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HVAC Heating Load Calculator

Heating Load Formula:

\[ BTU/h = Area \times 30 \]

sq ft

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1. What is HVAC Heating Load?

The HVAC heating load is the amount of heat energy required to maintain comfortable temperatures in a space. It's measured in British Thermal Units per hour (BTU/h) and helps determine the appropriate size for heating systems.

2. How Does the Calculator Work?

The calculator uses the basic heating load formula:

\[ BTU/h = Area \times 30 \]

Where:

Explanation: This simplified formula estimates heating needs based on square footage, using 30 BTU/h per square foot as a general rule for moderate climates.

3. Importance of Heating Load Calculation

Details: Proper heating load calculation ensures your HVAC system is correctly sized - neither too small (inadequate heating) nor too large (short cycling, inefficiency).

4. Using the Calculator

Tips: Enter the area in square feet. For more precise calculations, consider factors like insulation, window quality, and local climate.

5. Frequently Asked Questions (FAQ)

Q1: Is 30 BTU/h per sq ft accurate for all situations?
A: This is a general estimate. Colder climates may need 40-60 BTU/h per sq ft, while warmer areas may need only 20-30.

Q2: What other factors affect heating load?
A: Insulation quality, window types, ceiling height, outdoor temperatures, and air infiltration all impact heating needs.

Q3: Should I use this for whole-house calculations?
A: For whole-house systems, professional Manual J calculations are recommended as they consider all variables.

Q4: How does this relate to furnace sizing?
A: The total BTU/h requirement helps determine the appropriate furnace output capacity.

Q5: What about cooling load?
A: Cooling load calculations are different and typically require more factors like solar gain and internal heat sources.

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