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Living with a heat pump: schedules, hot water and bills

A heat pump works best warming the home steadily at a low water temperature, rather than in short, hot bursts like many boilers. There is no single best schedule; start with your installer's settings and adjust gradually.

Updated 3 October 2026 · energy.org.uk editorial team

Heating

  • Run it steadily. Long periods at a lower flow temperature are usually more efficient than switching on and off. Large setbacks overnight can mean it runs hard to catch up in the morning.
  • Use weather compensation, if your controls have it. It lowers the water temperature on milder days.
  • Radiators feel warm, not hot. That is normal if rooms reach the temperature you set.
  • Keep thermostatic radiator valves open in the main rooms, so water can flow; use the main controls to set the temperature.

Hot water

  • Heat the cylinder at set times, ideally when electricity is cheaper if your tariff has a cheap period.
  • Many systems also heat the cylinder to a higher temperature from time to time to control legionella. Ask your installer how yours is set.
  • A higher hot water temperature uses more electricity, so don't set it higher than you need.

What is normal

  • In cold, damp weather, the outdoor unit defrosts itself now and then. You may see steam and hear it change sound; this is normal.
  • It runs for longer in cold weather.
  • Running costs are highest in the coldest months.

Bills and tariffs

Most of a heat pump's use is in winter. A tariff with cheaper rates at some times of day can cut costs if you heat water and, where it suits, warm the home in those times. Compare options in heat pump tariffs.

Check

What to check first

  • Your controls' settings: flow temperature, weather compensation and hot water times.
  • Your electricity use, from your smart meter or the heat pump's app, month by month.
  • Your installer's handover notes and design estimate.

Do

Practical next steps

  1. Ask your installer to explain the controls and leave written settings.
  2. Change one setting at a time and give it a few days.
  3. Compare your use with the estimate in the heat pump calculator.
  4. Book the servicing your warranty requires.

Take care

Important limitations

  • If rooms don't get warm, or costs are far above the estimate, contact your installer; the design or settings may need changing.
  • We don't give one schedule for every home; it depends on the house, the system and how you live.

Related tools and guides

Sources

Official sources checked 3 October 2026.