1. What is the Blower Door Fan Flow Equation?

The Blower Door Fan Flow equation calculates the airflow through a blower door fan based on pressure and fan curve factor. It is essential for assessing building airtightness and ventilation performance in energy efficiency testing.

2. How Does the Calculator Work?

The calculator uses the Blower Door Fan Flow equation:

Where:

• \( Pressure \) — Pressure in Pascals (Pa)
• \( Fan\ Curve\ Factor \) — Fan curve factor in CFM per Pascal (CFM/Pa)

Explanation: The equation directly multiplies pressure by the fan curve factor to determine the airflow rate in cubic feet per minute (CFM).

3. Importance of Fan Flow Calculation

Details: Accurate fan flow calculation is crucial for evaluating building envelope integrity, determining ventilation requirements, and ensuring compliance with energy efficiency standards.

4. Using the Calculator

Tips: Enter pressure in Pascals (Pa) and fan curve factor in CFM per Pascal (CFM/Pa). All values must be valid (greater than 0).

5. Frequently Asked Questions (FAQ)

Q1: What is a blower door test?
A: A blower door test is a diagnostic tool used to measure the airtightness of buildings and identify air leakage locations.

Q2: How is fan curve factor determined?
A: Fan curve factor is typically provided by the blower door manufacturer and represents the airflow per unit pressure for the specific fan model.

Q3: What are typical pressure values in blower door testing?
A: Testing is usually conducted at 50 Pa pressure difference, but multiple pressure points may be used to characterize building performance.

Q4: Why is CFM used for airflow measurement?
A: CFM (cubic feet per minute) is a standard unit for airflow measurement in ventilation and building performance testing, particularly in the United States.

Q5: Can this calculator be used for different fan types?
A: This calculation is specific to blower door fans with known fan curve factors. Other fan types may require different calculation methods.