Connecting A Heating/Cooling Circuit, If Required; Electrical Connections; Routing The Cables To The Wiring Chamber - Viessmann VITOCAL 242-G Installation And Service Instructions Manual

Installation sequence
Hydraulic connections

Connecting a heating/cooling circuit, if required

The connection is made via the NC-Box (accessories).
For surface cooling systems (e.g. underfloor heating
circuit, chilled ceiling), provide an on-site contact
humidistat (24 V ).
–

Electrical connections

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.

Routing the cables to the wiring chamber

Cables:
Required cable length inside the appliance plus dis-
■
tance to wall:
2.25 m
■ Height of wall outlet:
2100 mm (see "Technical guides for heat pumps")
22
(cont.)
Installation instructions for contact humidistat (24 V
Install in the coolant flow of the room to be cooled. If
■
necessary remove parts of the thermal installation in
order to provide direct contact with the pipe.
■ Connect to plug F11 on the control and sensor PCB.
■ If several rooms with different relative humidity are
part of the cooling circuit, fit and connect several
contact humidistats in series.
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.
< 4
2 V
4 0
0 / 2
3 0
V
Fig. 18
):
–
400/230 V
< 42 V