1. What is a Heat Pump Heat Loss Calculator?

Definition: This calculator estimates the heat loss (Q) through a building element based on U-value, surface area, and temperature difference.

Purpose: It helps HVAC professionals and homeowners properly size heat pumps by determining the heat loss that needs to be compensated.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Heat loss (Watts)
• \( U \) — U-value (W/m²·K)
• \( A \) — Surface area (m²)
• \( \Delta T \) — Temperature difference between inside and outside (°C)

Explanation: The formula calculates how much heat is lost through a building envelope component under specific conditions.

3. Importance of Heat Loss Calculation

Details: Accurate heat loss calculation ensures proper heat pump sizing, energy efficiency, and comfortable indoor temperatures.

4. Using the Calculator

Tips: Enter the U-value of the building element, its surface area, and the design temperature difference. 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 0.15-0.30 W/m²·K, while older walls may be 1.0-2.0 W/m²·K.

Q2: How do I find the ΔT for my location?
A: Subtract your winter design outdoor temperature from desired indoor temperature (usually 20-21°C).

Q3: Should I calculate for each room separately?
A: For whole-house heat pump sizing, calculate heat loss for all external surfaces and sum the results.

Q4: Does this account for air infiltration?
A: No, this calculates conductive heat loss only. Add 10-20% for typical air infiltration losses.

Q5: How does this relate to heat pump sizing?
A: Total heat loss determines the minimum capacity needed from your heat pump at design conditions.