Switching On Central Heating / Cooling And Dhw Heating - Viessmann vitocal 300-g Operating Instructions Manual

Switching on central heating / cooling and DHW heating

You want to heat your rooms and have DHW available, or cool your rooms at high
outside temperatures.
Note
Central heating will only take place during the heating season. The heating season
is calculated from the difference between the outside temperature and the default
room temperature. The starting limit (heating temperature differential) that relates to
the outside temperature can be set by your heating contractor.
Cooling function
"Natural Cooling" (NC)
During the summer months the temper-
ature level of the brine or water circuit
can be used to cool the building "natu-
rally".
The natural cooling (NC) function is a
method of cooling buildings that saves a
considerable amount of energy.
All that is needed is a small amount of
electricity for the circulation pumps to
access the "cooling source" in the
ground.
The capacity of the natural cooling func-
tion cannot generally be compared with
that of air-conditioning systems. Natural
cooling provides no dehumidification.
The refrigerating capacity depends on
the temperature, which is subject to sea-
sonal fluctuations. Experience has
shown that the cooling capacity is higher
at the beginning of summer than at the
end.
Underfloor heating systems and con-
crete core tempering are available for
cooling the building; radiator heating
systems are unsuitable for this pur-
pose.
Start-up/shutdown
"Active Cooling" (AC)
Together with the heat pump, the AC-
Box (accessory) enables active cooling
(AC mode) and natural cooling (NC
mode). The AC-Box is linked directly to
the heat pump and enables an external
circulation reversal to actively cool living
areas in summer. The following can, for
example, be connected to the AC-Box:
Fan convectors, cooling ceilings/sails
and underfloor cooling. The active cool-
ing function has a greater capacity than
natural cooling.
■ If the cooling function is integrated into
a heating circuit, it is only activated
when outside temperatures are high.
■ The starting limit (cooling temperature
differential) that relates to the outside
temperature can be set by your heat-
ing contractor.
■ The cooling function will be enabled
via the room temperature if the natural
cooling function is designed as a sep-
arate cooling circuit.
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