1. What is Heat Load Calculation?

Definition: Heat load calculation determines the amount of heating or cooling required to maintain comfortable conditions in a space.

Purpose: It helps HVAC professionals and building designers properly size heating and cooling systems for optimal performance and energy efficiency.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( U \) — U-value (thermal transmittance) in W/m²K
• \( A \) — Area of the surface in m²
• \( \Delta T \) — Temperature difference between inside and outside in Kelvin
• \( \text{Internal Gains} \) — Heat generated by occupants, equipment, and lighting in Watts

Explanation: The formula calculates heat loss through building elements and adds internal heat sources to determine total heating requirements.

3. Importance of Heat Load Calculation

Details: Accurate heat load calculations ensure proper HVAC system sizing, energy efficiency, and occupant comfort while preventing system over-sizing or under-sizing.

4. Using the Calculator

Tips: Enter the U-value (check building specifications), surface area, temperature difference, and any internal heat gains. All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical U-value for walls?
A: Modern insulated walls typically have U-values between 0.1-0.3 W/m²K, while older buildings may be 1.0-2.0 W/m²K.

Q2: How do I determine ΔT?
A: Subtract the outdoor design temperature from the desired indoor temperature (e.g., 20°C inside and -5°C outside gives ΔT = 25K).

Q3: What are typical internal gains?
A: People generate about 100W each, computers 150-300W, and lighting 10-20W per m² depending on type.

Q4: Should I calculate for each room separately?
A: Yes, for best results calculate heat loads for each room as conditions may vary significantly.

Q5: Does this include ventilation heat loss?
A: No, this is only for conductive heat loss through surfaces. Add ventilation losses separately if needed.