A chemical and/or biochemical system (1) having at least one reaction vessel (3) in which chemical and/or biochemical reactions may take place, the temperature of the reaction vessels being cycled between at least a highest predetermined temperature and a lowest predetermined temperature, the system comprising a thermal mount (4) for receiving the reaction vessel (s), the thermal mount being thermally coupled to a first, thermally conductive side of a thermoelectric module (5), a second thermally conductive side of the thermoelectric module being thermally coupled to a heat sink (6) and being provided with a pair of electrical contacts (33) to which a pair of electrically conductive wires (34) is connected for coupling to a power source, characterized in that a flexible adhesive (31, 32) is provided between the first thermally conductive side of the thermoelectric module and the thermal mount and between the second thermally conductive side of the thermoelectric module and the heat sink, whereby the adhesive
