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

[EnergyPlus_Support] Re: Zone FanCoils and an AHU

Hello, these past days I have been working on E+ and have encountered yet another issue.


I have uploaded the file in the "Problem Submittals" folder, here is the link: http://f1.grp.yahoofs.com/v1/gMnCTbZTHApu6ysKaKqdLLPj1K4UfePyZK7sNqvhmWoXLl1g8syBJW4bCgVCC63pxK2NlmV_5zl6yX2phK84FCV5m5b9Q1SOD9zK/_Problem_Submittals/Zoneamento_Teste_03_UTA.zip


I have put one AHU to treat the air in two zones...these will be of "minor cirgury" so they have to be a separate system. Then for the remaining areas I have put a FanCoil in each zone, except the corridors, step compartment and storage areas, with zero outside air intake from the FanCoil, the outside air is being sent to each zone buy another AHU.

In EqupimentList, I gave prioprity to the AHU.
The AHU is putting the fresh outside air in the zones at 20ºC in winter and 25ºC in summer (design days). Then the FanCoils treat the zone mean air temperature so that it reaches 20ºC in winter and 25ºC in summer. All of this is working, but the Coil capacity of the AHU is huge!

With all the FanCoils, they together deliver 187 kW sensible cooling and 125 kW heating. But the AHU heating and cooling coil values are high! 117 kW for sensible cooling and 69 kW for heating. In contrast with the design cooling and heating loads that I got using the IdealLoadsAirSystem, the coils capacity is huge. I got for IdealLoadsAirSystem 163 kW sensible cooling load and 170 kW heating load.

Are these values correct for the AHU??? I don't think so, and can't figure out how to lower the values...I tried manually lowering the heating coil "Rated Capacity" but values lower than 65 KW won't give me values of 20ºC fresh outside air in winter design day.

I don't understand why did the IdealLoadsAirSystem give me heating and cooling loads of the various zones, but then when I Put an AHU to treat these zones the CoolingCoil and HeatingCoil are much bigger than the loads (over twice the amount) --> IdealLoadsAirSystem gave me lower than 200 kW, using an AHU the coils get over 400 kW?!


Thank-you for the help



------------------------------------

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.
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/join
    (Yahoo! ID required)

<*> To change settings via email:
    EnergyPlus_Support-digest@xxxxxxxxxxxxxxx 
    EnergyPlus_Support-fullfeatured@xxxxxxxxxxxxxxx

<*> To unsubscribe from this group, send an email to:
    EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/