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<font style="FONT-SIZE: 10pt; FONT-FAMILY: tahoma"> <h5 style="MARGIN: auto
0in"><span style="FONT-WEIGHT: normal"><font face="Times New Roman">I had a
similar error recently and adjusted LOOP-SIZE-RATIO on the Basic
Specifications tab for the loop</font></span> </h5> <h5 style="MARGIN: auto
0in"><span style="FONT-WEIGHT: normal"><font face="Times New Roman"></font>
</span> </h5> <h5 style="MARGIN: auto 0in"><span style="FONT-WEIGHT:
normal"><font face="Times New Roman">LOOP-SIZE-RATIO</font></span> </h5>
<div style="MARGIN: auto 0in"><span style="FONT-SIZE: 10pt"><font
face="Times New Roman">The safety factor for loop sizing. (Note that safety
factors could have already been specified within the secondary HVAC systems
attached to this loop). This keyword is used only when SIZING-OPTION =
SECONDARY-EQUIP; it is ignored for the PRIMARY-EQUIP sizing method. When
primary equipment is to be auto-sized by the program, this keyword modifies
the default capacity assigned. Note that this keyword affects only the
auto-sizing of the primary equipment based on secondary loop loads. It has
no effect on the design loop flow; the loop flow is based on the sum
of the coil flows or other loads attached to the loop. However, the design
pump flow can be modified via keywords in the PUMP command.</font></span>
</div> <div> <br /> </div></font> <br /> <blockquote
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT:
#000000 2px solid; MARGIN-RIGHT: 0px">-----Original Message----- <br />
From: "James Hansen" <JHANSEN@ghtltd.com> <br />To: "Josh Doherty"
<jdoherty@dcengineering.net> <br />Cc:
equest-users@lists.onebuilding.org <br />Date: Wed, 6 May 2009 14:15:04
-0400 <br />Subject: Re: [Equest-users] Hot water loop demand and boiler
sizing <br /> <br /> <div class="Section1"> <div><span
style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri','sans-serif'">
I constantly struggle with the same issue (loop sizing) and whether or not
it is actually having an impact on energy consumption.</span> </div>
<div><span style="FONT-SIZE: 11pt; COLOR: #1f497d; FONT-FAMILY:
'Calibri','sans-serif'">In a recent project I did, I had the same results as
you. However, I went to the hour-by-hour report page for the plant,
and using your example below: I would get something like -2992234 buth
at 8am, -1000000 at 9am, -2900000 buth at 10am, etc.. The heating load
was bouncing high and low, meaning the loop had to be sized for -2992234 but
the actual maximum heating load that your system would see in actual
operation was closer to the average of these two “bouncing” numbers (ie
-2000000 in your case).</span> </div> <div><span style="FONT-SIZE:
11pt; COLOR: #1f497d; FONT-FAMILY: 'Calibri','sans-serif'">Never figured out
why, and posted a question here and received no answers. Stepped
utility block was 15 mins, didn’t have any weird temperature setpoints,
etc.</span> </div> <div><span style="FONT-SIZE: 11pt; COLOR:
#1f497d; FONT-FAMILY: 'Calibri','sans-serif'">Ultimately I don’t think
these warning messages are too concerning, but I also know NEVER to use
eQuest to do my load calcs for maximum heating/cooling equipment
sizing.</span> </div> <div> <div><b><span style="COLOR: teal;
FONT-FAMILY: 'Arial','sans-serif'">GHT Limited <br /></span></b><b>
<span style="FONT-SIZE: 11pt; FONT-FAMILY: 'Arial','sans-serif'">James
Hansen</span></b><b><span style="COLOR: black">, PE, LEED AP</span></b>
