22
Series 49
Installation, Operating & Service Instructions
111368-04 - 1/22
8
Gas Piping
1. Size gas piping. Design system to provide
adequate gas supply to boiler. Consider these
factors:
A. Allowable pressure drop from point of delivery
to boiler. Maximum allowable system pressure
is ½ psig. Minimum gas valve inlet pressure is
listed on rating label. Also see Table 8-1.
Figure 8-2: Gas Piping
Natural
Gas
Inlet Min
(in. wc.)
Inlet Max
(in. wc.)
Manifold
(in. wc.)
All Sizes
4.0
14.0
3.5
Table 8-1: Gas Pressure
B. Maximum gas demand. Consider existing and
expected future gas fired equipment (i.e. water
heater, cooking equipment, etc.)
2. Connect boiler to gas supply system.
A. See Figures 8-3 and 8-4 for gas manifold and
control assembly configurations.
B. Use methods and materials in accordance with
local plumbing codes and requirements of gas
supplier. In absence of such requirements,
follow
National Fuel Gas Code,
ANSI Z223.1/
NFPA 54.
C. Use thread compounds (pipe dope) resistant
to action of liquefied petroleum gas.
D. Install sediment trap, ground-joint union and
manual shut-off valve upstream of combination
gas valve (within 6 ft. of boiler). See Figure 8-2
E. All above ground gas piping upstream from
manual shut-off valve must be electrically
continuous and bonded to a grounding
electrode. Do not use gas piping as grounding
electrode. Refer to
National Electrical Code,
ANSI/NFPA 70.
3. Pressure test gas connection before placing boiler
3. Pressure test gas connection before placing boiler
in operation. Follow
in operation. Follow
National Fuel Gas Code, ANSI
National Fuel Gas Code, ANSI
Z223.1/NFPA 54
Z223.1/NFPA 54
..
DANGER
Explosion Hazard.
Do not use matches, candles, open flames or
other ignition sources to check for leaks. Failure
to comply could result in severe personal injury,
death or substantial property damage.
WARNING
Explosion Hazard.
• Failure to properly pipe gas supply to boiler
could cause improper operation or leaks of
flammable gas resulting in severe personal
injury, death or substantial property damage.
• Gas supply to boiler and system must be shut
off prior to installing or servicing boiler gas
piping.
!
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