Here's some info:<br><br>
<div style="border-bottom: 1px solid rgb(153, 153, 153); position: relative; padding: 0px; background-color: transparent; width: 808px; display: none; border-top: 1px solid rgb(153, 153, 153); left: 0px;" id="nsbanner" class="d2h_main_nsbanner">
<div style="padding: 4px 10px 4px 22px; background-color: transparent; width: 100%; display: none;" id="TitleRow" class="d2h_main_titlerow">
<div style="display: none;" id="ienav" class="d2h_main_ienav">
<p class="d2h_main_linknav" align="left"> </p></div></div></div>
<div style="padding: 5px 20px 10px 22px; background-color: transparent; width: 808px; height: 654px; overflow: auto; top: 0px;" id="nstext" class="d2h_main_nstext" valign="bottom">
<div id="d2h_breadcrumbs" class="d2h_breadcrumbs"><a class="d2h_breadcrumbsNormal" href="volume2dictionary.htm">Volume 2: Dictionary</a><span class="d2h_breadcrumbsLinkSeparator"> > </span><a class="d2h_breadcrumbsNormal" href="hvaccomponents.htm">HVAC Components</a><span class="d2h_breadcrumbsLinkSeparator"> > </span><a class="d2h_breadcrumbsNormal" href="system1.htm">SYSTEM</a><span class="d2h_breadcrumbsLinkSeparator"> >
</span><a class="d2h_breadcrumbsNormal" href="airsidecontrol.htm">Airside
Control</a><span class="d2h_breadcrumbsLinkSeparator"> > </span><a class="d2h_breadcrumbsNormal" href="heatingavailabilityandsupplytemperature.htm"><font style="background-color: rgb(49, 106, 197);" color="#ffffff">Heating</font> Availability and
Supply Temperature</a></div>
<h5><font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT</font>-CONTROL</h5>
<p class="MsoBodyText">Takes a code-word that specifies how the air temperature
leaving the system <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> coil is controlled. Allowed values are: </p>
<p class="CodeWord">CONSTANT The supply air temperature is held
nearly constant at <font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT-SET-T</font>; it can change a few degrees due to fan <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heat</font> and throttling range
of the temperature controller.</p>
<p class="CodeWord">COLDEST <font style="background-color: rgb(49, 106, 197);" color="#ffffff">Sets</font> the <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> coil (hot deck)
temperature each hour to adequately <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heat</font> the zone with the lowest temperature. The limits on
the supply air temperature are governed by coil capacities, <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> schedules, and
MAX-SUPPLY-<font style="background-color: rgb(49, 106, 197);" color="#ffffff">T</font>.
WARNING: If using the COLDEST or WARMEST options in conjunction with a variable
air volume system, there are two actions within the throttling range. To reflect
reality and to prevent instability in the simulation, THROTTLING-RANGE should be
increased to 4-6F (2-3K).</p>
<p class="CodeWord">RESET Specifies use of <font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT</font>-RESET-SCH for
control of <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font>
air supply temperature based on outdoor air temperature.</p>
<p class="CodeWord">SCHEDULED Specifies use of <font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT</font>-<font style="background-color: rgb(49, 106, 197);" color="#ffffff">SET</font>-SCH for control of
<font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> air supply
temperature.</p>
<p class="MsoBodyText">In SYSTEM TYPEs VAVS, RHFS, PVAVS, and PIU the <font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT</font>-CONTROL keyword is
activated when COOL-CONTROL is <font style="background-color: rgb(49, 106, 197);" color="#ffffff">set</font> equal to WARMEST and a central <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> coil has been
specified by giving <font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT-SET-T</font> a value greater than MIN-SUPPLY-<font style="background-color: rgb(49, 106, 197);" color="#ffffff">T</font>; in this case the only
non-ignored value for <font style="background-color: rgb(49, 106, 197);" color="#ffffff">HEAT</font>-CONTROL is COLDEST. When coldest/warmest control is
specified the controller first looks to see if any ZONE has a cooling demand; if
there is a ZONE cooling demand the AHU discharge temperature is reset to attempt
to just satisfy the ZONE with the largest cooling demand. If no ZONE has a
cooling demand the controller looks to satisfy the ZONE with the greatest <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> demand but
without forcing any ZONE into creating a cooling demand. If neither a <font style="background-color: rgb(49, 106, 197);" color="#ffffff">heating</font> or cooling demand
is found for any ZONE mixed air is passed.</p></div><br><br><div class="gmail_quote">On Fri, Nov 12, 2010 at 3:33 PM, Katherine Louman-Gardiner <span dir="ltr"><<a href="mailto:klgardiner@flowgroup.ca">klgardiner@flowgroup.ca</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div link="blue" vlink="purple" lang="EN-CA">
<div>
<p class="MsoNormal">Hi All,</p>
<p class="MsoNormal">My boss wants me to model a large AHU as a space by
itself. Our client is running the heating loop at night (when it’s
below 40F), despite the fans being off. There is also a very leaky damper
allowing fresh air in to the space. (I’ve got no cooling, and a fan
mimicking the leaky damper). It’s a wasteful practice, but we’re
trying to quantify How wasteful it is.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">My question is:</p>
<p class="MsoNormal">Is there a way to have the heating turn on/off based on an
outdoor temperature?</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Since I couldn’t find a way, I created a dummy zone
with only ventilation and no heating – but I still couldn’t figure
out a way to use the temperature in the dummy zone to control the main
zone. The only way I could think of was Pkgd Single Zone, but that
added cooling and a condenser that I couldn’t get rid of.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Anyway, Thanks for the help. If I’m going about
this the wrong way, I’d appreciate any feedback.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Thank you. </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"><span style="font-size: 9pt; color: navy;">Katherine Louman-Gardiner, EIT</span></p>
<p class="MsoNormal"><span style="font-size: 9pt; color: navy;">Mechanical Engineer<br>
</span><span style="font-size: 9pt;"><br>
<br>
</span></p>
<p class="MsoNormal"> </p>
</div>
</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">BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG</a><br>
<br></blockquote></div><br><br clear="all"><br>-- <br>Carol Gardner PE<br>
<div style="visibility: hidden; left: -5000px;" id="avg_ls_inline_popup"></div><style type="text/css">#avg_ls_inline_popup{position: absolute;z-index: 9999;padding: 0px 0px;margin-left: 0px;margin-top: 0px;overflow: hidden;word-wrap: break-word;color: black;font-size: 10px;text-align: left;line-height: 130%;}</style>