How to calibrate a vav unit

If you are using a pressure independent controller for a variable air volume unit, then you go for static calibration method since it is easy. I'e, u take a base points (2 values) one is the flow at maximum manual open position of the vav and second the differential pressure at same position. By entering these values in to the program and nominal volume (i.e, (Vnom) maximum manufacturer's design flow). Answer by ASHFAQ

Up to now you have got a base point on which you can depend and calibrate your vav. By entering your room design flow values in to max, min flows of your software you can get an approx flow, then apply some factor into your base data and set it for your design.