<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:10pt"><div>Brad:<br><br>Sorry, I have not submitted a project with PTAC units to LEED yet. I am modeling two buildings right now that use a VRV system with a DOAS that supplies ventilation air directly to the space. One is a commercial property in Middletown, CT and the other is a high rise residential in Waterbury, CT.<br><br>I am preparing an requested for an official interpretation of this section to ASHRAE right now.<br><br>I think it takes several months to receive an answer. I will post the answer on the forum once I receive it.<br><br>Paul Diglio<br></div><div style="font-family: times new roman,new york,times,serif; font-size: 10pt;"><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><font face="Tahoma" size="2"><hr size="1"><b><span
style="font-weight: bold;">From:</span></b> Brad L. Huff <BradH@BVHis.com><br><b><span style="font-weight: bold;">To:</span></b> Paul Diglio <paul.diglio@sbcglobal.net><br><b><span style="font-weight: bold;">Cc:</span></b> "equest-users@lists.onebuilding.org" <equest-users@lists.onebuilding.org><br><b><span style="font-weight: bold;">Sent:</span></b> Fri, June 10, 2011 11:50:27 AM<br><b><span style="font-weight: bold;">Subject:</span></b> RE: [Equest-users] 2007 90.1 Appendix G3.1.2.4<br></font><br>
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--></style><div class="WordSection1"><p class="MsoNormal"><span style="font-size: 10pt;">Paul:</span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 10pt;">The message I wanted to post originally is pasted below. I should go on to further state that the PTAC units are naturally ventilated spaces. In your experience with these systems did you model them as operating 24/7 and if you did, did problems arise from a LEED review?</span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span
style="font-size: 10pt;"> </span></p><p class="MsoNormal"><span style="font-size: 8pt;">Modelers,</span></p><p class="MsoNormal"><span style="font-size: 8pt;"> </span></p><p class="MsoNormal"><span style="font-size: 8pt;">I apologize for the blank email I previously sent, I meant to hit save, not send (Paul was quick to respond, thank you). I am modeling a dormitory of System Type 1. Appendix G Section G3.1.2.4 states, “Supply and return fans shall operate continuously whenever spaces are occupied and shall be cycled to meet heating and cooling loads during unoccupied hours.” If the building occupancy schedule is fractionally loaded 24/7, am I over exaggerating fan energy consumption of the PTAC units by operating the fans continuously 24/7? Has anyone received review comments from LEED on the issue? </span></p><p class="MsoNormal"><span style="font-size: 8pt;"> </span></p><p class="MsoNormal"><span style="font-size: 8pt;">Thank
you,</span></p><p class="MsoNormal"><span style="font-size: 8pt;">Brad</span></p><p class="MsoNormal"><span style="font-size: 10pt; color: rgb(31, 73, 125);"> </span></p><p class="MsoNormal"><span style="font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p><div><p class="MsoNormal" style=""><b><span style="font-size: 8.5pt; color: gray;">Brad Huff, E.I.T., LEED Green Associate, Mechanical Engineer</span></b><span style="font-size: 8pt; color: navy;"> </span><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);">I BVH Integrated Services I</span></b><b><span style="font-size: 8.5pt; color: black;"> </span></b><b><span style="font-size: 8.5pt; color: gray;">860.286.9171 tel </span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);">I</span></b><b><span style="font-size: 8.5pt; color: gray;"> 860.242.0236 fax</span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);"> I</span></b><b><span
style="font-size: 8.5pt; color: gray;"> 50 Griffin Road South, Bloomfield CT 06002 </span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);">I <a rel="nofollow" target="_blank" href="http://www.bvhis.com/" title="http://www.bvhis.com/"><span style="font-weight: normal;">.bvhis.com</span></a> I</span></b><b><span style="font-size: 10pt; color: gray;"> </span></b><b><span style="font-size: 8.5pt; color: gray;"><a target="_blank" href="http://twitter.com/bvhis">twitter.com/bvhis</a></span></b><b><span style="font-size: 10pt; color: gray;"> </span></b><b><span style="font-size: 8pt; color: rgb(0, 0, 160);">I Hartford Boston </span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);"></span></b></p><p class="MsoNormal" style=""><span style="font-family: "sans-serif"; color: navy;"> </span></p></div><p class="MsoNormal"><span style="font-family: "sans-serif"; color: rgb(31, 73, 125);">
