Hey Ed, is 400 CFM always the correct airflow?
In this edition of “Hey Ed,” Ed discusses the correct airflow.
Hey Ed, is 400 CFM always the correct airflow? This is a volume that I hear quite frequently. And if you were to run every air conditioning system that you touched for the rest of your life, it’s going to make air conditioning. Is it going to make the proper amount of air conditioning for the dwelling? Well, I don’t know the answer to that. Because sometimes we need lower than 400 CFM per ton. Example would be a house that needs more moisture removal. We could have a house that has very little moisture in it, and it will benefit from something greater than 400 CFM per ton. At the end of the day, follow the guidance and manuals, and know what your proper airflow is supposed to be. And that’s the way I see it.
- Hey Ed, is 400 CFM always the correct airflow? - October 15, 2025
- Hey Ed, What’s the difference between 100 CFM coming out of a metal duct or a flex duct? - October 8, 2025
- Hey Ed, Does the new Manual S® still have a path to size based on AC requirement? - October 1, 2025
Ed Janowiak is the Manager of HVAC Design Education at ACCA.
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Posted In: Hey Ed, Technical Tips