Storage water heaters

What is a storage water heater?

A storage water heater, often called a boiler, is an appliance fitted with a tank in which water is heated and held at temperature, ready to use. Unlike instantaneous models, it doesn't heat the water at the moment of draw-off but stores it, ensuring a constant reserve even when you open several taps at the same time.

What litre capacity to choose

The main criterion is the litre capacity of the tank, to be chosen according to the number of people and bathrooms:

• 10 and 15 litres: ideal for the kitchen sink or a small cloakroom.
• 50 and 80 litres: suited to one or two people with a daily shower.
• 100 litres: designed for families of three or four people.
• 150 litres and above: for large households or homes with several draw-off points.

The larger the tank, the more hot water you have available before you have to wait for a new heating cycle.

When storage is better than instantaneous

The storage boiler is worthwhile when several outlets are needed at the same time, when the electrical system can't handle the power peaks of instantaneous units, or where a suitable gas connection is missing. If instead you want hot water at a single tap and without a tank to keep warm, an instantaneous electric water heater may be more suitable. For a full comparison, start from the general water heaters page.

Energy class and tank insulation

With storage, efficiency depends heavily on the insulation of the tank: good insulation reduces heat loss between uses, lowering consumption. The energy class on the label accounts for exactly this, so it's worth comparing it together with the available offers. For maximum efficiency, also consider heat pump water heaters, which use the air to heat the water in the tank.

Installation and maintenance

Installing an electric storage boiler is generally simple and requires the plumbing connection and a suitable socket. Over time it's important to check the protective anode and plan regular maintenance to limit limescale in the tank. If the hot water also serves the heating system, consider integrated solutions such as wall-hung boilers.

The best brands available

In this category you'll find the Ariston range, with models covering small to large capacities. Prices start at around 360 euro up to the higher-capacity solutions, all ready to ship with official warranty and spare parts available.

Related solutions

• All water heaters
• Electric water heaters
• Heat pump water heaters
• Condensing boilers

Frequently asked questions