The invention relates to a method for heating, in particular of highly viscous products, and a device for performing the method, wherein the product is pre-heated to a first temperature T1 in a first step with at least one product/water heat exchanger section with water as the heating medium, wherein the water cools down, is further heated to a second temperature T2 in a second step with at least one product/product heat exchanger section 2a with the product as a heating medium, wherein the returning product serving as heating medium is cooled down, and is then further heated to a third temperature T3 in a third step with at least one product/water heat exchanger section 3a with water as the heating medium, wherein the water cools down and wherein the heated product is then recirculated as heating medium for heating the product.
