Water heaters for the needs-based supply

The demand for domestic hot water is completely different in every household. The most important influencing factors include the number of residents and bathing or showering habits. For example, if three members of a family need to leave for work and school at the same time, a large quantity of hot water needs to be continuously available for the shower, without keeping anyone waiting. If only one person needs domestic hot water in the same period of time, the demand is usually different.

Those who prefer a bath will also want to have enough hot water to fill the tub. The water heater should also be able to provide sufficient water if, in an apartment building for example, hot water is drawn from more than one outlet at the same time.

Viessmann Vitocell  DHW cylinders fulfil these requirements in every respect and can also meet every aspiration where the equipment level is concerned. The appliances can be combined with different heat generators. Vitocell DHW cylinders are just as suitable for dual mode operation with a condensing boiler as they are for operation with an environmentally responsible heat pump or a solid fuel boiler. In all instances, the installation of a solar thermal system is recommended to allow you to save energy and heat the water at no cost.

DHW heating for every need

Domestic hot water can be produced in different ways. If the domestic hot water is produced centrally, a connection to an existing heating system is indispensable. In that case, the heat generator not only provides space heating but also ensures that domestic hot water is available at all times of the day.

In addition, there is also the option of decentralised DHW heating. Electric DHW systems such as Viessmann Vitotherm are often used for this purpose. These are not connected to the heating system and can be easily retrofitted. It does not matter whether the appliances are storage water heaters or instantaneous water heaters.

Water heaters based on the instantaneous water heating principle

A Viessmann Vitotrans 353 freshwater module can also be used alongside a central or decentralised DHW heating system. These modules complement the heating water buffer cylinders in the Vitocell product range. The domestic hot water is heated conveniently and hygienically using the instantaneous water heating principle. No DHW is stored. Instead, the fresh water is heated to the required temperature level with the energy from a heating water buffer cylinder. These cylinders can be combined with a range of different systems.

The different versions of Viessmann DHW cylinders

Viessmann DHW cylinders are characterised by their high efficiency, diversity and ease of installation. The units are available in different versions:

• Vertical DHW cylinders (Vitocell 100-L, Vitocell 100-V and Vitocell 300-V)
• DHW cylinder below the boiler (Vitocell 100-W)

The cylinder capacity ranges from 120 to 1000  litres, depending on the model. This makes Viessmann DHW cylinders suitable for use not only in detached houses, but also in buildings with a high DHW demand.

Dual mode DHW cylinders for solar thermal systems

A dual mode DHW cylinder is an indispensable component of a solar thermal system. This is because it absorbs the heat generated by the system and transfers it to the water. Viessmann's dual mode DHW cylinders each have two separate internal indirect coils and heat the water via both the solar thermal system and a boiler. This ensures that the required temperature level is always maintained. The cylinders are made of steel with Ceraprotect enamel coating (Vitocell 100-V, Vitocell 100-W, Vitocell 100-B, Vitocell 100-U) or stainless steel (Vitocell 300-V, Vitocell 300-H, Vitocell 300-B).

The quality of the inner surface of the DHW cylinder is crucial to providing DHW hygienically. For this reason, Viessmann relies on two high quality materials: Ceraprotect enamel coating for safe, lasting protection against corrosion – applicable to the Vitocell 100 range. Stainless steel – used for the Vitocell 300 range – which satisfies the highest hygiene demands.

Heating water buffer cylinders for efficient use of thermal energy

A heating water buffer cylinder has the task of temporarily storing the surplus energy produced by a heat generator and only releasing it back to the heating system when required. The stored energy can be used to heat the heating circuits or the domestic hot water. Heating water buffer cylinders such as the Vitocell 120-E or Vitocell 140-E are also factory-equipped for dual mode operation with a heat pump or a solar thermal system. The appliances can hold up to 2000  litres.

DHW cylinders in two energy efficiency classes

By default, most DHW cylinders with a cylinder capacity requiring identification (up to 500  litres) meet energy efficiency class B. For selected cylinder types, it is also possible to choose between energy efficiency class A or B. Cylinders in class A are thermally insulated with an additional vacuum panel which reduces heat losses and therefore energy costs.