[Equest-users] Oversized cooling

Joe Huang yjhuang at whiteboxtechnologies.com
Mon Dec 1 16:36:34 PST 2014


So the LS-C peak load is actually even lower than on the SS-D.  This 
will take more investigation.  Could you send the BDL file to me?  I 
won't get to it till the weekend, though.

Joe

  On 12/1/2014 4:00 PM, Gonzalo Lema wrote:
>
> Joe,
>
> Thanks again for your help
>
> The Peak cooling load is 68 tons :
>
> So I still don’t get why the cooling capacity is 629 tons
>
> *SUMAC*
>
> *Gonzalo Lema | Mechanical Engineer | LEED GA*
>
> Tel: +1.773.857.7906 Ext 7009 (Chicago, USA)
>
> Tel: +1.305.814.8805 (Miami, USA)
>
> Tel: +511.253.5355 (Lima, Perú)
>
> Tel: +593.4.600.0613 (Guayaquil, Ecuador)
> Tel: + 571.3151985 (Bogotá, Colombia)
>
> glema at sumacinc.com <mailto:glema at sumacinc.com>
>
> www.sumacinc.com <http://www.sumacinc.com/>
>
> *From:*Joe Huang [mailto:yjhuang at whiteboxtechnologies.com]
> *Sent:* Monday, December 01, 2014 5:43 PM
> *To:* Gonzalo Lema
> *Cc:* equest-users at lists.onebuilding.org
> *Subject:* Re: [Equest-users] Oversized cooling
>
> Gonzalo,
>
> The answer to your question, I believe, lies in the
>
> second longer part of my answer, i.e., the difference
>
> between LOADS loads at a fixed reference temperature
>
> and no OA and the SYSTEM loads at the actual room temperature
>
> with those factors taken into account. For the mild California
>
> climate that you simulated, these effects are quite considerable.
>
> Without sounding like a nag, please look at the LOADS report
>
> for the peak cooling load.
>
>
>
> Everyone should be duly impressed that this reply is being sent by IPhone
>
> from a hotel lobby in Shanghai China...
>
>
> Sent from my iPhone
>
> Joe Huang
>
> White Box Technologies
>
> 346 Rheem Blvd Suite 108D
>
> Moraga CA 94556
>
> (o) 1(925)388-0265
>
> (c) 1(510)928-2683
>
> yjhuang at whiteboxtechnologies.com <mailto:yjhuang at whiteboxtechnologies.com>
>
>
> On Dec 1, 2014, at 11:29 PM, Gonzalo Lema <GLema at sumacinc.com 
> <mailto:GLema at sumacinc.com>> wrote:
>
>     Hi Joe,
>
>     I also believe that the fan size is probably determined by the
>     maximum heating, not the cooling, load. However, I don’t
>     understand why after determining the airflow, it doesn’t adjust
>     the cooling coil to have a similar capacity as the building HVAC
>     maximum cooling load (SS-D report).
>
>     Would you like to see the input/output files?
>
>     Thanks for your help
>
>     *SUMAC*
>
>     *Gonzalo Lema | Mechanical Engineer | LEED GA*
>
>     Tel: +1.773.857.7906 Ext 7009 (Chicago, USA)
>
>     Tel: +1.305.814.8805 (Miami, USA)
>
>     Tel: +511.253.5355 (Lima, Perú)
>
>     Tel: +593.4.600.0613 (Guayaquil, Ecuador)
>     Tel: + 571.3151985 (Bogotá, Colombia)
>
>     glema at sumacinc.com <mailto:glema at sumacinc.com>
>
>     www.sumacinc.com <http://www.sumacinc.com/>
>
>     *From:* Equest-users
>     [mailto:equest-users-bounces at lists.onebuilding.org] *On Behalf Of
>     *Joe Huang
>     *Sent:* Wednesday, November 26, 2014 3:05 PM
>     *To:* equest-users at lists.onebuilding.org
>     <mailto:equest-users at lists.onebuilding.org>
>     *Subject:* Re: [Equest-users] Oversized cooling
>
>     Without looking at the DOE-2.2 input and output files, it's
>     difficult to give you a definitive answer, but from my experience
>     explanations for such sizing questions can always be found with a
>     little digging and understanding of how DOE-2 does autosizing.
>
>     When DOE-2 does autosizing, it takes the maximum loads reported
>     from LOADS and calculates the equipment capacity (heating,
>     cooling, and fan) needed to meet those loads. The fact that the
>     building is in a cool climate (Colorado Springs) has  several
