A two-family house in Franconia was to be completely renovated in terms of energy and a controlled ventilation system with heat recovery should be integrated into the heating system. For this purpose, among other things, 16 m² flat-plate collectors for the collection of solar heat as well as an air-water heat pump with 18 kW heat output were provided. The requirements for the heating system of the house, which also houses an office, were divided into the supply of the underfloor heating (for approx. 240 m² of living space), the radiator (for approx. 110 m² of living space) and drinking water heating for 4 to 6 people. Of course, a hot water tank was also provided, which should be equipped with the necessary heat exchangers and of course be of a corresponding size.
The problem: access to the planned installation site, the attic, was typically restricted, so a factory-made container was out of the question. A Haase type T 410-14 hot water tank with a volume of 1,450 liters proved to be the technically and economically ideal solution. When fully assembled, this storage tank is 2.15 m high, but due to the on-site assembly, the insertion of the individual parts was not a problem.
The main arguments for the customer when choosing this hot water tank were the very low heat losses and the excellent layering properties of the Haase product.
Access to bring the individual parts of the hot water tank to the attic was only possible via a narrow staircase. 
The hot water tank is built in an attic. 
The installed hot water tank in the attic.
