In the frame of the EU-funded sCO2-HeRo (supercritical carbon dioxide heat removal) project a heat removal system, based upon a Brayton cycle using supercritical CO2 as working fluid, is currently under investigation. The system should be able to work as a self-launching, self-propelling and self-sustaining decay heat removal system to be retrofitted to existing light water reactors. In case of an accident in a nuclear power plant with the combined initiating events of a station blackout and the loss of the ultimate heat sink this additional heat removal system will transfer the decay heat from the reactor core to the diverse ultimate heat sink, e.g. the ambient air. The system consists of a turbine, compressor, generator, compact heat exchanger and a gas cooler. Since the turbine of the turbo-compressor-system (TCS) provides more power than it is needed for the compressor, the system is self-sustaining and the excess electricity of the generator can be used for auxiliary devices of the power plant. To demonstrate the feasibility of this system, a small-scale demonstrator unit will be attached to the PWR glass model at Gesellschaft für Simulatorschulung (GfS), Essen, Germany. The components of the system will be designed, manufactured and experimental investigated within the sCO2-HeRo project. To determine the design of the compact heat exchanger for the glass model application, which is the objective of the Institute of Nuclear Technology and Energy Systems (IKE), experimental investigations on heat transfer between condensing steam and sCO? were performed in the SCARLETT laboratory. Based upon these experimental results, the compact heat exchanger was designed, manufactured, tested and delivered to GfS.