Why does the bath heat up above the ambient temperature when the circulator is not switched on?
Every circulator incorporates a circulating pump, which ensures thorough mixing of the bath liquid inside the bath and also pumps the bath liquid through an external circuit. The electrical energy taken up by the driving motor passes as thermal energy into the liquid, which leads to a slow temperature rise inside the circulator up to the so-called intrinsic temperature. The intrinsic temperature depends on the pump output, the insulation of the circulator, and on the bath liquid used. The intrinsic temperature of a heating circulator can sometimes be as high as 70°C or more. On the Lauda Ecoline circulators, the intrinsic temperature is only slightly above the ambient temperature if one of the lower five pump output steps is selected. Without cooling, the circulator can only be operated above the intrinsic temperature. The data in the literature refer only to water as bath liquid and to an ambient temperature of 20°C. With more viscous bath liquids and at higher ambient temperatures, t
