The increasing availability of sensor data leads to new integration problems in Cyber Physical Systems (CPS). In this paper we present an automatable approach to model CPS systems with common Linear, Time-Invariant processes. We show how this approach can be used to model the thermal processes in a room as well as complex measurements like thermal comfort. We demonstrate our approach for a real building with numerous connected sensors and show how our semantic framework allows us to detect and diagnose abnormal thermal comfort. This can lead to not only an increase of occupant well-being but also to a reduction of energy use. Given that buildings consume 40% of the world's energy use we therefore also make a contribution towards global sustainability.