1. What is a Heat Calculator for Room?

Definition: This calculator estimates the heat energy required to maintain a room at comfortable temperature based on heat loss through surfaces and ventilation.

Purpose: It helps HVAC professionals, architects, and homeowners determine heating system requirements for spaces.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Heat requirement (Watts)
• \( U \) — U-value (heat transfer coefficient, W/m²K)
• \( A \) — Surface area (m²)
• \( \Delta T \) — Temperature difference between inside and outside (Kelvin)
• Ventilation Loss — Additional heat loss from air exchange (W)

Explanation: The formula calculates conductive heat loss through surfaces and adds ventilation heat loss for total heating requirement.

3. Importance of Heat Calculation

Details: Proper heat calculation ensures energy-efficient heating system sizing, prevents under/over heating, and reduces energy costs.

4. Using the Calculator

Tips: Enter the U-value of surfaces, total surface area, temperature difference (indoor - outdoor), and any additional ventilation heat loss. All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical U-value for walls?
A: Modern insulated walls: 0.2-0.3 W/m²K, older walls: 1.0-1.5 W/m²K, single-pane windows: ~5.0 W/m²K.

Q2: How do I estimate ventilation loss?
A: For residential spaces, add 10-20% of conductive heat loss or use air changes calculation.

Q3: What temperature difference should I use?
A: Use the difference between desired indoor temperature and coldest expected outdoor temperature.

Q4: Should I calculate for each surface separately?
A: For more accuracy, calculate walls, windows, roof, and floor separately with their own U-values and sum the results.

Q5: Does this include thermal mass effects?
A: No, this is a steady-state calculation. Thermal mass effects require more complex dynamic modeling.