>Are you adding humidification or dehumidifying the space based on
some humidity settings? Does the humidity settings change during the
night set back time?</FONT></SPAN></DIV></LI></OL>
<DIV><SPAN class=904103414-19052010></SPAN><FONT face=Arial><FONT
color=#0000ff><FONT
size=2>One of these things is probably causing the increased chilled water cooling load. Often if you have high internal loads, even at night, then changes to the fan cycling and the amount of outside air brought in<SPAN
class=904103414-19052010> at
night,</SPAN> will increase the chilled water cooling load. I would review all of these areas and run various test models to see how they each affect your energy usage when modified.</FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT
size=2></FONT></FONT></FONT> </DIV>
<DIV><FONT color=#0000ff size=2 face=Arial><SPAN class=904103414-19052010>Our
firm just completed modeling some very large lab facilities with more than 55
exhaust hoods in the building, with high internal loads 24/7 and 100%
outside air. As long as the models are set up correctly they are normally
right. It takes some real design and thermal dynamic thought and often may
models to really get your mind right with what is truly going on with the
facility. Its important to keep an open mind to what is going on.
Having been doing computer hourly modeling for over 17 years, it is often easy
to think you have a handle on what is going on with the building, but it is
important to keep an open mind and investigate all the different avenues that
you can think of until figure out what is going on. I have 99% of the time
that I have blamed the screwy program having problems that I have found that I
just didn't look at all the different angles enough.</SPAN></FONT></DIV>
<DIV><FONT color=#0000ff size=2 face=Arial><SPAN
class=904103414-19052010></SPAN></FONT> </DIV>
<DIV><FONT color=#0000ff size=2 face=Arial><SPAN class=904103414-19052010>
<DIV align=left>
<DIV align=left><STRONG><EM><FONT color=#0000ff size=6
face="Bradley Hand ITC">David A. Bastow </FONT></EM></STRONG></DIV>
<DIV align=left><STRONG><EM><FONT face="Rockwell Extra Bold">McClure
Engineering, Inc. </FONT></EM></STRONG></DIV>
<DIV align=left><FONT face=Batang><A title=http://www.mcclure-engineering.com/
href="http://www.mcclure-engineering.com/"><FONT
title=http://www.mcclure-engineering.com/ color=#0000ff size=2
face=Arial></FONT></A></FONT> </DIV></DIV></SPAN></FONT></DIV>
<DIV><BR></DIV>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> equest-users-bounces@lists.onebuilding.org
[mailto:equest-users-bounces@lists.onebuilding.org] <B>On Behalf Of </B>Rob
Hudson<BR><B>Sent:</B> Wednesday, May 19, 2010 7:46 AM<BR><B>To:</B>
equest-users@lists.onebuilding.org<BR><B>Subject:</B> [Equest-users] T-Stat is
acting Screwy<BR></FONT><BR></DIV>
<DIV></DIV>I have a lab space that is kept between 73 and 70 degrees all year
long. One of my parametric runs has the cooling and heating T-stat
schedules changing to have night time setbacks to 80 and 60, respectively.
When i use these, i get more energy spent overall. specifically, i have a
chilled water meter, steam meter, electric meter and hot water meter to monitor
everything. The chilled water increases while the others slightly decrease
when i use the set back schedules. Any ideas?<BR clear=all><BR>-- <BR>Rob
Hudson<BR></BODY></HTML>