Minimum Outdoor Air for Rooftops

[BACN_mechanical]

Hello everyone,

Do you know if there is a minimum percentage of outdoor air for rooftops? For example, if after calculating the supply air flow and outdoor air, the percentage of outdoor air is 5%. Is it possible for the roof to provide that percentage of outdoor air or less? Is there a problem with the damper control?

Regards

 

[HVAC-Novice]

it depends on the space served. If the equipment is on the roof, or an AHU in a mechanical room, is not relevant.

 

[nuuvox000]

You can set the damper to open/close to provide your 5% or greater outdoor air CFM. Depending on the building, application, energy code, etc, it may need to close when the building is unoccupied. A balancing contractor can set the damper to the correct position.