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Domestic ventilation system
The domestic ventilation system compri-
ses the central ventilation unit
Vitovent 300, an air duct system with
silencers for outdoor air/ventilation air
and extract air/exhaust air, as well as air
outlets for ventilation and extract air.
Fresh air enters the living rooms and
bedrooms via ventilation air apertures.
Stale air from rooms where moisture and
odours are created (e.g. kitchen, bath-
room, WC) is routed away via the extract
air apertures.
Heat recovery
The extract air is routed through a coun-
tercurrent heat exchanger for the pur-
pose of heat recovery. This preheats the
fresh outdoor air without coming into
direct contact with the stale extract air.
To ensure heat recovery is as effective
as possible, keep windows and doors
closed while heating. This also applies to
doors to ancillary and cellar rooms that
are not included in the domestic ventila-
tion scheme.
Bypass
Appliances with a maximum air flow rate
of 300 m3/h and 400 m3/h have an inte-
gral temperature-controlled, motorised
bypass damper.
Subject to the outside temperature, this
bypass switches automatically between
operation with and without heat recov-
ery.
In operation without heat recovery, all
the outdoor air is routed past the heat
exchanger, so that in summer the cool
outdoor air is not heated by the extract
air.
However, a bypass cannot achieve the
same efficiency as active cooling.
Frost protection circuit
With heat recovery, the extract air is
cooled in the countercurrent heat
exchanger, which creates condensate.
The frost protection prevents the extract
air side of the countercurrent heat
exchanger from icing up as a result of
this condensate.
With this frost protection, the outdoor air
flow rate is regulated subject to the out-
door air temperature and the pressure at
the heat exchanger. Initially, the outdoor
air flow rate is reduced to defrost the heat
exchanger.
Introductory information
Device description
5592 694 GB
