Electric Combi Boilers | Instant Hot Water & Central Heating — No Flue, No Gas

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An electric combi boiler combines central heating and instant domestic hot water in a single wall-mounted unit — with no need for a flue, gas supply, or separate hot water cylinder. They're quiet, compact, 100% efficient at point of use, and ideal for flats, apartments, smaller homes, or any property where gas isn't available or practical. Browse our range from trusted brands including EHC, Strom, Biasi, Elterm, EHS, E.C.A, and ThermoSphere — all available in a range of power outputs to suit different property sizes and electrical supplies. Choosing the Right Power Output — This Matters More Than You Think One of the most common mistakes when buying an electric combi boiler is underestimating how much power is needed for a satisfying hot water experience. The kW rating does two jobs simultaneously: heating your radiators and producing instant hot water on demand. When you open a hot tap or turn on a shower, the boiler switches to domestic hot water (DHW) mode and uses its full rated power to heat the water as it flows through. The amount of hot water an electric combi can produce depends entirely on its kW output and your incoming cold water temperature. As a rough guide, assuming a cold water inlet temperature of around 10°C and a desired output of 45°C (a ΔT of 35°C): 7kW produces approximately 2.9 litres per minute of hot water. This is a common source of frustration — many buyers choose a 7kW boiler expecting a decent shower and are disappointed. A standard shower typically needs at least 6–8 litres per minute, meaning a 7kW boiler on its own is unlikely to deliver a satisfying showering experience unless you're using a very low-flow showerhead or a thermostatic mixer set to a relatively low temperature. A 7kW boiler is better suited to properties where hot water demand is very low, such as a single-person flat with a bath or a system used primarily for central heating with minimal hot water draw. 11kW produces approximately 4.5 litres per minute — an improvemen