[Equest-users] PSZ Dehumidification reheat?

Bishop, Bill via Equest-users equest-users at lists.onebuilding.org
Mon Apr 25 14:23:02 PDT 2016


Hi Mike,
With a PSZ, your ZONE-HEAT-SOURCE will only get applied at your subzones (non-control zone(s)). The heat pump will operate to satisfy both the control zone thermostat and the humidity requirement based on the RH of the return air. For a DOAS heat pump PSZ serving multiple zones, the supply air temperature at the control zone will vary considerably on a sub-hourly basis as the heat pump cycles between cooling and heating mode to prevent overcooling the zone, but reheat can be used to keep the SAT to the subzones relatively constant. Give this input a try to get you close to your description:
"DOAS me no questions" = SYSTEM
   TYPE             = PSZ
   HEAT-SOURCE      = HEAT-PUMP
   ZONE-HEAT-SOURCE = ELECTRIC
   MAX-SUPPLY-T     = 73
   MIN-SUPPLY-T     = 55
   MAX-HUMIDITY     = 60
   REHEAT-DELTA-T   = 18

Regards,
~Bill

William Bishop, PE, BEMP, BEAP, CEM, LEED AP | Pathfinder Engineers & Architects LLP
Senior Energy Engineer

[cid:image007.jpg at 01D19F17.1E1F5890]  [cid:image008.jpg at 01D19F17.1E1F5890]



134 South Fitzhugh Street                 Rochester, NY 14608

T: (585) 698-1956                        F: (585) 325-6005

bbishop at pathfinder-ea.com<mailto:wbishop at pathfinder-ea.com>             www.pathfinder-ea.com<http://www.pathfinder-ea.com/>

[http://png-5.findicons.com/files/icons/977/rrze/720/globe.png]Carbon Fee and Dividend - simple, effective, and market-based.


From: Equest-users [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Michael Campbell via Equest-users
Sent: Monday, April 25, 2016 9:17 AM
To: equest-users at lists.onebuilding.org
Subject: [Equest-users] PSZ Dehumidification reheat?

Hello,
Hoping someone can help me out here.  I am modeling a PSZ heat pump with ERV as a DOAS.  It is supposed to dehumidify to keep RH below 60%.  It appears to be doing this currently based on the hourly reports.  However, I need to also model an electric resistance coil that will reheat the dehumidified air back up to 73F.  Does anyone know how I can accomplish this with PSZ?  I've tried making "ZONE-HEAT-SOURCE" electric resistance, but this does not seem to have any effect at all.  I also thought about applying preheat to the zones served by the DOAS but  it states in the item description that preheat is appled to the mixed air flow, not just outside air so that won't work for me.  Any recommendations?
Thank you,
Mike C
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160425/4ee6b855/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image007.jpg
Type: image/jpeg
Size: 1517 bytes
Desc: image007.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160425/4ee6b855/attachment-0004.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image008.jpg
Type: image/jpeg
Size: 1647 bytes
Desc: image008.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160425/4ee6b855/attachment-0005.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image009.png
Type: image/png
Size: 3859 bytes
Desc: image009.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160425/4ee6b855/attachment-0002.png>


More information about the Equest-users mailing list