To calculate the CFM (Cubic Feet per Minute) of an Air Handling Unit (AHU), you need to know the airflow rate and the area of the duct or opening through which the air is flowing. Here's a general formula you can use:
CFM = Airflow Rate (in cubic feet per second) × 60
To determine the airflow rate, you may need to consult the manufacturer's specifications or perform airflow measurements using instruments such as an anemometer or a flow hood. Once you have the airflow rate in cubic feet per second (ft³/s), you can multiply it by 60 to convert it to CFM.
It's important to note that AHUs often have multiple fans or sections with different airflow rates. In such cases, you will need to calculate the CFM for each section separately and then sum them up to get the total CFM for the AHU.
Remember that this is a general approach, and for accurate calculations specific to your AHU, it's best to consult the manufacturer's documentation or work with an HVAC professional.