Filling Connection; Making The Safety Connections; Low Water Indicator - Viessmann VITOLADENS 300-T Installation Instructions Manual

Connections on the heating water side
The flow and return pipes with the heat
exchanger connection can be fitted to
the r.h. or l.h. side of the boiler, subject
to where the heat exchanger is installed
(see page 11).
Connect all consumers, so that the heat
exchanger will receive a heating water
flow in any operating condition.

Filling connection

Fill the system via the fill valve that is fitted to the return connector pipe (see
page 16).
Service instructions

Making the safety connections

Installation instructions, safety
equipment block
Install the safety lines.
Permiss. operating pressure: 3 bar
Test pressure:

Low water indicator

Tests have verified that the low water
indicator stipulated by EN 12828 is not
required.
Note
■ Connect the heating circuits and DHW
cylinder to the common flow and
return.
■ Do not connect any consumers to the
remaining connectors at the back of
the boiler.
Minimum cross-sections
■ Safety valve inlet connection
33 and 40 kW: DN 15 (R ½)
50 kW:
■ Safety valve discharge pipe
33 and 40 kW: DN 20 (R ¾)
50 kW:
■ Line to the expansion vessel
4 bar
33 to 50 kW: DN 20 (R ¾)
Note
Equip boilers with a safety valve which is
type-tested according to TRD 721 and
which must be marked in accordance
with the relevant system version.
(cont.)
DN 20 (R ¾)
DN 25 (R 1)
19