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Air Source Heat Pump Size Calculator UK

Heat Pump Size Formula:

\[ \text{Size} = \frac{\text{Heat Loss}}{\text{COP}} \]

kW
dimensionless

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1. What is an Air Source Heat Pump Size Calculator?

Definition: This calculator determines the required size (in kW) of an air source heat pump based on your property's heat loss and the system's coefficient of performance.

Purpose: It helps homeowners and installers properly size heat pumps for UK properties to ensure efficient operation and avoid undersizing or oversizing.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \text{Size} = \frac{\text{Heat Loss}}{\text{COP}} \]

Where:

Explanation: The heat loss is divided by the COP to determine the heat pump size needed to maintain comfortable temperatures.

3. Importance of Proper Sizing

Details: Correctly sizing your heat pump ensures optimal efficiency, reduces running costs, extends system lifespan, and maintains comfort levels.

4. Using the Calculator

Tips: Enter your property's heat loss (from a heat loss calculation) and the expected COP (typically 2.5-4.0 for UK systems). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I find my property's heat loss?
A: A qualified energy assessor can perform a heat loss calculation, or you can use online tools with your property details.

Q2: What's a typical COP for UK heat pumps?
A: Most modern air source heat pumps have a COP between 3.0 and 4.0 under UK climate conditions.

Q3: Why does COP affect the size needed?
A: Higher COP means more efficient heat production, so a smaller unit can meet your heating needs.

Q4: Should I add a buffer to the calculated size?
A: It's common to add 10-20% capacity for extremely cold days and to account for potential calculation uncertainties.

Q5: Does this calculator account for hot water needs?
A: No, this calculates space heating requirements only. Add 0.5-1.5kW if the heat pump will also provide domestic hot water.

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