A broad introduction to heat sources, electricity use and the conditions that support good performance.
Core idea
A heat pump uses electricity to move heat from air, ground or water into a building. Because the delivered heat includes energy taken from the source, useful heat output can exceed electrical input. Performance improves when the source is favourable and the heating system can operate at lower temperatures.
What to recognise
- Air-source units exchange heat with outdoor air and must manage airflow, noise and defrost.
- Ground-source systems use buried collectors and need suitable land or boreholes.
- Lower building heat loss and suitable emitters reduce the required temperature lift.
- Stored hot water, controls and backup heat must be designed with the heating system.
- COP describes a point; seasonal performance includes changing conditions.
Apply it
When comparing a heat pump with an existing boiler, do not compare only appliance nameplate outputs. Compare building load, water temperatures, distribution changes, hot-water service, electricity supply, siting and expected seasonal energy. The design should explain how comfort is maintained at the cold design condition.
Keep the boundary clear
Heat pumps are not combustion appliances, but they still bring electrical, pressure, refrigerant, water-hygiene and planning duties. A broad awareness question should not be used to make an installation decision without a competent survey and current manufacturer data.
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