US Patent 7901517 Operating-phase-dependent control of a heat-recovery device in dishwashers

The invention relates to a conveyor dishwasher having at least one washing zone (6, 7), at least one rinsing zone (8, 9) and a heat-recovery device (13) with a suction-extraction means. The dishwasher also comprises a drying zone (11). Openings (17, 18, 19, 20, 21) are provided for the suction extraction of air from the dishwasher. The overall quantity of the exhaust-airstream (24) can be varied by means of closing elements (25, 26, 27, 28), in dependence on the operating state of the dishwasher, by virtue of the openings (17, 18, 19, 20, 21) being completely or partially closed or released.