1. What is Heat Pump Sizing?

Heat pump sizing calculates the appropriate capacity (in kW) needed to efficiently heat a UK home based on floor area and heat loss characteristics. Proper sizing is crucial for energy efficiency and performance.

2. How Does the Calculator Work?

The calculator uses the standard UK heat pump sizing formula:

Where:

• \( Area \) — Total floor area of the property in square meters
• \( Factor \) — Heat loss factor typically between 50-100 W/m²
• \( kW \) — Recommended heat pump capacity in kilowatts

Explanation: The formula converts the total heat requirement (in watts) to kilowatts by dividing by 1000.

3. Importance of Correct Sizing

Details: Properly sized heat pumps operate more efficiently, provide consistent comfort, and have longer lifespans. Oversizing leads to short cycling, while undersizing results in inadequate heating.

4. Using the Calculator

Tips:

• Measure total heated floor area (excluding garages/outbuildings)
• Use 50-70 W/m² for well-insulated homes
• Use 80-100 W/m² for average insulation
• Use 100-150 W/m² for poorly insulated or older properties

5. Frequently Asked Questions (FAQ)

Q1: What's a typical heat pump size for a UK home?
A: A 3-bed semi-detached house (85m²) typically needs 5-8kW, while a 4-bed detached (150m²) may need 10-14kW.

Q2: Should I get a professional assessment?
A: Yes, this calculator provides an estimate. A professional heat loss survey is recommended for accurate sizing.

Q3: Does property age affect the factor?
A: Yes, older properties generally have higher heat loss factors due to less insulation.

Q4: What about hot water requirements?
A: This calculator focuses on space heating. Add 1-2kW to the total if the heat pump will also provide hot water.

Q5: Are there other factors to consider?
A: Yes - ceiling height, window quality, ventilation, and local climate all affect sizing.