I am modeling an existing building with several roof top VAV systems. I have system model numbers so I did not autosize any of the Coil:Cooling:DX:TwoSpeed system. The SHR inputs for the model and error messages running the model make
no sense to me:
Manufacturer data says SHR at low speed is much lower than at high speed (makes perfect sense to me), but E+ complains if the high speed and low speed SHR differ too much.
Using manufacturer data to calculate SHR inputs results in psychrometric calculation errors about RH exceeding 100%. While the error message would suggest that more latent cooling is needed (lower SHR) the actual fix is to increase the
SHR (less latent cooling).
So my model runs now runs without complaints with high speed SHR = low speed SHR = 0.77, not close to the manufacturer data. I would appreciate it if anyone could explain this E+ logic to me this.
Ned Lyon, P.E. (MA, WV)
Staff Consultant
SIMPSON GUMPERTZ & HEGER
|
Engineering of Structures and Building Enclosures
41 Seyon Street, Building 1, Suite 500
Waltham, MA 02453
781.907.9000 main
781.907.9350 direct
617.285.2162 mobile
781.907.9009 fax
www.sgh.com
Send Files
__._,_.___
Posted by: "Edward G. Lyon" <EGLyon@xxxxxxx>
EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx
The EnergyPlus web site is found at:
http://www.energyplus.net/
The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/
Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files.
EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
__,_._,___