Electric instantaneous water heater

Thanks to rated outputs from 3.5 to 27 kW and a wide range of models, Vitotherm electric instantaneous water heaters can be used in almost any room. Find out in this section which appliance best suits your needs.

Simple installation and virtually maintenance-free
iF Design Award
With switchable output
Energy efficiency class: A

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With switchable output

For Vitotherm EI2, EI4 and EI3

Simple replacement

For all common instantaneous water heaters

Easy fixing system

With integral compensation for unevenness in the wall

Insertion aid

For the connecting cable

Comprehensive safety concepts

EI2 is eligible for subsidies

Energy efficiency class

Energy efficiency class: A

Vitotherm EI4 electric instantaneous water heater

Vitotherm electric  instantaneous water heater

Domestic hot water is needed all year round in this country, whether for a shower in the morning or for washing hands and feet. It can be produced with an electronic instantaneous water heater such as the Vitotherm  EI4 comfort instantaneous water heater. Appliances of this size –– including the Vitotherm E15 –– are small in terms of performance but the ideal solution for a guest toilet due to their extremely compact dimensions.

If a little more output is required, instantaneous water heaters for the kitchen such as the Vitotherm EI3 and Vitotherm EI4 are worth considering. Thanks to their minimal installed depth, they also fit under the sink. They reliably heat the tap water to the required temperature instantly, with total precision.

Benefits of electric instantaneous water heaters

In most cases, instantaneous water heaters run on electricity, which is already available. For the owner, this means easy installation on the one hand and quick commissioning on the other. In addition, only the water that is actually required is heated. This saves both energy and water. A further distinguishing feature of electric instantaneous water heaters is their virtually maintenance-free operation. This ensures DHW heating for years to come. If instantaneous water heaters are operated electronically, there are even more advantages.

Electronic instantaneous water heaters for  different applications

From hydraulically controlled mini instantaneous water heaters to fully electronic instantaneous water heaters: These appliances are available in a wide variety of types. They include comfort instantaneous water heaters for fast and efficient provision of domestic hot water, such as the Vitotherm EI2. This model offers multiple functions, including child lock, automatic water volume control and wellness shower programs.

With a minimal installed depth, yet sufficient rated output, comfort appliances such as the Vitotherm EI4 and Vitotherm EI6 can be used anywhere. In rooms with a very low DHW demand, such as guest toilets, a mini instantaneous water heater such as the Vitotherm EI5 is the appliance of choice.


Tech Talk – Vitotherm and Vitoplanar

Design Plus Award for Vitotherm

The Vitotherm electric instantaneous water heaters have won an iF Design Award.

Product overview

Below you will find a selection of the Vitotherm product range with the relevant key data. Further information on the individual products is also available in the  Electric heating systems brochure (PDF, 656  KB)   and in the  datasheets in our ViBooks database.

Vitotherm EI2 – fully electronic with colour display and 4S function

Vitotherm EI2

The fully electronic Vitotherm  EI2 instantaneous water heater offers excellent DHW convenience. The appliance is designed for outputs of 18, 21 and 24  kW. A processor-controlled motorised valve provides accurate, constant water temperature (30 to 60  °C) at the maximum flow rate.

The 4S function includes an inlet and outlet temperature sensor, flow sensor for continuous automatic output adjustment and a motorised valve. It also features wellness shower programs, eco functions, programmable memory functions and automatic water volume control.

The multifunction display shows the temperature, flow rate, energy consumption and time. If the water temperature exceeds 42  °C, the display illumination changes from blue to red as a warning that the water is too hot. The child lock function, which takes effect at 43  °C, prevents unintentional adjustments. Electronic air bubble detection ensures consistently high DHW convenience. The energy consumption and volume of water can be read from the consumption display.  

Product cross-section Vitotherm EI2

Vitotherm EI4 – the all-rounder with 3S function

The electronically controlled Vitotherm EI4 instantaneous water heater combines the three output stages 18, 21 and 24  kW in one appliance. It is characterised by its variable temperature selection ranging from 30 to 55  °C. Permanent scald protection can be set to take effect at 43  °C.

This all-rounder with 3S function features inlet and outlet temperature sensors and a flow sensor for continuous output adjustment

Vitotherm EI6 – electronically controlled comfort instantaneous water heater with 2S function

The Vitotherm EI6 electronic instantaneous water heater with outputs from 18 to 27  kW is ideal for the bathroom. Its three-stage temperature selector switch which can be set to 30, 45 or 55  °C ensures the required temperature for bathing and showering at all times. The 2S function consists of an inlet temperature sensor and a flow sensor with output adjustment.

The Vitotherm  EI6 is the ideal choice for property development, replacing old appliances in apartment buildings, or modernisation projects. It can be installed remarkably quickly.

Vitotherm EI3 – electronically controlled compact instantaneous water heater with 3S function

Vitotherm EI3 –– compact and space saving.  Domestic hot water is constantly needed in the kitchen. The Vitotherm EI3 electronic instantaneous water heater with 3S function is ideally suited for this purpose. With outputs of 11 or 13.5  kW (switchable), it provides a water temperature that can be set to the nearest degree. The Vitotherm  EI3 is suitable for preheated water up to 70  °C. This compact instantaneous water heater can be used to reheat water that has already been preheated to 55  °C. The appliance features a multi stage electronic safety concept and integral scald protection.

With an installation depth of just ten centimetres, this compact and space saving appliance can be easily installed under a sink or hand basin. The Vitotherm  EI3 is secured directly to the wall through the back panel, for quick installation. Any unevenness can then be easily levelled out.

Vitotherm EI5 – hydraulically controlled mini instantaneous water heater

Vitotherm  EI5 –– DHW convenience in a mini format. The EI5 mini instantaneous water heater provides an efficient, hydraulically controlled and inexpensive supply of domestic hot water for a hand basin. It is the ideal solution for a guest toilet. The appliance is available with 3.5, 5.7 and 6.5  kW output ratings. It is suitable for undersink installation and for connection to any commercially available tap. The appliance is equipped with a flow switch and flow meter.

ViBooks – documentation & brochures

In our central, clearly laid out ViBooks database, you can quickly and easily find the operating instructions, data sheets and all kinds of brochures you need.