Hermann Umweltservice GmbH, based in Pforzheim, is already in its third generation of business in the field of sewer cleaning, sewer TV inspection and leak testing as well as complete separator service. The family-owned company has always focused on sustainability in all areas of the company. "A key aspect of our sustainability strategy is to largely dispense with fossil fuels and heat with the highest possible efficiency," says project manager Daniel Hasler, summarizing the requirements for the heating system replacement. Together with Hoval, a hybrid system consisting of two heat pumps and a modern gas condensing boiler was developed to meet the needs. Since summer 2023, the 2,830 m² site, including a factory hall, offices, changing rooms and recreation rooms with showers and two residential units, has now been supplied with sustainable heat.

For the Hermann family, the heating system renovation represents a milestone in the implementation of the sustainability strategy. This is achieved by a combination of two Belaria pro 15 heat pumps and an UltraGas 70 from Hoval. Approximately 80 percent of the heating and hot water demand is covered by heat pumps and thus renewable energy. If the outside temperature drops and thus also the efficiency of the heat pump, the system automatically switches to gas heating. "The system is set up in such a way that we get the most economical and efficient maximum out of all heat generators and only then switch to another device," says Daniel Hasler, pleased with the efficient use of resources. Even in the event of maintenance or any failures, another of the three heat generators steps in directly, thus ensuring the supply of heat and comfort at all times.

In order for the company to be able to take advantage of all the advantages of the hybrid system, the complexity of the project had to be mastered. Together with the company Preuss Wärmetechnik from Karlsruhe, it was possible to optimally integrate all heat generators into the existing infrastructure of radiators, convection fans and underfloor heating. Each area now gets exactly the heat it needs and the heating system runs perfectly. The shareholders Johannes and Isabelle Hermann agree that the decision in favour of Hoval was exactly the right one: "Hoval reflects our values and the cooperation is characterised by respect, adherence to deadlines, professionalism, pragmatic solutions and, above all, a high level of humanity."