Active and passive solar pre-heat systems

摘要

Solar hot water pre-heat systems fall into two basic cat-egories — active and passive types — with numerous subcategories. A passive solar DHW pre-heater is also known as a breadbox heater or batch heater. It is essentially a large (30- to 40-gal.), glass-lined storage tank that is built into a super-insulated, triple-glazed box mounted directly on the roof of the building being served. The advantage is that it's simple in design with only one moving part, the water.