[Equest-users] eQuest - FCU with DOAS

[Kevin Kyte]

I would agree with Jonathan's second approach, include the fan power from the DOAS into the energy recovery of the FCUs.  If the DOAS has heating I suppose it could be accounted for under preheating, though I have not tried that one yet.  I have been told that using dummy zones is not necessary good practice with equest though it has been awhile since then.  Good luck.

Kevin

________________________________
From: Grando, John [mailto:JGrando at cosentini.com]
Sent: Thursday, March 04, 2010 2:15 PM
To: Jonathan Curtin; James Hansen; Marcus Eliason; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] eQuest - FCU with DOAS

Thanks, what do you think about using preheating the exhaust (i'm doing OA cooling only) to a temp that i'm fairly certain is the zone max exhaust temp (75F) and then just subtracting out the energy used to preheat the exhaust temp after the model runs?  Any comments?

John Grando LEED AP




________________________________
From: Jonathan Curtin [mailto:jcurtin at WylieAssociates.com]
Sent: Monday, March 01, 2010 4:57 PM
To: Grando, John; James Hansen; Marcus Eliason; equest-users at lists.onebuilding.org
Subject: RE: [Equest-users] eQuest - FCU with DOAS

All,

I believe it is the RA temperature of the Dummy Zone that is passed to the units with OA-From specified, so you are right John that the RA would be too cold to return to an ERV, assuming your dummy space is something around 55F.

I have spent many a late night trying to work around this problem and can recommend the following approaches:
1. Model any Energy Recovery as an exceptional calculation (in a separate model) for LEED
2. Incorporate the Energy Recovery into the FCUs or AHUs (although you have to be really careful to properly account for your fan energy and flow rates).

Regards,

  Jonathan M. Curtin, EIT, LEED® AP
  Mechanical Engineer
 [cid:image001.jpg at 01CABBAD.B2E6B1C0]

-----Original Message-----
From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Grando, John
Sent: Monday, March 01, 2010 03:08 PM
To: James Hansen; Marcus Eliason; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] eQuest - FCU with DOAS


One further question that has been bothering me.  How would you set up ERV with the DOAS?  I've seen some posts from the archives but none are too clear.  The return air temperature of the DOAS appears to be too low to use an ERV on. Any suggestions?


John Grando LEED AP


-----Original Message-----
From: James Hansen [mailto:JHANSEN at ghtltd.com]
Sent: Monday, March 01, 2010 11:16 AM
To: Marcus Eliason; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] eQuest - FCU with DOAS

I haven't had a chance to look at your .inp file, but when you are creating a DOAS system, make sure that you at least do the following:

1) Make sure the fan schedule is forced off at night and setback times.
2) Make sure the throttling range for the dummy zone thermostat is at least 4 degrees (I usually use 6).
3) Make sure that the heating/cooling schedules that the dummy zone follows are set to something like 120 degrees cooling and 20 degrees heating after hours, just to make sure that a call for heating/cooling doesn't show up in your report, and mess up the unmet load hours.


Just looked at your file:  you need to specify some sort of minimum OA control or minimum air schedule for the FCUs (I think).  Right now nothing shows up.

Also, why is the DOAS system serving so many "dummy" zones?  I *think* your DOAS system is EL1 Sys1 (SZRH), yet it is serving 20+ zones.  I'm confused...

GHT Limited
James Hansen, PE, LEED AP
Senior Associate
1010 N. Glebe Rd, Suite 200
Arlington, VA  22201-4749
703-338-5754 (Cell)
703-243-1200 (Office)
703-276-1376 (Fax)
www.ghtltd.com



-----Original Message-----
From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Marcus Eliason
Sent: Monday, March 01, 2010 11:04 AM
To: equest-users at lists.onebuilding.org
Subject: [Equest-users] eQuest - FCU with DOAS


Hello,

I am trying to model a building with FCUs and a DOAS to deliver outdoor air to the individual zones.  I have put in the dummy zones for the DOAS system, modeled as a single air handler with chilled and hot water coils. I have changed the walls of the dummy zone to air walls, specified the DOAS to get OA flow as sum of all zones and for the FCUs to get OA from the DOAS.  When I run the model, I get a lot of unmet hours corresponding to the dummy zones and the DOAS system.  I have tried but cannot seem to turn off the return air path for the DOAS (since it is 100% OA) and have specified the minimum OA fraction for the DOAS as 1.  I am not sure if the unmet hours means that my DOAS is not adequately cooling the OA load or if it something else.
Also, my "pump & aux" energy in the model seems very high for a building that only has 3 pumps.  Can someone familiar with modeling DOAS shed any light on what might be causing some of these problems.  I have attached the .inp and .pd2 files for reference.

Thanks,

Marcus Eliason



The information contained in this communication is confidential, may be privileged, and is intended only for the use of the addressee.  It is the property of GHT Limited.  Unauthorized use, disclosure or copying of this communication or any part thereof is strictly prohibited and may be unlawful.  If you have received this communication in error, please notify me immediately by return e-mail or by e-mail to ght at ghtltd.com, and destroy this communication and all copies thereof, including all attachments.  Thank you.





NOTICE OF CONFIDENTIALITY

This E-mail message and its attachments (if any) are intended solely for the use of the addressees hereof.  In addition, this message and the attachments (if any) may contain information that is confidential, privileged and exempt from disclosure under applicable law.  If you are not the intended recipient of this message, you are prohibited from reading, disclosing, reproducing, distributing, disseminating or otherwise using this transmission.  Delivery of this message to any person other than the intended recipient is not intended to waive any right or privilege.  If you have received this message in error, please promptly notify the sender by reply E-mail and immediately delete this message from your system.


_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuildingorg<http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org>
To unsubscribe from this mailing list send  a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG

________________________________
Legal Disclaimer: The information contained in this communication is confidential and is covered by the Electronic Communications Privacy Act, 18 U.S.C. §§ 2510-2521; it may be privileged and is intended for the exclusive use of the above named addressee(s). If you are not the intended recipient(s), you are expressly prohibited from copying, distributing, disseminating, or in any other way using any of the information contained within this communication. If you have received this communication in error, please contact the sender by telephone at (713) 781-2526 or by response via email and permanently delete the original email (including attachments) and any copies.

Please consider the environment before printing this email.

NOTICE OF CONFIDENTIALITY This E-mail message and its attachments (if any) are intended solely for the use of the addressees hereof. In addition, this message and the attachments (if any) may contain information that is confidential, privileged and exempt from disclosure under applicable law. If you are not the intended recipient of this message, you are prohibited from reading, disclosing, reproducing, distributing, disseminating or otherwise using this transmission. Delivery of this message to any person other than the intended recipient is not intended to waive any right or privilege. If you have received this message in error, please promptly notify the sender by reply E-mail and immediately delete this message from your system.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20100304/3688d7ab/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 5651 bytes
Desc: image001.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20100304/3688d7ab/attachment.jpg>