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RefBldgOutPatientNew2004_Chicago

asked 2018-01-31 12:09:00 -0500

GONGHJ gravatar image

updated 2018-01-31 15:02:39 -0500

I have spikes when running E+ example file 'RefBldgOutPatientNew2004_Chicago.idf'. I think the problem is caused by HVAC sizing. The problem is within outputvariable: 'Whole Building:Facility Total HVAC Electric Demand Power W '

The run data is set to 7/01, timestep is 20, and weather data is 'USA_IL_Chicago-OHare.Intl.AP.725300_TMY3.epw'.

Is there any way of avoiding such spikes?

I am sorry I don't have enough points to post the figures.

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answered 2018-01-31 13:04:47 -0500

updated 2018-02-01 07:04:49 -0500

If you are autosizing, set the averaging window to 1 hour or more (3 time steps). If not autosizing, then the system may be oversized.

Sizing:Parameters,
  1,                                      !- Heating Sizing Factor
  1,                                      !- Cooling Sizing Factor
  3;                                      !- Timesteps in Averaging Window
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thank you very much. It works well when I just run the default design day. But if I use weather data, then there are spikes.

Do you know what would be the potential causation? thanks.

GONGHJ gravatar image GONGHJ  ( 2018-05-03 10:09:35 -0500 )edit

Compare the size of the HVAC (see eio or html files for autosizing results) when changing the averaging window from 1 to 3 to 5 and see how this impacts the electricity spikes.

rraustad gravatar image rraustad  ( 2018-05-03 10:19:59 -0500 )edit

Thank you very much. By checking the HVAC sizing summary, I found there is only autosized HVAC for the design days. Those spikes appear in the days using weather data. Could you please give me more advice?

thanks.

GONGHJ gravatar image GONGHJ  ( 2018-05-04 14:08:53 -0500 )edit

Plot zone temp and set point and HVAC sensible (or total) capacity then zoom in on one day to see whats happening.

rraustad gravatar image rraustad  ( 2018-05-06 20:25:48 -0500 )edit

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Asked: 2018-01-31 12:09:00 -0500

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Last updated: Feb 01 '18