Oil condensing boilers

Solution advantages

  • Increased efficiency and reducing emissions
  • Reducing demand for heating oil
  • Future-proof for use with solar energy and biofuels
  • Suitable for modernisation in existing buildings and new buildings, especially in remote areas and those not connected to gas networks

High efficiency

Modern condensing appliances are designed to use virtually the entire energy content of the fuel – the so-called higher heating value. Compared to standard and low-temperature technology, condensing devices also process the heat of condensation of the water vapour contained in the exhaust gas. Oil-fired condensing boiler technology thus achieves the highest efficiency with the lowest fuel consumption and minimum emissions.

Optimum use of fuel

Heating oil contains hydrogen which, on combustion, is turned into steam. When the exhaust gases from the combustion process are cooled, the steam contained in them condenses and the heat from the condensation process can be used. The flue gases must be cooled to below the so-called “dew-point temperature”, in order for them to condense. The dew-point temperature is dependent on the hydrogen content of the fuel and hence on the steam content of the flue gases.

With “extra-light” (EL) heating oil the dew-point temperature is about 47°C. By using the latent heat of condensation, the efficiency of a heating system can be significantly improved. In practice this results in the production of 0.5 to 1 l of condensate per kg of heating oil. Because of the relatively low temperature of between 45 and 50 °C of the resultant flue gases, flues for their removal can be made of plastic tubing. Modern condensing boiler technology can therefore extract energy from the fuel being used in the most efficient way.

Quality heating fuel

Low-sulphur heating oil (heating oil EL), which conforms to laid-down standards, is a quality fuel, ideally suited to the requirements of condensing boiler technology and demonstrates several essential advantages over normal heating oil. Noxious substances in the flue gases are reduced to a minimum and the condensate does not need to be neutralised. Moreover, low-sulphur heating oil burns very cleanly and makes for consistently good heat transfer in the boiler. This results in boilers which demonstrate continuously high levels of efficiency and a high degree of reliability, consequently reducing the maintenance requirements for boilers and burners.

Combining renewable energies

The oil condensing technology can be easily combined with a solar thermal system. The solar collectors support the domestic hot water preparation as well as partly contributes to meeting the space heat demand. The combination of a solar thermal system with an oil-fired heating system reduces oil consumption by 10–20%.

Moreover, liquid biofuels (produced from biomass) are already used for heating, being added to conventional fuel. They have a high energy density and can be burned without almost any residue or pollutants using modern combusting technology. One example is the so-called “bio-heating oil”, a low-sulphur heating oil, to which at least three percent by volume of a liquid fuel from renewable resources is mixed. Bio-heating oil can significantly help to reduce the demand for mineral oil, reduce greenhouse gas emissions and conserve resources. However, sustainable cultivation of raw materials and the most efficient use of the fuel are prerequisites for such benefits. Extensive research has been undertaken to facilitate safe use of liquid bio-fuels in heating systems across Europe.

Floor-standing oil condensing boiler
Floor-standing oil condensing boiler