Integration of heating mode into ventilated cooled beam.

Nowadays the ventilated cooled beam is one of the most popular air-conditioning system, e.g. in Scandinavia and Central Europe. With such beams, it is possible to create high-quality indoor climate conditions, including thermal comfort and a low noise level within reasonable life-cycle costs. The beam is suitable for spaces with a high cooling requirement, low humidity load and relatively small ventilation requirement. Typically, the beams are used in offices and conference rooms. Although the beam system is quite popular and well-known, there is still limited experience in using these beams for primary heating. The main objective of this paper is to present the results of a study to determine the heating power that can be achieved with the beams. The study comprised several tests carried out in laboratory conditions. In the laboratory measurements, the heating capacity, temperature gradient of the room, and the air velocities were analyzed when the parameters were the temperature of the inlet water and the flow rate of the supply air. The results obtained from the study, show that it is possible to create comfortable indoor conditions with the beams even during winter conditions. The measured air-flow velocities were lower than 0.2 m/s at all the measurement points. An inlet water temperature of 40 °C gives a reasonable temperature gradient in the room of under 3 °C. At the same time, the average air velocity in the occupant zone is under 0.1 m/s.