Cooling Mode - Viessmann Vitotronic 200 Operating Instructions Manual

Appendix
Terminology
(cont.)
Note
With the Vitovent 200-W, Vitovent 300-C and
Vitovent 300-W, passive heating is not possible.
Air flow rates
In order to prevent any negative or positive pressures
developing in your rooms, the flow rate of the supply
air must exactly match the flow rate of the extract air.
Your contractor regulates these air flow rates during
commissioning.
Regulating the humidity and carbon dioxide con-
centration (CO concentration)
2
If a CO /humidity sensor (accessories) is installed in
■
2
one of your rooms, the ventilation unit can adjust the
air flow rate subject to the humidity and/or carbon
dioxide concentration (CO
■ If a humidity sensor (accessories) is installed in the
central extract air duct, the ventilation unit can adjust
the air flow rate subject to the humidity of all rooms.
The humidity and carbon dioxide concentration can
only be controlled in the "Ventilation program".
Frost protection for the heat exchanger in the ven-
tilation unit
Heat recovery transfers heat from the extract air to the
incoming outdoor air. This causes the extract air to
cool down, which in turn leads to condensate forming
in the heat exchanger. At low outside temperatures,
condensate can freeze on the heat exchanger. Heat
recovery is reduced. The worst-case scenario is that
the ice damages the heat exchanger.
Frost protection with electric preheating coil:
■
To prevent ice forming on the heat exchanger, the
outdoor air can be preheated by an electric preheat-
ing coil before it enters the heat exchanger. Some
ventilation units have an electric preheating coil pre-
fitted at the factory. For other units, your contractor
will install an electric preheating coil in the outdoor
air duct.
■ Frost protection without electric preheating coil:
If your ventilation unit does not have an electric pre-
heating coil, the air flow rate will be reduced in order
to protect the heat exchanger, if necessary until the
fans come to a standstill.
■ Defrost functions: Only with Vitovent 200-C
Your contractor can set various functions to defrost
any ice that may have formed on the heat
exchanger: e.g. the outdoor air flow rate can bypass
the heat exchanger and/or the supply air flow rate
can be reduced. In addition, the electric preheating
coil (accessories) can be switched on.

Cooling mode

See "Heating mode/cooling mode".
92
) of this room.
2
Note
With frost protection, the indicated ventilation level
may deviate from the ventilation level selected. The
ventilation level displayed is adjusted to reflect the
reduced air flow rate brought about by the frost protec-
tion function.
Only with Vitovent 300-F: supply air heating via
heating circuit 1 (ventilation heating circuit)
If a hydraulic reheating coil (accessories) has been
installed in your ventilation unit, the supply air can be
heated by the heat pump. The outdoor air/supply air
preheated in the heat exchanger of the ventilation unit
is reheated via the hydraulic reheating coil of the heat
pump.
In such a case, set the room temperature and time
program for central heating via the menu for heating
circuit 1.
Note
The level of heating output that can be transmitted via
the ventilation heating circuit is only minimal. Using
supply air heating as the sole heat source is therefore
only recommended for highly insulated buildings (e.g.
passive houses).