Up to now, gas furnaces have used fixed default settings in order to control the process of combining air and gas. But because fluctuations in the combustion process are not taken into account, the result is not always optimal. Lochschmied, who is the director of the application laboratory at Siemens’ Building Technologies Division in Rastatt, Germany, puzzled over this problem for a long time. "Since the market for gas furnace components is very sensitive to costs, I had to find a solution that doesn't get expensive," Lochschmied says.

He developed a control system, complete with the corresponding measuring circuits, that continually monitors and regulates the composition of the air-gas mixture. To accomplish this objective, the system uses an ionization sensor, a component that has been used for decades in practically all gas furnaces. In the past, this monitoring electrode has only measured whether the gas is burning. To this end, an alternating voltage is applied to it, and the electric current that flows through the flame is measured. By means of a special evaluation of this data, the new system developed by Lochschmied can also calculate whether the air-gas mixture is ideal. This mixture can vary a great deal and it can also change over time as a result of fluctuations of the gas composition or the air temperature, for example, or also because of the structural properties of buildings. The new system recognizes these factors and regulates the gas valve and the fan in the best possible way in accordance with the external influences.

This new technology, known as Sitherm Pro, is used in a number of control systems from Siemens and will be incorporated as a standard feature in gas furnaces from other manufacturers beginning in 2009. As a result of the optimized gas-air mixture, the gas heating system can be adapted much better to existing temperature control systems. "Up to now, the furnaces haven't been realizing their full potential in combustion. In the case of conventional control mechanisms, heating operation throughout the whole year requires a setting that's incompatible with the best possible energy use because of changing conditions," says Lochschmied. This is no longer necessary with his invention. In addition, the manufacturers of gas furnaces can reduce the number of furnace variants they have had to offer in the past for the different types of gas. The development periods for new gas furnaces have also been shortened considerably, because when control systems incorporating Lochschmied's technology are used, there are far fewer occurrences of typical "teething troubles" like undesired noise during operation.

Lochschmied studied electrical engineering at the University of Karlsruhe, Germany, where he gained his doctorate. With his nine inventions, the 46-year-old holds already 57 patents for Siemens.