Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
Hi,
I can give you a partial answer, when using AHUs, ie your VAV system in EnergyPlus/OpenStudio, the main controller for OA is: OS:ControllerOutdoorAir, in here you can control the amount and schedule for your outdoor air. As far as I know this overrides everything. So in the minimum OA entry field, put your minimum outdoor air value. Then, in the minimum limit type field put "fixed minimum", finally in the minimum outdoor air schedule field put in a fractional schedule to describe how you want your outdoor air to come into your unit. Ie, if you have 24hour fresh air it would look like this "outdoor air schedule, Fraction, through: 12/31. For: AllDays, Until: 24:00, 1". That will control your OA through your AHUs.
I believe the next level of hierarchy for OA control is in the zone equipment, the numbers you put in here will control how much OA goes into your zones. The design specification outdoor air does not override any of these values. I think this is more for sizing your system than the running of your system.
