HVAC Procedure and Performance Guide

TASK: Determine Location and Size of Ventilation Air Intake

Training for this procedure can be found in these courses:

                         123 – Air Distribution   and   205 – HVAC High Efficiency Ventilation


Ventilation air intake must be located in protected area.  Length of intake duct must be minimized.  Air intake must be equipped with balancing damper, weather cap and insect screen.


  1. Review duct installation specifications and drawings.
  2. Select location of ventilation air intake considering the following:
    • Unobstructed air-flow into intake.
    • Sheltered area if possible.
    • Area free of air-borne contaminants.
    • Area that minimizes unauthorized tampering.
    • Convenience to interior connection.
  3. Determine size of ventilation air intake.
    • Determine required ventilation air-flow.
    • Size intake using standard charts and formulas.
  4. Document information and prepare sketch of ventilation air intake including balancing damper, screen and weather hood.