HVAC Flow Rate Calculator
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This HVAC Flow Rate Calculator is free to use. Make snap decisions at a glance!
What is an HVAC flow rate calculator?
An HVAC flow rate calculator is a tool that offers a fast overview of an HVAC unit’s production. It determines the amount of fluid that passes through a given cross-sectional area of a duct or pipe over a specific period of time in cubic feet per second. Our calculator is so easy to use, anyone on your team can easily calculate the flow rate.
Who uses an HVAC flow rate calculator?
Both HVAC technicians and property owners use HVAC flow rate calculators. They can make informed decisions based on the results to ensure the proper installation of the HVAC unit. This means the desired space will reach the right temperature without wasting any extra time.
How accurate are the results?
The accuracy of the results depends on the precision of the information entered and the assumptions made by the calculator. Other external factors may also affect or falsify the recommendations. For the most accurate results, we’d advise consulting a licensed technician/engineer.
How do you calculate the HVAC flow rate?
– One way to calculate the flow rate is by using the diameter of the duct/pipe and the velocity of the fluid. Another is to measure it using the volume of the duct/pipe and the time it takes the fluid to travel.
– Add the relevant details in order to get the estimated flow rate. The details will include: diameter, velocity, volume, and time.
– With the calculation, you should have an estimate of the HVAC flow rate for your needs at the bottom of the calculator page.
HVAC Flow Rate Calculation Formula Examples:
1. Diameter and Velocity
3.14 × [{(Diameter in inch/12) × (Diameter in inch/12)} / 4] × Velocity = Flow Rate
The above formula estimates the base HVAC flow rate using the diameter and the velocity.
For example, let’s say there’s a duct with an 8-inch diameter and the velocity of the fluid is 20 feet/second. The formula to calculate the estimated HVAC flow rate would be: 3.14 × [{(8/12) × (8/12)} / 4] × 20 = 6.978 cubic feet/second.
OR
2. Volume and Time
You can also estimate the base HVAC flow rate using the volume and the time.
Volume/Time = Flow Rate
For example, let’s say there’s a duct with a volume of 10 cubic feet and the time required for the fluid to travel is 2 seconds. The formula to calculate the estimated HVAC flow rate would be: 10/2 = 5 cubic feet/second