Viessmann WB1A Series Installation And Service Instructions Manual page 20

Boiler Connections
Connections
(continued)
Gas connection and piping (continued)
Legend
Gas connection
Accessible manual gas shutoff
(factory supplied)
Drip leg
IMPORTANT
Max. gas supply pressure: 14 "w.c.
WARNING
The gas supply piping must be leak
tested before placing the boiler in
operation.
CAUTION
Ensure that gas piping is large
enough for all appliances in the
residence. No noticeable gas
pressure drop in the gas line must
occur when any unit (or combination
of units) lights or runs.
20
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1. Refer to current CAN/CSA B149.1 or
National Fuel Gas Code ANSI
Z223.1/NFPA 54, as well as local
codes for gas piping requirements
and sizing. Pipe size to the boiler
must be determined based on:
– pipe length
– number of fittings
– maximum input requirements of all
gas appliances in the residence.
IMPORTANT
Design piping layout in such a way that
piping does not interfere with
serviceable components.
2. Before connecting boiler to gas line,
install ground joint union, capped
drip leg and a manual equipment
shutoff valve. Valves must be listed
by a nationally recognized testing
agency. Make boiler gas connection
as shown on the left.
Gas connection (NPT)
. . . . . . . . . . . . . . . . . . .
3. Perform gas piping pressure test as
described in the following
subsection.
4. Identify shutoff valves as such with
a tab and familiarize
operator/ultimate owner of boiler
with these valves.
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