1. What is a Heat Loss Calculator?

Definition: This calculator estimates the heat loss from a building or surface based on U-value, surface area, temperature difference, and additional losses.

Purpose: It helps HVAC professionals and engineers determine heating requirements for buildings and systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Total heat loss (Watts)
• \( U \) — U-value (W/m²K)
• \( A \) — Surface area (m²)
• \( \Delta T \) — Temperature difference (Kelvin)
• \( \text{losses} \) — Additional heat losses (Watts)

Explanation: The formula calculates conductive heat loss through building elements plus any additional losses from ventilation, infiltration, etc.

3. Importance of Heat Loss Calculation

Details: Accurate heat loss calculations ensure proper sizing of heating systems, energy efficiency, and occupant comfort.

4. Using the Calculator

Tips: Enter the U-value of the building element, surface area, temperature difference between inside and outside, and any additional losses. All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is U-value?
A: U-value measures how well a building element conducts heat. Lower values mean better insulation.

Q2: How do I determine ΔT?
A: Subtract the outside design temperature from the desired indoor temperature (both in °C or K).

Q3: What are typical U-values?
A: Modern walls: 0.15-0.3 W/m²K, Windows: 1.0-2.8 W/m²K, Roofs: 0.1-0.25 W/m²K.

Q4: What should I include in additional losses?
A: Ventilation losses, air infiltration, thermal bridging, and system inefficiencies.

Q5: How does this relate to heating system sizing?
A: The total heat loss (Q) indicates the minimum heating capacity needed for the space.