Should I turn my heat pump off at night or when I'm out?

Updated 29 September 2026

Short answer: usually not off. Letting the house drop a degree or two is fine, but a big drop means the heat pump has to run hot and hard to catch up, and that often lands at a pricier time.

With a boiler, turning off at night saves gas. A heat pump is different: warming a cold house quickly needs hotter water, which lowers its COP (heat out divided by electricity in), and the catch-up often falls in the morning when you want to be warm fast.

On Cosy Octopus, the bigger saving is usually timing. Warm the house a little more in the cheap periods, especially 1pm to 4pm, and let it coast through the 4pm to 7pm peak. Every home is different, so try one change at a time and compare weeks with similar weather.

In Snugdays: Schedule shows which of your times fall in cheap and peak rates, and Snugdays+ tells you after two weeks whether a change actually saved money.