1. What is HVAC Load Calculation?

HVAC load calculation determines the heating and cooling capacity needed for a space by considering heat transfer through conduction, air infiltration, ventilation requirements, and internal heat gains. Accurate calculations ensure proper system sizing and energy efficiency.

2. How Does the Calculator Work?

The calculator uses the basic load equation:

Where:

• \( Conduction \) — Heat transfer through walls, windows, roof (BTU/h)
• \( Infiltration \) — Heat loss/gain from air leaks (BTU/h)
• \( Ventilation \) — Heat from required fresh air (BTU/h)
• \( Internal\ Gains \) — Heat from occupants, lights, equipment (BTU/h)

Explanation: This simplified equation sums all major heat transfer components to determine the total heating/cooling load.

3. Importance of Load Calculation

Details: Proper load calculation prevents system oversizing (which reduces efficiency and increases costs) and undersizing (which leads to poor performance). It's essential for energy-efficient building design.

4. Using the Calculator

Tips: Enter each component in BTU/h. For detailed calculations, use Manual J or other professional methods. This calculator provides a basic estimate.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between heating and cooling load?
A: Heating load considers heat loss in winter, while cooling load considers heat gain in summer. Different components may dominate in each case.

Q2: How accurate is this simplified calculation?
A: This provides a rough estimate. Professional calculations consider more factors like solar gain, thermal mass, and local climate data.

Q3: What are typical BTU/h values?
A: Residential systems typically range 12,000-60,000 BTU/h, but vary greatly with building size and insulation.

Q4: Should I add a safety factor?
A: Professional calculations include appropriate factors. For this estimate, adding 10-20% may account for uncertainties.

Q5: What about latent vs sensible heat?
A: This calculator combines both. Detailed calculations separate them as they affect equipment selection differently.