Connecting The Secondary Circuit; Electrical Connection; Preparing The Electrical Connections - Viessmann Vitocal 300-G Series Installation And Service Instructions Manual

Installation sequence
Making the hydraulic connections

Connecting the secondary circuit

1. Equip the secondary circuit on site with an expan-
sion vessel and safety assembly (in accordance
with DIN 4757).
Fit the safety assembly to the on-site line in the
heating water return.
2. Connect secondary lines to the heat pump
( 42 mm).
7 ≥
!
Please note
Mechanically loaded hydraulic connections
lead to leaks, vibrations and appliance dam-
age.
Connect on-site lines so that they are free of
load and torque stress.
!
Please note
Leaking hydraulic connections lead to appli-
ance damage.
Check the internal and on-site hydraulic
■
connections for leaks.
In the event of leaks, drain off liquid via the
■
drain valve. Check the seating of seal
rings. Always replace displaced seal
rings.
■ Ensure the diaphragm grommets at the
hose outlets are seated correctly. Seal
hose outlets with sealing tape if necessary.
Position of diaphragm grommets for
hoses: See page 46.

Electrical connection

Preparing the electrical connections

Cables
■ For cable lengths and cable cross-sections, see the
following tables.
For accessories:
■
Cables with the required number of cores for exter-
nal connections.
Prepare an on-site distribution box.
Danger
Damaged wiring insulation wiring can lead to
serious injury from electrical current and result in
appliance damage.
Route cables so that they cannot touch very hot,
vibrating or sharp-edged components.
16
(cont.)
3. Fill and vent secondary circuit.
Observe additional information regarding filling and
venting: See page 49.
4. Thermally insulate lines inside the building.
Note
Ensure the minimum flow rate, e.g. by means of an
■
overflow valve: See "Specification" from page 109).
■ In underfloor heating circuits, install a temperature
limiter on site to restrict the maximum temperature of
the underfloor heating system.
Danger
Incorrect wiring can lead to serious injury from
electrical current and result in appliance dam-
age.
Take the following measures to prevent drifting
of wires into the adjacent voltage area:
■ Route LV leads < 42 V separately from cables
42 V/230 V~/400 V~ and secure with cable
>
ties.
Only strip the minimum of insulation from
■
cables as close as possible to the terminals
and bundle tightly to the corresponding termi-
nals.
■ If 2 components are connected to the same
terminal, press both cores together in a single
wire ferrule.