Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
"Is this related to the "Control for outdoor air" option I see in the GUI when I click on the air terminal unit?"
Yes.
"How is this possible? And how can I force the system to deliver at least the min OA?"
EnergyPlus is perfectly fine with the terminals turning down below what is required to meet your OA specification. Out the box an OpenStudio generated model will be sized to meet your design OA specification when the terminals are running at design. As they turn down you may under ventilate.
To keep this from happening you can use the OpenStudio property on the VAV terminal Control For Outdoor Air. This will make sure that the terminal requests the minimum amount of air to meet the attached zone's OA specification, even if the zone load doesn't call for that much flow.
| | 2 | No.2 Revision |
"Is this related to the "Control for outdoor air" option I see in the GUI when I click on the air terminal unit?"
Yes.
"How is this possible? And how can I force the system to deliver at least the min OA?"
EnergyPlus is perfectly fine with the VAV terminals turning down below what is required to meet your OA specification. Out the box an OpenStudio generated model will be sized to meet your design OA specification when the terminals are running at design. As they turn down you may under ventilate.
To keep this from happening you can use the OpenStudio property on the VAV terminal Control For Outdoor Air. This will make sure that the terminal requests the minimum amount of air to meet the attached zone's OA specification, even if the zone load doesn't call for that much flow.
