WP1.E6 / THEORETICAL EVALUATION OF PROMISING SYSTEM: Combisystem Unit with Integrated Gas Auxiliary Heater

SUMMARY This solar combisystem concept is developed based on the experiences of the IEA-SHC Task26 /Weiss, 2003/, the ALTENER project “Solar Combisystems” /Ellehauge, 2003/ and investigations on the needs of the Danish market of solar heating systems. The evaluated system is not yet on the market, although it has been tested in the lab and is currently being undergoing field trials. It should be considered as still under development. There are plans to make it simpler, based on the results of the field and lab trials. Certain features have not been described in detail due to constraints from industry. The reference system that it is compared to is a standard Danish combisystem with external boiler and a hot water tank containing two heat exchanger spirals, one for the solar collector loop and one for the boiler loop. An external heat exchanger can transfer solar heat from the solar collector loop to the space heating system.