ventilation in ideal loads

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I have seen in various other questions (e.g. here and here) and even in energy plus report itself that ventilation loads are not included while performing simulation with ideal loads system. However, when I change the DesignSpecificationOutdoorAir for a single zone test I did with ideal loads, cooling and heating loads also change by roughly what I would calculate manually for the sensible part of ventilation. Thusly I assume that the sensible part of ventilation is also reported in HVAC sizing summary. I would appreciate if someone could confirm or refute this finding! thank you!

answered 7 years ago

Avi
4320 ●2 ●11

I can confirm that whenever you select idle loads in OS and populated the model's design specification OA the OA object will be registered in the HVACTemplate:Zone:IdealLoadsAirSystem , and later will be expanded into ZoneHVAC:IdealLoadsAirSystem. The design specification OA will be referred by the Sizing:Zone as well. So it make sense that the sensible part of the OA will show up in the Idle Loads. Actually I was also able to include latent loads (including OA) into idle loads but that required using this E+ measure. For that you will have to select Humidistat and to add dehumidification setpoint in the Thermal Zones tab.

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The html report was specific that no ventilation loads are included and it had me troubled! Thank you for your time to answer my question as well as for the measure!

Petros Dalavouras ( 7 years ago )

Well I double checked myself and the above is true only when I use the E+ measure. So OA object is not automatically added to HVACTemplate:Zone:IdealLoadsAirSystem. On the other hand the OA object is registered into the Sizing:Zone which explains your observation.