[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [EnergyPlus_Support] dualsetpoint deadband





There is no deadband on Tstat setpoints in E+. If you want the fan to cycle, set the fan operating mode schedule to 0. This only works for systems that can utilize cycling fan mode. For example, UnitarySystems, Furnaces, and some ZoneHVAC equipment.

  AirLoopHVAC:Unitary:Furnace:HeatCool,
    CyclingFanSchedule,      !- Supply Air Fan Operating Mode Schedule Name


On 6/3/2011 2:06 PM, moana wrote:
 


Sorry All,
Disregard my previous message, when i exported the geometry from design builder it assigned a schedule to the reporting of the mean air temperature which shifted the curve when i was viewing it in the Result Viewer.
I had another question though. When using the dualsetpoint thermostat is there a way to enter a deadband on the heating and on the cooling setpoints? As deadband I mean for example if the heating setpoint is 20C, i would like to allow a +/- 1 degree around it so that the fans don't run constantly but intermittently rather.

Thanks

Moana

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "moana" <moana.reynau@...> wrote:
>
> Hi All,
>
> I'm trying to model a simple VAV system with local reheat (PIU). When I set up the availability of the air terminals to - always on - The indoor temperature is maintained within the setpoints. The problem is that at night the parallel fan runs all the time. When I set up a schedule with the fans off at night there is a short swing in temperature in the evening below the setpoint (17 deg C). Then the temperature goes back to normal.
> I checked the sizing of the heating coils and flow. Entered the values back manually and tried to oversize as well (doubles the capacity) without any effect.
> I also checked the timestep and bumped it to 30. No change.
> If you check the attached file the problem occurs in the winter (there's an example around 4th Dec).
> There's an old post from 06 refering to a similar problem. http://tech.groups.yahoo.com/group/EnergyPlus_Support/message/6649
> Not sure if this is still the same.
>
>
> Thanks for your help!
>
> The idf file is in the Files/Problem_submittals folder.
>
>
> Moana
>


-- 
Richard A. Raustad
Senior Research Engineer
Florida Solar Energy Center
University of Central Florida
1679 Clearlake Road
Cocoa, FL  32922-5703
Phone:   (321) 638-1454
Fax:     (321) 638-1439 or 1010
Visit our web site at: http://www.fsec.ucf.edu

UCF - From Promise to Prominence: Celebrating 40 Years


__._,_.___


Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx

The primary EnergyPlus web site is found at:
http://www.energyplus.gov

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.




Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe

__,_._,___