ASHRAE November 23, 2021 draft text duct systems Click here to purchase Product Details Published: 2020 Units of Measure: I-P File Size: 1 file , 140 KB Product Code(s): D-90556 You May Also Like ASHRAE Guideline 36: Best in Class HVAC Control Sequences ASHRAE Principles of Heating, Ventilating, and Air Conditioning, 9th Ed.