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Difference between design specification outdoor air and space infiltration design flow rates

asked 2022-09-28 17:47:25 -0600

Charlotte123's avatar

updated 2022-09-29 09:08:33 -0600

Hi there,

I am trying to model a residential building in OpenStudio and am on to infiltration but I am very confused what the difference is between design specification outdoor air and space infiltration design flow rates. Would someone be able to explain this to me?

For the residential building I know ACH should be 0.25 but am unsure which infiltration category this comes under, if someone is able to clarify?


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answered 2022-10-01 07:21:30 -0600

updated 2022-10-01 07:23:33 -0600

In E+, DesignSpecification:OutdoorAir defines intentional ventilation outdoor air (calculation methodology and flow rates, optionally defined as ACH). This is usually required for zone load calculations, sizing calculations, HVAC controllers, etc.

In E+, ZoneInfiltration:DesignFlowRate describes unintentional infiltration rates (optionally as ACH). Similarly required for zone load calculations and sizing calculations.

In OpenStudio, both objects are associated to Spaces.

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Great thanks for that

Charlotte123's avatar Charlotte123  ( 2022-10-07 16:41:34 -0600 )edit

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Asked: 2022-09-28 17:20:08 -0600

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Last updated: Oct 01 '22