A fluid heater apparatus supplies heat to wash fluid via a continuous, labyrinthian flow path in a thermally conductive body. A heat source is disposed in the thermally conductive body for imparting heat to the body. Fluid flowing through the thermally conductive body substantially envelopes the heat...http://www.google.es/patents/US6912357?utm_source=gb-gplus-sharePatente US6912357 - Fluid heater