>     implications on the sizing calculation - (1) fan size is probably
>     determined by the maximum heating, not the cooling, load, (2) fan
>     size will also be increased significantly (1.24) due to the
>     altitude, (3) substantial difference between the peak cooling load
>     from LOADS and SYSTEMS, since the former is derived at a constant
>     reference temperature with no outside air, while the latter is
>     derived at the actual zone temperature and with outside air (e.g.,
>     economizer running earlier in the day, etc.).   To trace these
>     differences, compare the peak loads in the LOADS reports to those
>     in the SYSTEM reports.
>
>     Joe
>
>     Joe Huang
>     White Box Technologies, Inc.
>     346 Rheem Blvd., Suite 205A
>     Moraga CA 94556
>     yjhuang at whiteboxtechnologies.com
>     <mailto:yjhuang at whiteboxtechnologies.com>
>     http://weather.whiteboxtechnologies.com for simulation-ready
>     weather data
>     http://www.whiteboxtechnologies.com
>     (o) (925)388-0265
>     (c) (510)928-2683
>     "building energy simulations at your fingertips"
>
>
>     On 11/25/2014 11:18 AM, Sami, Vikram wrote:
>
>         Curious.
>
>         I do think the higher load seems to be more like what you
>         should expect for a building this size (7501 kBTU/h = 625
>         tons. For a 102,000 ft2 building that’s 163 ft2/ton). That
>         might be slightly oversized for Ft Carson, although Colorado
>         springs gets hot in the summer. Not sure what your building
>         loads are, but 163 ft2/ton is not unheard of for a heavy use
>         building. I would expect something more in the range of
>         250-300. So the question is why is the maximum cooling load
>         reporting as only 927 kBTU/hr (77.25 tons = 1320 ft2/ton)
>
>         Just my two cents from looking at this for five minutes – I
>         might be wrong.
>
>         *Vikram Sami*
>         BEMP, LEED BD+C
>         Associate Partner
>
>         	
>
>         	
>
>         ZGF ARCHITECTS LLP
>         *T *206.521.3509 *E *vikram.sami at zgf.com
>         <mailto:vikram.sami at zgf.com>
>         925 Fourth Avenue, Suite 2400
>         Seattle, WA 98104
>
>         *From:* Equest-users
>         [mailto:equest-users-bounces at lists.onebuilding.org] *On Behalf
>         Of *Gonzalo Lema
>         *Sent:* Monday, November 24, 2014 12:25 PM
>         *To:* equest-users at lists.onebuilding.org
>         <mailto:equest-users at lists.onebuilding.org>
>         *Subject:* [Equest-users] Oversized cooling
>
>         Hi,
>
>         I have a problem with the cooling capacity. The Max cooling
>         load is 927 kbtu/hr, but the cooling capacity is 7501 kbtu/h.
>         I auto-sized the equipment (system and cooling coil) for 1.00,
>         but I don’t understand why the factor seems to be 8x.
>
>         <image001.jpg>
>
>         <image002.png>
>
>         The system fan Works in part-load 0-20% all the time:
>
>         <image003.png>
>
>         Does anybody knows what could be causing this?
>
>         **
>
>         Thanks.
>
>         **
>
>         *SUMAC*
>
>         *Gonzalo Lema | Mechanical Engineer | LEED GA*
>
>         Tel: +1.773.857.7906 Ext 7009 (Chicago, USA)
>
>         Tel: +1.305.814.8805 (Miami, USA)
>
>         Tel: +511.253.5355 (Lima, Perú)
>
>         Tel: +593.4.600.0613 (Guayaquil, Ecuador)
>         Tel: + 571.3151985 (Bogotá, Colombia)
>
>         glema at sumacinc.com <mailto:glema at sumacinc.com>
>
>         www.sumacinc.com <http://www.sumacinc.com/>
>
>         *From:* Dante Garcia
>         *Sent:* Monday, November 24, 2014 10:24 AM
>         *To:* Gonzalo Lema
>         *Subject:* RE: eQuest - Fort Cartson
>
>         Hola Gonzalo, no he podido encontrar el error hasta el viernes
