Save up to 30% energy with the new hot water tank.

A hot water tank that saves space and reduces energy consumption by up to 30%: now available from Hoval. The VarioVal® layers the water according to the temperature, helping the homeowner to save energy.

In a calm, still lake, the water forms layers with different temperatures. Cold water is heavier and sinks down while warm water is lighter and rises up. The new VarioVal® hot water tank utilises this physical principle: it layers the water based on its temperature with the warmest water at the top and the coldest at the bottom. This layering means that, rather than having to heat the entire contents of the tank to the maximum temperature, only the much smaller top layer needs to be heated to this level. It stands to reason that this significantly reduces the energy requirements of the overall heating system while improving its efficiency considerably. This has been proven in tests conducted by an independent institute from Rapperswil in Switzerland.

Hot water in next to no time – with impeccable hygiene standards

The VarioVal® provides hot water for heating as well as drinking water for the bathroom and kitchen. The necessary drinking or domestic water is heated quickly via a heat exchanger. As the drinking water is not left standing in the heat exchanger and the water is heated quickly, dangerous legionella bacteria have no chance of survival. The hot water used for personal washing, for example, meets the highest hygiene standards. Alongside hygiene, there are also benefits in terms of efficiency. There is no need to store large volumes of drinking water and, as a result, there are no heat losses.

Saving space with a two-in-one design and fittings on the tank

As the VarioVal® provides both heating water and drinking water, it frees up space that would otherwise be taken up by a second tank. There is also more space available on the wall. The installer can mount the fittings required for the heating and hot water system on the tank itself. In this way, the heating system becomes a compact unit.

Combination options – including renewable energy sources

The Hoval VarioVal® hot water tank is available in various versions. It can be combined with a heat pump and with thermal solar collectors. Alternatively, the VarioVal® can help to save energy when used in conjunction with a gas or oil condensing boiler.


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Picture: Hoval-VarioVal.jpg

By layering the water according to its temperature, the new VarioVal® hot water tank can reduce energy consumption by up to 30%.


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