Viessmann Vitoligno 300-C Installation And Service Instructions Manual page 30

Installation sequence
Connections on the heating water side
Making the safety connections
Safety equipment block installation instructions
Install the safety lines.
Minimum cross-sections
Output
Boiler
6 to 18 kW
8 to 24 kW
11 to 32 kW
13 to 40 kW
16 to 48 kW
Note
The connection between boiler and expansion vessel
must not be interrupted by shut-off devices.
Information regarding the safety valve
Equip boilers with a safety valve that is type-tested to
TRD 721 [or local regulations] and is marked accord-
ing to the system version.
Notes on installing the safety valve
■ In the event of water escaping, ensure that none of
the water runs over the boiler.
The supply line and discharge pipe for the safety
■
valve must not be fitted with shut-off devices.
■ The supply line and discharge pipe for the safety
valve must not be fitted with reducers.
■ The discharge pipe must discharge with a steady fall
and free cross-section into a funnel with stench trap.
■ The discharge pipe must not include more than 2
bends and must not be more than 2 m long.
If lengths of more than 2 m are necessary, use pipe-
work of the next larger diameter. Lengths over 4 m
and more than 3 bends are not permitted.
■ The drainage line from the wastewater funnel must
have at least twice the cross-section of the connec-
tion size of the safety valve.
Electrical connections
Routing cables
!
Please note
Incorrect wiring can damage the appliance.
■ Cables/leads must never touch motors or hot
parts.
■ Keep cables/leads away from rotating or mov-
ing parts.
Use the cable ties supplied.
■
Route cables so that they do not hinder any
■
maintenance work.
30
(cont.)
Pipe to the expansion ves-
sel
DN 15 (R )
½
DN 20 (R )
¾
Permiss. operating pres-
sure
Test pressure
Safety valve
Inlet connection
DN 15 (R )
½
Check the fittings on the heating water side for leaks
and tighten if necessary.
1. Open the cover of the control unit enclosure.
3 bar (0.3 MPa)
4.5 bar (0.45 MPa)
Discharge pipe
DN 20 (R )
¾