Solar heating system heat collector unit - has double-walled cross tubes between header tubes, for air circulation

摘要

The heat collector for a solar heating system consists of two header tubes which may be of rectangular section, with a series of double walled tubes welded between them at right angles. The heat exchange medium which is circulated through them, can be air. The tubes are connected to an external circuit which includes a circulating fan, and a primary coil which transfers heat to a secondary coil. The air circulates through the inner tube of the transverse tubes. The space between the inner and outer tubes is under vacuum.