Viessmann VITODENS 200-W B2HE 85 Installation Instructions Manual page 20

Boiler Connections
Piping Connections
B2HE 85, 120
B2HE 150, 199
Legend
A Gas connection to boiler
B Union
C Accessible manual gas shutoff
D Drip leg
E Boiler gas control switch
IMPORTANT
Max. gas supply pressure: 14 "w.c.
½ psig = 14 "w.c.
WARNING
Never check for gas leaks with an open flame.
WARNING
Exposing boiler gas pressure regulator and gas valve to
extreme pressures renders warranty null and void.
20
(continued)
Vitodens 200-W B2HE 85, 120, 150, 199 Installation
Gas connection and piping (continued)
1. Make gas connections in accordance with codes
CAN/CSA B149.1 or 2 in Canada.
In the United States, use the 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 boilers 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)..................................7 ¾ in.
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.
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 boilers in
the residence. No noticeable gas pressure drop in the
gas line must occur when any unit (or combination of
units) lights or runs.
Gas piping pressure test
When performing the gas piping pressure test, ensure the
following requirements are met.
1. Isolate the boiler from the gas supply piping system
using the individual manual shutoff valve during
pressure tests equal to or less than ½ psig (14 "w.c.)
2. The boiler and its individual shutoff valve must be
disconnected from the gas supply piping system
during any pressure testing of that system at test
pressures in excess of ½ psig (14 "w.c.)
3. Perform leak test. Use approved liquid spray solution
for bubble test. Ensure that no liquid is sprayed on
any electrical components, wires or connectors. Do
not allow leak detection fluid to contact gas valve
regulator or regulator vent opening.
4. Correct any and all deficiencies.
5. Remove air from gas line.