Drainback system for commercial solar-thermal systems

Vaillant’s auroFLOW commercial solar-thermal drainback system is designed for buildings that tend to require hot water throughout the day when the building is in use. The system allows the solar fluid to fully drain from the collector and into the discharge vessel in the solar drainback module as soon as the heat demand in the cylinder is met. When heat is again required, the solar fluid is pumped back up to the collector.

Because the solar-thermal system does not stagnate, the solar fluid does not degrade as quickly. There is also no need for an expansion vessel.

All components are contained within the module.

For systems requiring more than 12 collectors, up to four collector arrays can be cascaded using the Vaillant VRS 620/3 control.