HVAC CFM Calculator
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This HVAC CFM Calculator determines the required airflow rate based on cubic feet per minute (CFM) and air changes per hour (ACH).
What is an HVAC CFM calculator?
An HVAC CFM calculator is a tool that allows you to quickly determine the required airflow rate for any room based on cubic feet per minute (CFM) and air changes per hour (ACH). Our HVAC CFM calculator is free and easy to use—anyone can easily calculate the CFM for a given area.
Who uses an HVAC CFM calculator?
An HVAC CFM calculator is used by HVAC techs and property owners. They can make informed decisions based on the results and ensure the proper installation of an HVAC unit. This allows the desired space to reach the right temperature without wasting any extra time.
How accurate are the results?
The results depend on the accuracy of the input parameters and the assumptions made by the calculator. Other external factors may also affect or falsify the recommendations. To get the most accurate results, consult a licensed tech or engineer.
How do you calculate the HVAC CFM?
Step 1: To calculate the CFM, first determine the volume of the room in cubic feet. Multiply that by the recommended ACH, and divide everything by 60 minutes per hour.
Step 2: Add the relevant details to get the estimated CFM. The details will include metrics like: room length, room width, ceiling height, and air changes per hour.
Step 3: Once you have the relevant information, you should be able to get an estimate of the HVAC CFM for your needs at the bottom of the calculator page. The floor area of the room (length × width) and volume of the room (floor area × height) are determined automatically in our calculator.
HVAC CFM Calculation Formula and Example:
CFM (Airflow) = [(Floor Area × Ceiling Height) × ACH] / 60
The above formula is utilized to estimate the base HVAC CFM using the room length, room width, ceiling height, and air changes per hour.
For example, to calculate the estimated HVAC CFM of a room that has a length of 10 feet, width of 6 feet, ceiling height of 10 feet, and ACH of 6, the formula would be:
[(60 × 10) × 6] / 60 = 60 CFM