Heat recovery
Cross-flow, counter-current heat exchangers are standard equipment for Zehnder ventilation systems. They are therefore capable of transferring the heat energy of the used air to the fresh air. This heat transfer takes place through thin plastic plates according to the counter-current principle. The heat recovery level is approx. 90%, which saves approx. 40% of the heating costs.
Humidity recovery
The relative humidity in the building is optimised by plate heat exchangers, which is ideal when the air is dry in winter. The water vapour from the humid exhaust air "condenses" and is taken up by a membrane. The recovered humidity and heat are transferred to the fresh air without any transfer of smells or microbes.
Summer bypass
Most Zehnder ventilation systems have a 100% summer bypass. It moves the exhaust air past the heat exchanger and thus prevents the supply air, which in summer is cooled down by the earth heat exchanger, from being re-heated by the warm exhaust air. This function can also be used during cool summer nights.
