CFM from BTU / Tons Calculator
Estimate required airflow in CFM from cooling tons or BTU/h using a target airflow-per-ton value. Set airflow targets before diagnosing performance.
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Frequently asked questions
How do you estimate CFM from tons?
Multiply system tons by the target airflow per ton. A common rule of thumb is 400 CFM per ton, though actual systems may vary.
How do you convert BTU/h to tons?
Divide BTU/h by 12,000 to convert to cooling tons.
Is 400 CFM per ton always correct?
No. 400 CFM per ton is a common starting point, but actual airflow targets can vary depending on equipment, humidity control goals, and manufacturer requirements.
Can this replace manufacturer airflow tables?
No. This calculator is a quick estimator. Final airflow should be confirmed using equipment data, blower tables, duct design, and measured performance.
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