Holmberg S., Molin F., Myhren J.
Bibliographic info:
RoomVent 2004, 9th international conference in University of Coimbra - Portugal, 5-8th september 2004, pp 4, 7 Fig., 1 Tab., 4 Ref.

Rising energy prices have contributed to the development of heat pump-based heating systems in Sweden. Low flow temperature in the secondary heat distribution system to rooms is a requirement for energy-efficient systems. This increases the thermal efficiency of the heat pump and decreases thermal losses in the distribution system. Flow temperatures in water-based systems for heat distribution in buildings have been decreased from 55C to temperatures around 30C. This is to maximize the efficiency of heating systems that are based on heat pump technology. Different technical solutions have been suggested to guarantee space-heating requirements with low temperature difference between heating units and ambient air. Floor heating has in many cases been considered a good option, and the popularity of such systems has dramatically increased. Complicated installation work, moisture problems and slow thermal control with floor heating are reasons enough to find alternative low-temperature units for heat distribution in rooms. This may result in a combined heating and ventilation system that operates with forced convection.