The thesis deals with energy-saving plumbing systems. It is divided into three parts: task analysis, applications theme on the building and experiment. In the first part are described the possibilities of saving water and energy in the plumbing systems. The second part contains a comparison of some variants of saving solution water supply system and sanitary drainage system at the hotel. Part of the experiment investigates the water consumption for washing hands in addiction: the pressure in the water supply system and the type of mixing valves.

Buildings account for up to 32% of the total energy use in different countries. Directives from the European Union have pointed out the importance of increasing energy efficiency in buildings. New regulation in countries like Sweden establishes that new buildings should fulfill regulations of Nearly Zero Energy Buildings (NZEB), opening an opportunity for new technologies to achieve these goals. Almost 80-90% of the energy in domestic hot water use is wasted from different applications with almost no use and with a lot of potential energy to be recovered. The present work studied the characteristics of greywater heat exchanger as a solution to recuperate heat from greywater to increase efficiency in buildings. This study explored the fluid mechanics involved in the vertical greywater heat exchangers, analyzing the falling film effect present in drain pipes and the effects of the secondary flow generated in the external helical coil. A heat transfer model from a theoretical approach was proposed and validated. In addition, this study explored the different variables influencing the economic feasibility of the technology and an economic analysis was performed. A theoretical comparison between a greywater heat exchanger application and a reference case without it was evaluated highlighting the importance of all the variables involved in the potential of implementation of the technology. The technology shows big potential in households with high water consumptions, especially with electric boilers.

The goal of this diploma thesis is the design of the sanitary installations and gas main in the pension for pensioners. The building has three floors above ground and one underground floor. The building will be covered with a hiped roof. On the first floor there is the technical background of the building, Reception and kitchen with dining room. The basement is located just below the kitchen and serves as a cloakroom for kitchen staff. The building will be designed to use as much non-potable water as possible in the form of rainwater, which will be collected from the roofs. The theoretical part deals with the use of non-potable water as operating water in buildings. The calculation and project part deals with the gravity sewer system, plumbing and gas main in the building.