Electric storage water heaters?

Electric storage water heaters? What are they? Electric storage water heaters are water heating appliances that use electricity to heat and store hot water in an insulated tank, ready for use when required. In simple terms, they heat a set volume of water and keep it hot until it is needed at taps, basins, sinks, showers or other domestic hot water outlets.

In the UK, electric storage water heaters are commonly used in flats, apartments, offices, workshops, shops, commercial washrooms, small homes and properties where gas or oil is not available. They are also useful where only local hot water is required, such as for a kitchen sink, hand wash basin or remote washroom.

They usually work by using an immersion heater or electric heating element inside the cylinder or tank. Once the water reaches the set temperature, the thermostat switches the heater off. As hot water is drawn off, cold water enters the unit and is reheated.

Electric storage water heaters are available in different types and sizes. Small undersink units may only store a few litres of hot water, while larger electric cylinders can store enough water for baths, showers and whole-property hot water demand. They can be vented or unvented, depending on the design. Unvented models connect directly to the mains water supply and can provide mains pressure hot water, provided the incoming pressure and flow rate are suitable.

Our unvented range of electric hot water storage heaters for normal residential use are detailed here – Unvented electric hot water storage heaters in duplex stainless steel from 80 to 500 litre

Or alternatively, our commercial range with capacities from 80 to 6,000 litres with larger power inputs up to 400 kW are detailed here – Commercial electric water heaters – unvented or vented 

The main benefits are simple installation, no flue, no gas supply, quiet operation and straightforward hot water storage. They can also be used with off-peak electricity tariffs, solar PV diverters or smart controls to help reduce running costs.

However, electric storage water heaters do have limitations. Once the stored hot water has been used, there is a recovery period while the unit reheats. They also have some standing heat loss, although modern well-insulated cylinders are designed to reduce this effect.

In simple terms, an electric storage water heater is an electrically heated hot water tank that stores domestic hot water for later use.