</span></p><div><div style="border-width: 1pt medium medium; border-style: solid none none; border-color: rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color; padding: 3pt 0in 0in;"><p class="MsoNormal"><b><span style="font-size: 10pt; font-family: "sans-serif";">From:</span></b><span style="font-size: 10pt; font-family: "sans-serif";"> Paul Diglio [mailto:paul.diglio@sbcglobal.net] <br><b>Sent:</b> Friday, June 10, 2011 11:06 AM<br><b>To:</b> Brad L. Huff; equest-users@lists.onebuilding.org<br><b>Cc:</b> Jason Glazer<br><b>Subject:</b> Re: [Equest-users] 2007 90.1 Appendix G3.1.2.4</span></p></div></div><p class="MsoNormal"> </p><div><p class="MsoNormal"><span style="font-size: 10pt;">Brad:<br><br>Did you intended to post a message?<br><br>G3.1.2.4 is unclear. First it states that the supply fan shall run continuously during the occupied hours and shall be cycled to meet heating and cooling loads during
unoccupied hours. Ok , I get that.<br><br>Then it states that if the supply fan is modeled as cycling and the fan energy is included in the EER, then the fan energy shall not be modeled explicitly. That is confusing. When is it permissible to model the supply fan as cycling. Is AHSRAE talking a supply fan serving a space that is never occupied? Obviously, there is no such thing, someone will sometime do something in the room.<br><br>Then G3.1.2.4 goes on to state that the supply, return or exhaust fans will remain on during occupied and unoccupied hours in spaces that have heath and safety mandated minimum ventilation requirements during unoccupied hours.<br><br>This requirement does not cover many of the scenarios that I model. For example, natural ventilation provided by operable windows. It does not make sense to keep the fan running if it not supplying ventilation air. I am presently modeling a
residential high-rise. No one keeps their apartment supply fan running 24X7. Especially if there are operable windows.<br><br>Another example is a commercial property that has a DOAS supplying minimum air directly to the zone HVAC system or supplying minimum directly to the zone without isolation dampers. If I supply the 62.1 minimum air required by the DOAS, then why run the supply fan?<br><br>I would be interested to hear other interpretations. Perhaps Jason Glazer can give us his unofficial opinion.<br><br>Paul Diglio</span></p><div><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p></div><div><p class="MsoNormal"><span style="font-size: 10pt;"> </span></p><div><div class="MsoNormal" style="text-align: center;" align="center"><span style="font-size: 10pt; font-family: "sans-serif";"><hr align="center" width="100%" size="1"></span></div><p class="MsoNormal" style="margin-bottom:
12pt;"><b><span style="font-size: 10pt; font-family: "sans-serif";">From:</span></b><span style="font-size: 10pt; font-family: "sans-serif";"> Brad L. Huff <BradH@BVHis.com><br><b>To:</b> "equest-users@lists.onebuilding.org" <equest-users@lists.onebuilding.org><br><b>Sent:</b> Fri, June 10, 2011 10:10:50 AM<br><b>Subject:</b> [Equest-users] 2007 90.1 Appendix G3.1.2.4</span><span style="font-size: 12pt; font-family: "serif";"></span></p><div><p class="MsoNormal">Modelers,</p><p class="MsoNormal"> </p><p class="MsoNormal"><b><span style="font-size: 8.5pt; color: gray;">Brad Huff, E.I.T., LEED Green Associate, Mechanical Engineer</span></b><span style="font-size: 8pt; color: navy;"> </span><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);">I BVH Integrated Services I</span></b><b><span style="font-size: 8.5pt; color: black;"> </span></b><b><span style="font-size: 8.5pt; color: gray;">860.286.9171
tel </span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);">I</span></b><b><span style="font-size: 8.5pt; color: gray;"> 860.242.0236 fax</span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);"> I</span></b><b><span style="font-size: 8.5pt; color: gray;"> 50 Griffin Road South, Bloomfield CT 06002 </span></b><b><span style="font-size: 8.5pt; color: rgb(0, 0, 160);">I <a rel="nofollow" target="_blank" href="http://www.bvhis.com/" title="http://www.bvhis.com/"><span style="font-weight: normal;">.bvhis.com</span></a> I</span></b><b><span style="font-size: 10pt; color: gray;"> </span></b><b><span style="font-size: 8.5pt; color: gray;"><a rel="nofollow" target="_blank" href="http://twitter.com/bvhis">twitter.com/bvhis</a></span></b><b><span style="font-size: 10pt; color: gray;"> </span></b><b><span style="font-size: 8pt;">I Hartford Boston </span></b></p><p class="MsoNormal"><span style="color:
navy;"> </span></p><p class="MsoNormal"> </p></div></div></div></div></div></div></div>
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