Abstract: A device for detecting and signalising a leakage in a double-walled conduit system of a heat exchanger for heating fresh water by way of heat from waste water in the sanitary field as well as a heat exchanger including such a device. The device has an elastic element and a signalisation unit, wherein the elastic element is essentially liquid-tight and the signalisation unit is configured to generate an acoustic signal and the signalisation unit is activatable by way of a mechanical deformation of the elastic element.

Abstract: A heat exchanger for heating fresh water using heat from wastewater in a shower or bathtub. The heat exchanger has a drain pan, a heat exchanger unit that is arranged in the drain pan, and a distributing element for distributing draining wastewater over the heat exchanger unit. The heat exchanger unit has multiple tube portions that follow one another sequentially and are connected to one another by diverting portions. Each two horizontally running tube portions that follow one another and that are thus connected by a deflecting portion are arranged one over the other, and wastewater, which is dripping or flowing down, is sprinkled on or flows over the tube portions one after the other.

Abstract: A heat exchanger for a shower tray can be arranged in the bottom of the shower tray for the heat recovery from wastewater so as to heat fresh water. To this end, the heat exchanger has a planar cover plate as the drain surface over which the wastewater drains. The cover plate forms the bottom of the shower tray, over which a lid that can be removed without the use of tools is arranged as a tread plate. The heat exchanger preferably includes a distributor element, which is arranged for distributing the wastewater over the drain surface. The distributor element is preferably a retaining element, which retains the wastewater at an upper edge of the drain surface and forms an overflow along the upper edge.

Abstract: A shower tray having a heat exchanger that is arranged beneath the shower tray for recovering heat from waste water in order to heat up clean water, wherein a first heat-exchanger surface is in contact with the waste water and a second heat-exchanger surface is in contact with the clean water, and the first heat-exchanger surface forms the floor, or part of the floor, of the shower tray. The shower tray here is produced from one metal material and, in the region of the tray floor, beneath the shower tray, a base plate made of some other metal is fastened on the tray floor, so as to form a heat-conducting connection to the tray floor is formed substantially over the entire surface of the base plate. Beneath the base plate, tubes are connected to the base plate in an integral manner. The tubes form the second heat-exchanging surface.

Abstract: A heat exchanger for a shower tray can be arranged in the bottom of the shower tray for the heat recovery from wastewater so as to heat fresh water. To this end, the heat exchanger has a planar cover plate as the drain surface over which the wastewater drains. The cover plate forms the bottom of the shower tray, over which a lid that can be removed without the use of tools is arranged as a tread plate. The heat exchanger preferably includes a distributor element, which is arranged for distributing the wastewater over the drain surface. The distributor element is preferably a retaining element, which retains the wastewater at an upper edge of the drain surface and forms an overflow along the upper edge.