A heat pump moves heat from outside into the home and usually delivers it through radiators, underfloor heating or warm air. It performs differently from a boiler: steady operation at lower water temperatures is often part of the design.\n\nSuitability depends on heat loss, insulation, emitters, available outdoor space, noise constraints and the existing hot-water arrangement. A proper survey and heat-loss calculation matter more than a rule of thumb based only on floor area.\n\nAsk what flow temperature the design assumes, whether radiators need changing, where the outdoor unit and cylinder will go, how controls will work, and what seasonal performance has been estimated.\n\nRunning cost comparisons need the proposed efficiency, electricity tariff and the fuel being replaced. Be cautious of guarantees based on headline efficiency alone.\n\nEnergy Saving Trust’s independent guides cover the technology, installation questions and consumer considerations in more depth.