Low energy building simulation

The decrease of heat demand in low energy build-ings, very sensitive to solar and internal gains, and the development of new HVAC systems call for a reexam-ination of the usual modeling approaches in building simulation. A focus is brought on an air-to-water heat pump plugged to a radiant heating floor (RHF) by a hydraulic loop installed in a typical low energy dwelling. Using a RADTEST evaluated Modelica slab model, several floor thermal masses under four differ-ent control strategies are compared to determine their impact on HVAC system performances.