Making optimal use of solar heating

New Logasol SAT-WZ midi heating energy control system ensures efficient integration of solar systems in multi-family houses with up to 30 apartments

For some years now, central solar systems have been successfully used as complete solutions for the central heating of buildings. The heart of this new technical standard is a fully pre-assembled hydraulic unit that combines separately operated heat generators – generally an oil or gas boiler and a solar system – into a single system. Until now, central solar systems were usually designed for buildings with between 20 and 200 housing units. Logasol SAT-WZ midi has been developed for multi-family houses with up to 30 apartments by Buderus, a brand of Bosch Thermotechnology.

Logasol SAT-WZ midi consists of three sub-assemblies and a buffer storage tank available in different sizes. It is comprised of three modules. The “Solar” module is designed for a collector area between ten and 45 square metres. The “Heating circuit / primary feeding / buffer tank filling and draining” module is suitable for a maximum rated heating load between 20 and 140 kW. The “Domestic water heating” module can handle rated outputs of 90, 130 and 170 kW. All components are fully pre-assembled and pre-wired for particularly easy installation. The fitter only has to establish the hydraulic, electrical and outside sensor connections. Thanks to its standardised design, the Logasol SAT-WZ midi system is suitable for new buildings as well as for the modernisation of heating systems.

In addition to hygienic continuous flow domestic water heating technology with energy-saving legionellae prevention, the main advantage of this complete solution is the fact that it controls the filling and draining of the buffer storage tank. A patented hydraulic and control system ensures the optimal use of solar energy in combination with a conventional heat generator, which results in slightly longer boiler operating times and a lower number of burner starts. While conventional solar systems merely supplement the heating system, Logasol SAT-WZ midi acts as an integrated intelligent control unit for all connected heat generators. As a result, solar power is consistently used as the primary source of energy.

Connecting the hydraulic and control lines of the solar system and the boiler system, the central solar system handles the entire heat energy management. The Logasol SAT-WZ midi uses its measuring and control functions to feed the solar energy into the system where the most savings can be made based on current consumption and weather conditions. In addition, it measures the conventional heating, circulation and domestic water circuits to efficiently adjust the system whenever required.