>         que estuve avanzando.
>
>         Ahora he estado con otras prioridades, mañana puedo volver a
>         revisar el proyecto.
>
>         Saludos,
>
>         Dante
>
>         *SUMAC*
>
>         *Dante Garcia, LEED AP BD+C | Analista LEED Energía*
>
>         Tel: +511.253.5355 Anexo 16 (Lima, Perú)
>
>         Cel: +51.989.685.769 (Lima, Perú)
>
>         Tel: +593.4.600.0613 (Guayaquil, Ecuador)
>         Tel: + 571.3151985 (Bogotá, Colombia)
>
>         Tel: +1.773.857.7906 (Chicago, USA)
>
>         dgarcia at sumacinc.com <mailto:dgarcia at sumacinc.com>
>
>         www.sumacinc.com <http://www.sumacinc.com/>
>
>         *De:*Gonzalo Lema
>         *Enviado el:* lunes, 24 de noviembre de 2014 11:17 a.m.
>         *Para:* Dante Garcia
>         *Asunto:* RE: eQuest - Fort Cartson
>
>         Buen día,
>
>         ¿Alguna novedad?
>
>         Yo sigo revisando también.
>
>         Saludos
>
>         *SUMAC*
>
>         *Gonzalo Lema | Mechanical Engineer | LEED GA*
>
>         Tel: +1.773.857.7906 Ext 7009 (Chicago, USA)
>
>         Tel: +1.305.814.8805 (Miami, USA)
>
>         Tel: +511.253.5355 (Lima, Perú)
>
>         Tel: +593.4.600.0613 (Guayaquil, Ecuador)
>         Tel: + 571.3151985 (Bogotá, Colombia)
>
>         glema at sumacinc.com <mailto:glema at sumacinc.com>
>
>         www.sumacinc.com <http://www.sumacinc.com/>
>
>         *From:* Gonzalo Lema
>         *Sent:* Friday, November 21, 2014 5:52 PM
>         *To:* Dante Garcia
>         *Subject:* RE: eQuest - Fort Cartson
>
>         Como va?
>
>         Encontraste algo mas?
>
>         Buen finde.
>
>         *SUMAC*
>
>         *Gonzalo Lema | Mechanical Engineer | LEED GA*
>
>         Tel: +1.773.857.7906 Ext 7009 (Chicago, USA)
>
>         Tel: +1.305.814.8805 (Miami, USA)
>
>         Tel: +511.253.5355 (Lima, Perú)
>
>         Tel: +593.4.600.0613 (Guayaquil, Ecuador)
>         Tel: + 571.3151985 (Bogotá, Colombia)
>
>         glema at sumacinc.com <mailto:glema at sumacinc.com>
>
>         www.sumacinc.com <http://www.sumacinc.com/>
>
>         *From:* Dante Garcia
>         *Sent:* Thursday, November 20, 2014 5:21 PM
>         *To:* Gonzalo Lema
>         *Subject:* eQuest - Fort Cartson
>
>         Gonzalo, te envío el eQuest que revisé, todavía no encuentro
>         el error, solo edité un poco el primer piso ya que dos zonas
>         se sobreponían, mañana seguré revisando y ver si encuentro
>         algo, una consulta, viste este reporte, así son los cfm que
>         deben tener cada zona o es bien alto?
>
>         Saludos,
>
>         Dante
>
>         <image004.jpg>
>
>         *SUMAC*
>
>         *Dante Garcia, LEED AP BD+C | Analista LEED Energía*
>
>         Tel: +511.253.5355 Anexo 16 (Lima, Perú)
>
>         Cel: +51.989.685.769 (Lima, Perú)
>
>         Tel: +593.4.600.0613 (Guayaquil, Ecuador)
>         Tel: + 571.3151985 (Bogotá, Colombia)
>
>         Tel: +1.773.857.7906 (Chicago, USA)
>
>         dgarcia at sumacinc.com <mailto:dgarcia at sumacinc.com>
>
>         www.sumacinc.com <http://www.sumacinc.com>
>
>         ZGF Email Disclaimer
>         <https://www.zgf.com/ZGF_Email_Disclaimer.html>
>
>
>
>
>
>         _______________________________________________
>
>         Equest-users mailing list
>
>         http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
>
>         To unsubscribe from this mailing list send  a blank message toEQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG  <mailto:EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20141201/56752a3f/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 25867 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20141201/56752a3f/attachment.png>


More information about the Equest-users mailing list