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DesignDay in EP+ is necessary if without HVAC

asked 2021-07-12 10:40:45 -0500

wei_zhang's avatar

updated 2021-07-12 11:00:20 -0500

Hello everyone

I have a question about the design day in EP+/OpenStudio. I understand for now that the DesignDay is for the general HVAC sizing. If I firstly model a whole building with all passive building systems (without any motorized or mechanical elements), could I run this building simulation without DDY file? Is there any negative impact on this workflow? My intention is to separate the passive building/systems simulation from active features in buildings.

Thanks in advance


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answered 2021-07-12 18:13:21 -0500

That is correct. You do not need Design Days to be defined in your model if you have either:

  1. No HVAC system to be autosized in your model,
  2. A hardsized (i.e., user-entered sizing values rather than autosized) HVAC system in your model, or
  3. An autosized HVAC system using an alternative sizing method (e.g., using SizingPeriod:WeatherFileDays).
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Thanks Scott for your reply

wei_zhang's avatar wei_zhang  ( 2021-07-12 20:26:38 -0500 )edit

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Asked: 2021-07-12 10:40:45 -0500

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Last updated: Feb 19 '22