The Cold Weather Myth
One of the most persistent myths about heat pumps is that they don't work in cold weather. This misconception stems from older technology that struggled in freezing temperatures. Modern heat pumps are a completely different story.
How Modern Heat Pumps Handle Cold
Today's air source heat pumps are designed to work efficiently down to -15°C to -25°C, depending on the model. This covers 99% of UK winter weather conditions. They use advanced refrigerants and compressor technology that functions effectively even when it's freezing outside.
In Scandinavia, where winter temperatures regularly drop below -20°C, heat pumps are the dominant heating technology. If they work in Norwegian winters, they'll certainly work in British ones.
Performance in Typical UK Winters
The UK's mild winters (average 3-7°C) are actually ideal for heat pump operation. At these temperatures, a quality heat pump maintains a coefficient of performance (COP) of 3.0 or higher, meaning it delivers three units of heat for every unit of electricity consumed.
What About Extreme Cold Snaps?
During the rare occasions when temperatures drop below -5°C, heat pump efficiency decreases slightly but they continue to provide adequate heating. Some systems include backup electric heating elements for extreme conditions, though these are rarely needed in the UK.
The Defrost Cycle Explained
In freezing conditions, you might notice your heat pump occasionally running in reverse for a few minutes. This defrost cycle removes ice buildup from the outdoor coil and is completely normal. It typically occurs every 30-90 minutes during sustained freezing weather.
