FAQs

Rated Positive Pressure: 10” w.g. per UL 181 Recommended Operating Pressures: 6” w.g. pos., 4”-12” dia., 4”w.g. pos., 14”-20” dia.; ¾” neg., all dia. Velocity:

ATCO’s UL Listed pressure ratings are determined by testing ducts in straight lengths, at ambient temperatures. Testing is done in a static condition (no airflow).