1. What is HVAC Load Calculation?

HVAC load calculation determines the heating and cooling capacity needed for a space. It accounts for heat gain from various sources and ventilation requirements to properly size HVAC equipment.

2. How Does the Calculator Work?

The calculator uses the basic load equation:

Where:

• \( Heat Gain \) — Total heat gain from occupants, equipment, lighting, and solar radiation (BTU/hr)
• \( Ventilation \) — Heat load from required outdoor air ventilation (BTU/hr)

Explanation: The equation sums all heat sources that the HVAC system must compensate for to maintain desired indoor conditions.

3. Importance of Load Calculation

Details: Proper load calculation prevents equipment oversizing (which reduces efficiency) and undersizing (which leads to inadequate comfort). It's essential for energy-efficient system design.

4. Using the Calculator

Tips: Enter heat gain and ventilation values in BTU/hr. These should be calculated from detailed heat gain analysis or using more comprehensive load calculation methods.

5. Frequently Asked Questions (FAQ)

Q1: What's included in heat gain?
A: Heat gain includes solar radiation through windows, heat from occupants, appliances, lighting, and heat conduction through building envelope.

Q2: How is ventilation load calculated?
A: Ventilation load is calculated based on required air changes and the enthalpy difference between outdoor and indoor air.

Q3: What's a typical load for a residential space?
A: Residential cooling loads typically range from 12,000-60,000 BTU/hr depending on size, insulation, and climate.

Q4: Are there more detailed calculation methods?
A: Yes, methods like Manual J (residential) or Manual N (commercial) provide more comprehensive load calculations.

Q5: Why not just use square footage rules?
A: Square footage rules often lead to significant oversizing. Proper load calculations account for all heat sources and building characteristics.