Direct Contact

+49 268 18 07-01

Domestic Engineering

Heating Oil Tanks

Oil Tanks made of plastic

As a pioneer in the manufacture and development of oil tanks made of plastic material, WERIT has over 50 years of expertise. Intensive research and ground-breaking innovations have made WERIT an idea provider for industry and trade. Qualified employees, state-of-the-art technology and constant quality control are today the guarantee of our market-driven, high-quality products, such as our surge tanks, transport containers and transport crates. In addition to the German and European markets, we export all over the world. Further information can be found in our extensive product range.


Product catalogue

Download catalogues, brochures and other printable material directly as PDF. Under Service Downloads, the PDF files are sorted for you according to the subject.


We would be pleased to provide you with non-binding advice on your solution from WERIT



Frequently Asked Questions

Heating oil tanks by WERIT

Yes, our double-walled heating oil tanks promise a very high quality standard and long service life. With regard to the CO2 emissions, oil condensing boilers consume up to 30% less energy. Using climate-neutral supplements (solar thermal energy or photovoltaic), the climate objectives of tomorrow are already being fulfilled today.

We are convinced of the quality and safety of our tanks. This is why we do not only follow the statutory warranty obligations, but our specialist wholesale customers and selected tank protection companies offer a 15 year guarantee on all double-walled Techno tanks. We grant a two year guarantee on technical accessories.

Being a pioneer in the manufacturing and development of plastic tanks, WERIT falls back on a know-how from more than 60 years in plastic processing. Qualified employees, the most modern technologies and continuous quality control are the guarantee seal of our high-quality products in line with the market today.

The sales take place exclusively via the sanitary and heating wholesale industry as well as selected tank protection companies and plant engineers. We would be pleased to name a competent partner near to you. 

Techno E and Techno K are both of our double-walled tank systems. They differ only in their form and dimensions. The manufacturing quality is identical. 

Setting up and connecting heating oil tanks

The ordinance on facilities for the handling of substances hazardous to water (AwSV) specifies that certain actions on heating oil tanks including all pipelines and safety equipment may only be carried out by companies that are able to verify a special qualification. They are called a "Specialist company according to the Water Act" or also a "Specialist company according to AwSV“. 

Since the AwSV entering into force on the 1st August 2017, this specialist company obligation is effective with work, for example, setting up, internal cleaning, repairs or decommissioning on a heating oil tank with a volume more than 1,000 litres.

You can find all detailed specifications about our heating oil tanks in our product catalogue

For the determination of the accessories required, the following applies: For the installation of the 1st tank, you need a basic installation kit. If you want to install another tank next to it, you need an extension kit. The installation one behind the other requires a connecting kit and a corner kit is needed for an L-installation.

The nominal volume specifies the maximum filling quantity to be achieved when excluding the safety criteria. With the effective volume on the other hand, this is the actual filling volume of a heating oil tank system. 

The effective volume is calculated based on the nominal volume when considering the limit value encoder switch-off time, maximum line length of 20 metres and a a backflow reserve of at least 100 litres. The so-called differential amount may exceed the usual 95% depending on the tank version.

During the installation of tank batteries, there are a few things that have to observed. Such as regulations that explicitly specifies the wall clearances: 

  • Single-row batteries must have a minimum distance of 40 centimetres from one side of the container, for all other containers a minimum of five centimetres. There are currently no requirements for the distance to the ceiling. 
  • For two-row batteries (multi-block system), there must be a minimum distance of 40 centimetres on the front side and two longitudinal sides, for the other sides, a distance of 5 cm. The distance to the ceiling is 20 cm above the heating oil tanks. 
  • The distance can be reduced to the safety stipulations of a single-row system using a ceiling clearance of 50 cm and respective leak indicator.

Yes! In out product brochure, you will find a visualised representation of the wall clearances on page 8.

Yes as our new WERIT safety tanks can be combined space-saving. Different block as well as corner installation are not a problem. Due to modern oil condensing boilers, the consumption is reduced and the volume of the tank system can also be reduced. 

Old heating oil tanks

I have an old heating oil tank and need spare parts? 

Even a very good heating oil tank needs spare parts after several years. For this, WERIT offers diverse filling, withdrawal and venting lines for all tanks
produced since 1970. For the precise determination of the respective article, we recommend that you fill in our dimensional sheet for single-row or multi-block tank systems. 


Dimensional sheet - Single-row installation

Dimensional sheet - Multi-block system 


In 99% of the cases, a leak in the line system does not originate from the sealing element used. Plastic tanks have a setting behaviour where lines have to be widened due to the rigid on-site assembly. This results in the seal appearing to be too small and can no longer completely seal. 

In addition, you as a customer have the certainty that a new line functions immediately and the time you have to use can therefore be reduced to a minimum. 

Using our leaflet "Technical reasons, withdrawal of heating oil tanks from service", you can conduct a self-check with the reasons listed therein. 

Being a manufacturer, we recommend a technical expert inspection in accordance with the German AwSV (ordinance on facilities for the handling of substances hazardous to water). You can find more information as well as technical experts in your region at www.sicherer-ö (only in German). 


Technical progress has not stopped, even with heating oil tanks. The plastic tanks from WERIT are double-walled and thus equipped with an integrated collection tray. This allows you to do away with the brickwork and protective paint coating in your tank room. The Techno safety tanks are also equipped with the Q3 seal. 

For you as customer, this has more benefits:

  • Odour trap 
  • Dimensionally stable 
  • UV stabilisation 
Residential areas

The requirements in water protection areas are very different depending on the authorities. We recommend that you clarify this in advance with the water authorities below. Basically, the double-walled safety tanks from WERIT can also be installed in water protection areas. 

Yes, that is not any problem at all. Our double-walled safety tanks in the flood version are approved up to a flooding height of 3.5 metres. This is the maximum possible height that can be reached with a heating oil tank made of plastic. 

Yes, our double-walled safety tanks can be installed in earthquake zone 1 - 3. The matching tank is available from WERIT depending on the earthquake zone. A respective anti-slip mat is required additionally for underneath the safety tank.