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Heat Pump Planner

Size, cost and run your heat pump.

Answer five questions to see the right size unit for your home, the installed cost after the £7,500 BUS grant, and how running costs compare to your current boiler.

How the sizing actually works

BEDROOM15°

A cold house on a still January morning. Before the survey, the only thing that exists is the heat the building is losing.

What the house demands on the worst day

Heat loss on a still January morning sets the peak; the system has to meet that day, not the average. Floor area, insulation and exposure decide most of it before any unit is chosen.

What the fabric can take off the top

Loft insulation, draught-proofing and better glazing shrink the peak before the surveyor visits. Every kilowatt removed here removes a kilowatt the heat pump has to deliver forever.

What size unit then makes sense

Once demand is honest, a modulating heat pump can be specified close to peak rather than oversized for safety. Smaller, gentler, quieter; and meaningfully cheaper to run.

Your home

Fill in the form to see your sizing and cost.