Cfm To Btu Hr Calculator

CFM to BTU/hr Formula:

\[ BTU/hr = CFM \times 1.08 \times \Delta T \]

BTU/hr (British Thermal Units Per Hour):

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1. What is the CFM to BTU/hr Conversion?

The CFM to BTU/hr conversion calculates the heating or cooling capacity of air flow in British thermal units per hour based on cubic feet per minute of air flow and temperature difference. This is essential for HVAC system design and analysis.

2. How Does the Calculator Work?

The calculator uses the standard HVAC formula:

\[ BTU/hr = CFM \times 1.08 \times \Delta T \]

Where:

\( CFM \) — Cubic feet per minute (air flow rate)
\( \Delta T \) — Temperature difference in degrees Fahrenheit
\( 1.08 \) — Conversion constant (accounts for air density and specific heat)

Explanation: The constant 1.08 is derived from the specific heat of air (0.24 BTU/lb-°F) and the density of standard air (0.075 lb/ft³), multiplied by 60 minutes per hour.

3. Importance of BTU/hr Calculation

Details: Accurate BTU/hr calculation is crucial for proper HVAC system sizing, energy efficiency analysis, and ensuring adequate heating or cooling capacity for residential and commercial spaces.

4. Using the Calculator

Tips: Enter CFM value (must be greater than 0) and temperature difference in °F. The calculator will provide the corresponding BTU/hr value for heating or cooling applications.

5. Frequently Asked Questions (FAQ)

Q1: What does the 1.08 constant represent?
A: The 1.08 constant combines air density (0.075 lb/ft³), specific heat of air (0.24 BTU/lb-°F), and minutes to hours conversion (60 min/hr).

Q2: When is this calculation used?
A: This calculation is commonly used in HVAC design for sizing heaters, air conditioners, and determining heat transfer in ventilation systems.

Q3: What are typical CFM values?
A: Residential systems typically range from 400-2000 CFM, while commercial systems can range from 2000-20,000+ CFM depending on building size.

Q4: Does this work for both heating and cooling?
A: Yes, the formula works for both heating and cooling applications. For cooling, ΔT represents the temperature drop; for heating, it represents temperature rise.

Q5: What are the limitations of this formula?
A: This formula assumes standard air conditions. It may need adjustment for high altitude applications, extreme temperatures, or non-standard air compositions.