Central ventilation is a system where ventilation occurs partially (System C) or entirely (System D) via a network of pipes and a ventilation group. The main feature of a central ventilation system is that the polluted air can be removed directly, so that it cannot spread through other rooms. Please remember that the inflow must always occur through dry rooms and the outflow through humid rooms in a central ventilation system.
By applying central ventilation in a home, you have the option to achieve controlled ventilation and therefore avoid undesired airflows. However, this does require an entirely airtight home.
Central ventilation system C:
Central ventilation system C means that the air supply occurs naturally, for instance via vents in the wall, and the air extraction occurs mechanically.
The air extraction can be demand-controlled, in order to optimise the comfort and ventilation requirements. Here, the ventilation unit is controlled by a presence sensor and/or (?) a domotic system, and a humidity sensor. The ventilation unit type C by Elek Trends (C1250) is fitted with a humidity sensor as standard. It continuously measures the extracted air and increases the flow temporarily if the humidity level becomes too high.
Central ventilation system D:
With a type D central ventilation system, both supply and extraction are done mechanically. The big advantage of this system is that is enables heat recovery. This happens with the use of a heat exchanger: the cold supply air is heated in the heat exchanger by the warm return air. This greatly reduces heat loss. The efficiency of a good heat exchanger is around 80-90%.
A system D is also called balanced ventilation, because ideally the total supply flow is equal to the total extracted flow.
The main advantages of this balanced ventilation with heat recovery are: