Characterization of radiant systems for heating and cooling

Water based surface embedded heating and cooling systems exhibit peculiar features compared with other HVAC systems. Therefore, many studies have been developed defining how to design and test the components of these systems. Nevertheless, advanced technical solutions requires a deeper analysis of the performances both of the components and of the overall assembly. In the following study a low-thickness heating and cooling radiant module with a non-conventional geometry of the embedded piping layer points out some open issues. The thermal performance of this system have been measured inside a climatic chamber; tests are combined with simulations in order to set up numerical models, successively used for the optimization of the system. A test facility has been set up for measuring the performance of a full scale heating and cooling floor designed for industrial applications.Different alternative methods have been applied to measure the heat delivered to the conditioned environment. Among them, the well-known enthalpy balance is used as a reference. A new method, based on quantitative infrared thermography, has been developed in order to determine local heat fluxes, with centimetric spatial resolution on the surfaces. Results collected for two years by the different methods have been compared and analyzed. The comparison, applied both to wide and narrow surfaces, suggests some useful remarks on the characterization procedures derived from current standards.