1. What is an Air Filter Flow Rate Calculator?

Definition: This calculator estimates the volumetric flow rate of air through a filter in gallons per minute (GPM equivalent).

Purpose: It helps HVAC professionals and engineers determine the air flow capacity of filtration systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (GPM equivalent)
• \( V \) — Air velocity (feet per second)
• \( A \) — Filter area (square feet)
• 448.83 — Conversion factor (ft³/s to GPM)

Explanation: The air velocity multiplied by filter area gives volumetric flow in ft³/s, which is then converted to GPM.

3. Importance of Air Flow Rate Calculation

Details: Proper flow rate estimation ensures adequate filtration, system efficiency, and prevents overloading of HVAC components.

4. Using the Calculator

Tips: Enter the air velocity in ft/s and filter area in ft². Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why convert to GPM when measuring air flow?
A: GPM equivalent allows comparison with liquid flow rates in integrated systems.

Q2: What's a typical air velocity through filters?
A: Residential systems typically use 300-500 ft/min (5-8.33 ft/s), while commercial may be higher.

Q3: How do I measure filter area?
A: Multiply length by width of the filter face area in square feet.

Q4: Does this account for filter resistance?
A: No, this calculates theoretical flow. Actual flow may be lower due to filter media resistance.

Q5: Can I use this for other gases?
A: The conversion factor is air-specific. For other gases, adjust the density factor accordingly.