Solar Water Heating
Available in direct/indirect systems
There are two main factors to consider when purchasing a solar water heating system; water quality and prevalence of frost in your area. Both factors are relevant to the type and performance of a solar water heating system best suited for your building.
There are two types of systems; a direct system and an indirect system:
1.) Direct System
In this system, the water is circulated and heated directly by the collector panels. To function properly, the ambient air temperature must not fall below 4˚C and the water quality must be good. The open/direct system is not generally suited to frosty winter conditions.
2.) Indirect System
In an indirect/closed system, the building water does not circulate through collector panels. Instead heat is transferred indirectly without coming into contact with the water supply via a heat exchange fluid in the collector panels (glycol). Ideally the collector panels and the tank should be situated on the roof right next to each other, resulting in minimal heat loss. Split systems are an option for those folk who do not want the tank exposed on their roof. The indirect/closed system is well suited to climatic conditions where frost is prevalent and the water quality is inconsistent.