The novolto immersion heater can use surplus solar power for water heating with a supported measurement setup.
Smart water heating
Use surplus solar power for water heating. Installation requirements depend on your tank, electrical installation and local regulations.
Reduce conventional energy use
Using surplus solar power for hot water can reduce gas or oil consumption. Savings depend on available surplus solar power, hot-water demand, your existing heating system and local energy prices, including any export payments you would otherwise receive.
Local or cloud-based control
Use our app with a supported measurement solution, or integrate local control through MQTT with a suitable system such as Home Assistant. Check the requirements of your chosen integration before purchasing.
Do you have a photovoltaic system and also use gas or oil for your hot water?
The novolto immersion heater is the simplest way to use your energy from the roof for hot water generation.
When the sun is shining and your own requirements are met, the surplus is used for heating.
Precise control: Uses your surplus solar power continuously and efficiently starting at 20 watts.
Smart integration: Use a supported cloud connection or integrate local control through MQTT and a suitable system such as Home Assistant. Check the setup requirements before purchasing.
Installation requirements depend on your storage tank, electrical installation and local regulations. Follow the installation and operating manual and use a qualified installer where required.
novolto P2300 (2.3 kW immersion heater)
Suitable for compatible hot-water and buffer tanks
Automatically use surplus solar power
Save gas and oil immediately
Install according to the manual and local requirements
30-day trial with money-back guarantee
Shipping costs shown before payment

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Frequently asked questions
Can I install the smart immersion heater myself?
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Self-installation is only appropriate if your tank and electrical setup are suitable and local rules allow it. Follow the installation manual. Use a qualified installer where required or if you are unsure.
Requirements:
- 1.5" socket is present on the storage tank (or flange with socket)
- Power outlet nearby
Tools:
- Open-end wrench or pipe wrench
- Sealant (Teflon tape or hemp with sealing paste)
Essential steps:
- Switch off the heating system
- Shut off the cold water supply
- Release the pressure (open a higher-situated draw-off point, such as a water tap)
- Drain water down to the installation height
- Insert the immersion heater into the socket, screw in with a thread seal, and align it straight
- Refill with water and check for leaks
- Put the heating system back into operation
- Connect the immersion heater to the power outlet
How does the smart immersion heater work?
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The smart immersion heater is installed in your home's hot water storage tank, where it functions as an auxiliary heater. Electricity is converted into heat for your domestic hot water. To the extent that you use electricity for your hot water, you save on heating gas or oil. It is most effective to operate the smart immersion heater in conjunction with a photovoltaic system. Our smart immersion heater uses exclusively the excess electricity from your photovoltaic system that you would otherwise feed into the grid. This way, you not only save gas or oil but also increase your self-consumption.
Why should I use the smart immersion heater?
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With the smart immersion heater, you immediately increase the benefits of your photovoltaic system and extend the service life of your heating system. Instead of feeding electricity into the grid, you can use it to heat your domestic water for a large part of the year and give your heating system a break. This increases your self-consumption rate, avoids emissions, and saves your heating budget.
What is the difference between a smart immersion heater and solar thermal energy?
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A solar thermal system uses solar energy to heat domestic hot water and/or heating water. A photovoltaic system generates electricity for use in your own home – excess power is generally fed into the grid. The smart immersion heater absorbs this surplus electricity and uses it to heat your domestic water.
What are the requirements I need to meet?
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Suitable for compatible hot-water and buffer tanks. Check the tank manufacturer's approval, connection, installation space and material requirements before purchase.
To determine the available power for the immersion heater, you need a device that knows whether surplus electricity is currently being fed in. Our app connects to the device and transmits the values to the immersion heater. The novolto immersion heater is compatible with Shelly energy meters with Shelly Cloud access, Tibber Pulse IR and PowerOpti from PowerFox. We are continuously working to connect more providers.
Automatic surplus solar power control requires a supported measurement solution, such as a compatible Shelly device, Tibber Pulse or poweropti, or a suitable system connected through MQTT. Check that your chosen solution works with your electricity meter and is supported by novolto before purchasing.