Dhw Heating - Viessmann Vitocal 300-G Installation And Service Instructions Manual

Preparing for installation
Function description in connection with the system . . .
Active cooling (AC) function
The AC-Box enables, together with a
suitable brine/water heat pump active
cooling (AC operation) and natural
cooling (NC operation). The AC-Box
is linked directly to the brine and DHW
circuit of the heat pump and enables
an external circuit reversal to actively
cool living areas in summer. The fol-
lowing can, for example, be con-
nected to the AC-Box: Fan
convectors, cooling ceilings/sails and
underfloor cooling. During NC opera-
tion, the heat pump remains switched
off; only the primary pump is switched
on.

DHW heating

In the delivered condition, DHW heat-
ing through heat pump takes priority
over the heating circuit.
Instantaneous heating water heater
An instantaneous heating water hea-
ter can be installed in the unit (acces-
sory, see separate installation
instructions).
Subject to the available mains, the
system may be supplied with either
230 V~ or 400 V~.
16
This operation prevails until AC
operation (active cooling with acti-
vated heat pump) becomes necessary
through an excessive cooling load. In
this case, the resulting heating energy
at the condenser is primarily used for
DHW heating or for heating swimming
pool water, and is secondarily stored,
as far as possible, in the ground for
the following winter.
The control unit switches the DHW cir-
culation pump OFF during cylinder
heating to prevent cylinder heating
from being impaired.
Protect the instantaneous heating
water heater via a separate connec-
tion.
The heat pump control unit regulates
this function.
(cont.)