</div> <div><b><span style="FONT-SIZE: 10pt; COLOR: black;
FONT-FAMILY: 'Arial','sans-serif'">Senior Associate</span></b> </div>
<div><span style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Arial','sans-serif'">
1010 N. Glebe Rd, Suite 200</span> </div> <div><span
style="FONT-SIZE: 7.5pt; FONT-FAMILY: 'Arial','sans-serif'">Arlington, VA
22201-4749</span> </div> <div><span style="FONT-SIZE: 7.5pt;
COLOR: black; FONT-FAMILY: 'Arial','sans-serif'">703-338-5754 (Cell)</span>
</div> <div><span style="FONT-SIZE: 7.5pt; COLOR: black;
FONT-FAMILY: 'Arial','sans-serif'">703-243-1200 (Office)</span> </div>
<div><span style="FONT-SIZE: 7.5pt; COLOR: black; FONT-FAMILY:
'Arial','sans-serif'">703-276-1376 (Fax)</span> </div> </div>
<div><span style="FONT-SIZE: 11pt; COLOR: teal; FONT-FAMILY:
'Arial','sans-serif'"><a href="http://www.ghtltd.com/"><span
style="FONT-SIZE: 10pt">www.ghtltd.com</span></a></span> </div> <div>
<div style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in;
BORDER-TOP: #b5c4df 1pt solid; PADDING-LEFT: 0in; PADDING-BOTTOM: 0in;
BORDER-LEFT: medium none; PADDING-TOP: 3pt; BORDER-BOTTOM: medium none">
<div><b><span style="FONT-SIZE: 10pt; FONT-FAMILY:
'Tahoma','sans-serif'">From:</span></b><span style="FONT-SIZE: 10pt;
FONT-FAMILY: 'Tahoma','sans-serif'">
equest-users-bounces@lists.onebuilding.org
[mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Josh
Doherty <br /><b>Sent:</b> Wednesday, May 06, 2009 2:07 PM
<br /><b>To:</b> equest-users@lists.onebuilding.org <br /><b>
Subject:</b> [Equest-users] Hot water loop demand and boiler sizing</span>
</div> </div> </div> <div><span style="FONT-SIZE: 10pt;
FONT-FAMILY: 'Arial','sans-serif'">Energy Modelers,</span> </div>
<div><span style="FONT-SIZE: 10pt; FONT-FAMILY: 'Arial','sans-serif'">I am
getting the following warning message when I type in the actual boiler
capacity:</span> </div> <div><span style="FONT-SIZE: 10pt;
FONT-FAMILY: 'Arial','sans-serif'"> </span> </div> <div><b>
<span style="FONT-SIZE: 10pt; FONT-FAMILY: 'Arial','sans-serif'">“Hot
Water Loop: the heating capacity is smaller than the secondary
demand. Primary = -2000000 and Secondary = -2992234.”</span></b>
</div> <div><span style="FONT-SIZE: 10pt; FONT-FAMILY:
'Arial','sans-serif'"> </span> </div> <div><span
style="FONT-SIZE: 10pt; FONT-FAMILY: 'Arial','sans-serif'">If I let eQuest
size the boilers, everything is fine…so I know it has to do with me
putting in the actual boiler capacity for the proposed design.
However, the issue here is there is no way the max heating demand is almost
-3.0 MBh as it states in the warning message. I can not figure out
where eQuest is getting this number; especially since the SS-D report (which
should tell me the absolute max load demand on the building HVAC system –
including outside air) says the maximum heating load is -1035.026 MBh.
Can anyone please help me determine why I am getting this error, where the
-2992234 number is coming from, and if the SS-D report really is the actual
maximum HVAC load demand? Thanks everyone for their help. Your time is
very much appreciated.</span> </div> <div><span style="FONT-SIZE:
10pt; FONT-FAMILY: 'Arial','sans-serif'"> </span> </div> <div>
<strong>Josh Doherty</strong> </div> <div><span style="FONT-SIZE:
10pt; FONT-FAMILY: 'Arial','sans-serif'"> </span> </div> <div>
</div> <div> </div> <div> </div>
<div> </div> </div> </blockquote>
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