AC Reheating – for 30l water heater


incl. 19% VAT


Hot water even on the darkest days with very little sunlight. The 18V power supply unit reheats the water if there is not enough photovoltaic power available.

If the water temperature of the boiler falls below the set minimum temperature, the power supply unit is automatically switched on by the boiler. As a result, the water is heated using electricity from the socket.

Setting the minimum temperature
With the buttons on the boilers, a minimum temperature can be set within a very short time. This minimum temperature can be freely configured between 5°C and 65°C in 5°C steps. For example, a minimum water temperature of 35°C can be set. If the water temperature falls below the set minimum temperature, the mains unit is automatically switched on by the boiler. The water is heated via mains current.
As soon as the set minimum temperature is reached, the reheating process is automatically stopped again.

PV electricity always has priority
The photovoltaic boiler always uses as much photovoltaic electricity as possible.
If the water temperature falls below the set minimum temperature while electricity is being generated by the photovoltaic modules, then all the photovoltaic electricity is always used first. If not enough electricity is available from the photovoltaic modules while the water temperature is below the minimum, electricity is drawn from the grid in parallel.

The photovoltaic modules connected to the boiler currently supply 100W of power. At the same time, a mains unit with 140W output is connected to the 30-liter boiler. The current water temperature is 25°C. The set minimum temperature is set to 35°C.
As the minimum temperature is lower than the current water temperature, the reheating is activated. The mains unit is automatically switched on by the boiler. The power supply unit will heat the water in the boiler with a power of 40W, as an additional 100W from the photovoltaic modules is used.
As soon as the power of the photovoltaic modules exceeds the power of the power supply unit, the power supply unit is deactivated.

Product Highlights

Max. solar energy

Photovoltaic power always has priority. This keeps the electricity bill as low as possible.

Always hot water

Hot water even on the darkest days.

Automatic reheating

Automatic reheating as soon as the temperature falls below a minimum.

Connecting the power supply and setting the minimum temperature

Work time: 1 minute
The power supply unit is connected via a simple plug-in connection. Installation is intuitive. No electrician is needed.

1. Step: The power supply unit has to be plugged into the bottom of the boiler and into the socket

2. Step: The second step is to set the minimum water temperature. This is done via two buttons directly on the boiler. The configuration is very simple and is explained in detail in the operating instructions supplied.

More Highlights

1 minute

Installation in less than a minute.

Intelligent PV power detection

Intelligent PV power detection to ensure maximum solar yield.

Heating times

The heating times of the boiler depend on the power of the power supply unit and the volume of the boiler. Below you will find a list of recommended power supply units. However, other power supply unit/boiler combinations can also be chosen as required.

Recommended power supply units:

    • 10 liter boiler: 12V power supply unit with 62W heating power
    • 30 liter boiler: 18V power supply unit with 140W heating power
    • 80 liter boiler: 24V power supply unit with 240W heating power

Water heating per hour

Boiler volume:

10 Liter

30 Liter

80 Liter

12V PSU*:

18V PSU*:

24V PSU*:


6 °C/h

12 °C/h

22 °C/h

2 °C/h

4 °C/h

7 °C/h

0,7 °C/h

1,5 °C/h

2,7 °C/h

*Power Supply Unit

Scope of delivery

– 1x 18V power supply unit
– 1x operating and assembly instructions

Download area more documents:

(data sheets, manufacturer’s instructions, declarations of conformity, installation videos, circuit diagrams, etc.)

Additional information


External Power Supply Unit 60W, External Power Supply Unit 140W