Viessmann Vitocal 350-A Installation And Service Instructions Manual page 96

Installation sequence
Electrical connections in the heat pump control...
For further information, see from
page 104.
Immersion heater EHE
Connection
Installation instructions, immersion heater EHE
Appliance
Immersion heater EHE
Note
Alternatively, an external heat source
can be installed on site for DHW heat-
ing.
External heat source
!
Please note
Protect the heat pump against
temperatures over 70 °C from the
external heat source.
Install a high limit safety cut-out
or take further measures if
required.
96
Connection Required parameters:
Parameter Ó setting
2X8.13 "DHW"
1X1.? ■ "Booster heater" Ó "Yes"
1X2.N
(see page 48)
Note
■ The switching contact to demand heat
from an external heat source in the
heat pump ("Ext. HS for DHW") is a
zero volt N/O contact that closes in
case of heat demand.
■ This contact can be subjected to a load
of 230 V~/4(2) A in case of an external
voltage supply. Never route low volt-
age via this contact; that requires an
on-site relay.
■ The boiler water temperature sensor in
the external heat source (identification
F20; terminal 3X1.4/3X2.4) must cap-
ture the average temperature of the
external heat source.
(cont.)