Local and district heating for heating and drinking water
Integrated insulation and contact protection of hot components through PU housing
Nowadays, anyone who wants to switch to district heating or have a defective heat transfer station repaired has to reckon with long waiting times and increased costs due to cumulative supply and personnel bottlenecks. The situation is further aggravated by special designs, which are necessary in many places due to limited space and varying customer requirements. To eliminate these problems, ewers Heizungstechnik GmbH develops heat transfer stations in a practical modular system. In this way, the individual modules of the ec compact station, which with up to 50 kW is designed to meet the needs of detached and semi-detached houses, can be optimally adapted to the conditions on site. All components are standard parts that can be supplied at short notice and can be replaced and maintained just as quickly if required. All variants of the ec compact station have a space-saving design, so that even particularly tight spaces are no problem. The precisely fitting PU housing also provides integrated insulation without thermal bridges and at the same time protects against accidental contact with hot elements.
According to the German Association of Energy and Water Industries (BDEW), district heating use by private households and housing associations in Germany has increased from around 49 billion kWh in the previous year to 55 billion kWh in 2021. Rising fossil fuel prices and the increasing expansion of networks in residential areas are driving this upswing in district and local heating. “But a conversion usually entails long delivery and thus waiting times,” knows Thomas Pollmeier, managing director of ewers Heizungstechnik GmbH. “Because depending on the available space and the individual needs of the users, the heat transfer stations must always be designed individually.” For this reason, ewers has set itself the goal of developing a comprehensive standard program that can be flexibly designed for different framework conditions and requirements, such as technical connection conditions (TABs) or the integration of a drinking water heating system. On the one hand, the concept simplifies the design work itself. On the other hand, it enables the manufacturer to keep the basic components, which can be combined with each other, in stock at all times, thus guaranteeing short delivery times of no more than 14 days.
Variable modular system with effective insulation
“Combining the widely varying customer requirements in one system caused us a lot of headaches,” Pollmeier reports. “Our solution is now a modular system made of standard components that can be implemented in numerous designs.” With the ec compact station for smaller to medium performance requirements, a choice can be made between direct and indirect connections, different hydraulic variants, one or two heating circuits, and various types of drinking water heating. Only corrosion-free and durable materials are used for the individual modules, such as gunmetal for molded parts and stainless steel for connections. Precisely designed heat exchangers and control valves enable efficient heat transfer in the smallest possible space. The high-performance ec compact station with up to 50 kW and a maximum temperature range of 135 °C is suitable for detached and two-family houses.
The high energy efficiency of the heat transfer station is made possible not only by the optimally designed components but also by the PU housing. As an integral part of the ec compact station, the precisely fitting and close-fitting thermal insulation made of polyurethane reliably prevents air movements and the resulting thermal bridges. “This means that less energy is lost, which helps significantly to save costs in the long term,” explains Pollmeier. “In addition, the electrical components are protected from overheating or mechanical influences. Furthermore, hot components can no longer be touched accidentally, which prevents injuries.” Since the hood can be easily opened and the parts underneath removed and installed with standard tools, the heat transfer station can be quickly maintained and – thanks to the compatible module selection – upgraded just as easily.
Different drinking water heating processes for optimum design
The ec compact station is offered in three basic versions: with storage tank system (ec.1), storage tank charging system (ec.2) and flow-through system (ec.3). The ec.1 version has a particularly simple as well as robust design and heats the drinking water within a storage tank, which enables a low price level. The ec.2 has a slightly more sophisticated technology that achieves lower return temperatures due to efficient heating of the water outside a stratified tank. The ec.3, on the other hand, meets the highest hygienic demands at the lowest return temperatures, as it produces hot water only when needed and does not store it. “All three variants can be adapted to individual needs in each case thanks to the modular system,” says Pollmeier, “for example with different heating circuits for a radiator and/or underfloor heating as well as for domestic hot water heating.” In addition, the temperature spectra can be configured, for example.
“Those who require a higher output, e.g. for residential or office complexes, can alternatively fall back on our er frame stations with et drinking water heating,” Pollmeier adds. “These were also developed according to the modular principle with storage, storage charging or flow-through systems and can be designed for up to 1,000 kW.” To support optimal network operation on the utility side, both the ec compact stations and the er frame stations are digitally networkable. Via the monitoring function of the ewers Digital software, the user can also flexibly monitor his data. The manufacturer also offers digital commissioning and maintenance services for the heat transfer stations.
Further information is available on the Internet at www.ewers.de
Based in North Rhine-Westphalia, ewers Heizungstechnik GmbH manufactures heat transfer stations and develops high-quality as well as reliable products in the fields of district and local heat transfer stations, drinking water heating and heating systems as well as heat and cold insulation. Since its foundation in 1963, ewers products have contributed to an ecological and sustainable energy supply. In 2022, ewers was awarded the Sigel TOP 100 as one of the most innovative companies in the German SME sector, and next year the company will celebrate its 60th anniversary. ewers currently employs around 75 people at two locations in Germany.