| 20110289674 | HEAT EXCHANGER - 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. | 12-01-2011 |