If a lot of condensate flows back into the feed water container at high temperatures, this produces relaxation steam that cannot be used. If a relaxation steam heat exchanger is connected to the ventilation pipe of the feed water container, then the energy released can be used to heat softened water for other consumption.
For example, 100% condensate return flow and a return temperature of 160°C will lead to approx. 12% of the output being lost as relaxation steam. This output can be used via the relaxation steam heat exchanger.