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Heat Pump Size Formula:
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Heat pump sizing determines the appropriate capacity (in kW) needed to efficiently heat your home. Proper sizing is crucial for energy efficiency, comfort, and system longevity. This calculator provides an estimate based on your home's floor area and heat loss characteristics.
The calculator uses this simple formula:
Where:
Explanation: The calculation converts the total heat requirement (in Watts) to kilowatts by dividing by 1000. This provides the estimated heat pump capacity needed.
Details: An undersized heat pump will struggle to heat your home, while an oversized one will short-cycle, reducing efficiency and lifespan. Proper sizing ensures optimal performance and energy savings.
Tips: Measure your home's total floor area accurately. The heat loss factor typically ranges from 50-100 W/m² (65 is average for UK homes). Well-insulated homes may use 50-60, while older properties may need 70-100.
Q1: Is this calculator suitable for all UK homes?
A: It provides a basic estimate. For precise sizing, consult a professional who can consider insulation levels, window types, and local climate.
Q2: How does this relate to monthly costs?
A: A properly sized heat pump runs more efficiently, reducing monthly energy costs. Oversized/undersized units increase operating costs.
Q3: Should I round up the calculated size?
A: Heat pumps come in standard sizes. Professionals typically recommend the next available size if your calculation falls between standard units.
Q4: Does this account for hot water needs?
A: No, this calculates space heating only. Add 1-2 kW if the heat pump will also provide domestic hot water.
Q5: How accurate is the heat loss factor?
A: For detailed assessment, a professional heat loss calculation is recommended, especially for older or unusually constructed homes.