Connections On The Heating Water Side; Boiler With Low Water Cut-Off - Viessmann VITOLIGNO 300-C Installation And Service Instructions Manual

Installation

Connections on the Heating Water Side

Legend
A Low water cutoff
B Air vent
C Temperature and pressure gauge
D pressure relief valve
E Sediment faucet
F Bushing 1½ in. to ½ in. NPT
G Bushing 1½ in. to c in. NPT
H Bushing c in. to e in. NPT
I Nipple c in. to 1½ in. NPT
J Street elbow ¾ in. NPT
K Tee ¾ in. NPT
L Cross 1½ in. NPT
Note: The connection between boiler and expansion
tank must not be interrupted by shut-off devices.
58
Vitoligno 300-C Installation/Service
Performing a boiler pressure test
The boiler must be leak tested before being placed in
operation. Before boiler is connected to piping or electrical
power supply, it must be hydrostatically pressure tested.
1. After installing safety devices (see previous page),
install temporary cap on ¾ in. x 2 in. nipple.
2. Cap supply, return and drain connections (where PRV
is installed).
3. Connect ½ in. garden hose to boiler fill valve at
the bottom of the boiler and fill boiler slowly until
pressure gage indicates max. working pressure
45 psig (3 bar).
4. Maintain pressure for 15 minutes. During time of
pressure testing, do not leave boiler unattended.
5. Inspect all pipe joint connections and safety devices
with a flashlight for leaks. A lower manometer
reading than 45 psig (3 bar) usually indicates loss of
water due to leakage. All leaks must be repaired.
6. After 15 minutes, release water pressure from boiler
by opening boiler drain valve slowly, remove caps
from supply and return connections as well as ¾ in.
cap from 2 in. nipple, and install pressure relief valve
immediately instead of ¾ in. cap.
7. After boiler has passed pressure test, proceed with
the installation.
Maximum boiler operating pressure
Installing the low temperature protection package
The low temperature protection package must be installed
prior to connecting the boiler to the heating system.
Refer to installation instructions for low
temperature protection package
Connecting heating system
Flush heating system thoroughly prior to connecting boiler
Proper piping practice
Support piping by proper suspension method. Piping
must not rest on or be supported by boiler. Use moderate
amount of dope. Use an approved pipe sealant or teflon
tape when connecting the following installation fittings.
2 imperfect threads

Boiler with low water cut-off

Do not install an isolation valve between boiler and low
water cut-off.
Follow the installation instructions of the
low water cut-off from the manufacturer.
For low water cut-off connection to the boiler see page 43.
45 psi (3 bar)
Leave 2 threads bare