an underestimated alternative

After gas heating systems, oil heating systems are the type used most frequently in Germany

Around 6 million oil heating systems reliably provide German households with a comfortable standard of living. Advanced oil heating systems are economical, efficient, and environmentally responsible. Thanks to resource-saving innovations, these systems are now state of the art.

Enstpanntes Kochen in der Küche
Oil heating systems make for comfortable and pleasant indoor environments in Germany. And that's nice to come home to.

The core of any oil heating system is the boiler. The core of any oil heating system is the boiler. Older oil boilers no longer correspond to the latest engineering standards. That means that valuable energy is being wasted. A new, advanced oil boiler can help you tremendously increase the efficiency of your heating system, improve convenience through the control systems and lower your heating costs.

  • Benefits

    • Advanced condensing technology enables the highly efficient use of fuel.
    • The German Kreditanstalt für Wiederaufbau (Reconstruction Loan Institution; KfW) subsidises advanced oil heating systems at 10 % of the investment costs.
    • Your choice of oil supplier.
    • Oil can be purchased in advance during periods when prices are low.
    • No connection to the gas mains is required.
    • Easy to combine with solar.
    • Saves space (only 1 m2 required for boiler and controller; 3-4 m2 for the oil tank).
    • Proportional use of biofuel oil possible in some cases. 
  • Drawbacks

    • Oil is an imported fuel.
    • Petroleum is a limited resource.
    • Space is required for the oil tank (exception: underground tanks).
    • Relatively high CO2 emissions on combustion.

The amount of heat energy used for energy recovery can be seen in the flue gas temperatures, for one thing: whilst older, low temperature appliances produce flue gases at about 140-200 °C, condensing boilers emit gas that is only around 50 °C. Here we'll show you what this means for the modernisation of older systems.

The heat recovery feature in condensing boilers results in much better energy efficiency with condensing appliances compared to conventional boilers. In such systems, the heat escapes unused up the chimney. The conversion from a conventional boiler to heating using innovative condensing technology is an investment that will pay dividends over the long term.


Advanced oil condensing boilers and solar thermal systems work perfectly together. When you combine them, you can save up to 30 % on fuel oil costs.

Solar thermal systems give you support from the sun for your DHW heating or can also assist as central heating backup. In addition to an oil heating system, you will need a solar thermal system. This consists of rooftop solar collectors and a cylinder.

Solarkollektoren auf dem Dach eines Hauses
Use energy from the sun to heat your home and hot water – it's cheaper and more environmentally responsible.

But what about when the sun isn't shining? In that case, your oil heating system automatically makes up the difference. A solar thermal system can provide up to 60 % of the energy for DHW heating and up to 20 % of the energy for your heating needs – at almost no cost and with an absolutely clear environmental conscience. The sun isn't the only one smiling about it.


At first glance, oil is somewhat more expensive than gas and emits more CO2. Nevertheless, a gas heating system is not always the best choice.

If you already have an oil heating system, then the most cost effective option is to simply replace the boiler. Ideally with condensing technology. The KfW is promoting conversion to advanced oil condensing boilers with subsidies of 10 % – up to €5000 – of the eligible costs. Switching from oil to gas means having the oil tank professionally removed, and if your home is not connected to the gas mains, this incurs additional costs as well. These factors can quickly cancel out the potential savings on fuel.

If you are planning a new build and are considering an oil heating system, be sure to keep the oil tank in mind. If you don't have enough space above ground for the tank, an underground tank is a good solution. However, underground tanks are more expensive to purchase and require a permit.


Have you chosen a new oil condensing boiler? Then there are a few points you should note before starting with the installation.

In order for the installation of your new heating system to be eligible for a subsidy from the KfW [Germany], you must apply prior to starting the modernisation work. Then you can look forward to a subsidy of 10 %, up to a maximum of €5000. Costs that can be subsidised include the disposal of the old system, chimney modernisation and the replacement of radiators. When modernising chimneys, remember that the temperatures of the flue gas is lower when using an advanced condensing boiler than with older appliances. This may lead to condensation in the chimney or flue and cause damage. You can prevent this by installing a plastic or stainless steel pipe in the chimney. Replacing a heating system is the ideal opportunity to check your DHW cylinder. The water hardness, age and usage may make a replacement for hygienic purposes advisable.

Together with an expert, you can quickly identify the heating system best suited to your needs. Get some good advice without any obligation.