RBI Gas boilers - Gas Supply Piping

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GAS SUPPLY PIPING
Check the boiler/water heater rating plate to make sure
that the boiler/water heater is for the type of gas that
will be used. If it isn’t, do not connect the boiler/water
heater to the gas supply. Gas supply piping must be in
accordance with the National Fuel Code, ANSI Z223.1-
latest revision or applicable provisions of the local
building codes. Canadian installations must comply
with CAN/CGA B149.1 or .2 Installation Code. Failure
to comply with this warning can result in extensive
property damage, severe personal injury or death!
 e Futera Fusion comes from the factory ready to be piped to
the gas supply. If for any reason the boiler/water heater is not
for the type of gas available at the installation site, call your RBI
representative to resolve the problem.
A minimum gas supply pressure of 2 in, 51 mm, WC
natural or propane and maximum 14 in, 356 mm
WC natural or propane, must be available at the safety
shuto valve inlet with the unit(s) operating, and not
to exceed a maximum of a (1.0 in WC) drop when
 ring from minimum input to full load of the supply
line and all appliances running.
Table 11 should be used to ensure that the gas supply piping is sized
properly. If more than one appliance is supplied by the same supply
pipe, the piping must be sized based on the maximum possible
demand. Do not neglect the pressure drop due to pipe   ings. Table
10 should be used in conjunction with Table 11 to ensure that the
gas supply piping has the capacity to meet the demand.
Figure 14 depicts the proper way to connect the boiler/water
heater to the gas supply piping.  e manual shut-o valve MUST
be installed in the supply piping. It should be installed 5  , 1.5 m
above the  oor where required by local codes. Provide a sediment
trap at the bo om of the vertical section of the gas supply pipe
upstream of the gas controls.
A ground joint union should be installed between the boiler gas
controls and the supply piping. Each of these items are needed to
ensure long life and ease of servicing. Always use a pipe sealant
that is suitable for use with LP gas.
Table 11 Gas Pipe Capacity
Maximum pipe capacity in ft
3
/hr based on 0.60 specifi c gravity gas
at a pressure of 0.5 psig or less and a 0.3 in WC pressure drop.
Nominal
Iron Pipe
Size
Pipe length in feet
10 20 30 40 50 60 80 100 150
Maximum gas volume of pipe, (ft
3
/hr)
1" 520 350 285 245 215 195 170 150 120
1 1/4" 1050 730 590 500 440 400 350 305 250
1 1/2" 1600 1100 890 760 670 610 530 460 380
2" 3050 2100 1650 1270 1270 1150 990 870 710
Note: Multiply the gas volume by 0.62 for propane fl ow capacity in ft
3
/hr.
Multiply the propane fl ow capacity by 2500 Btu/ft
3
to determine
the propane Btu/hr capacity for a given pipe size and length.
Table 12 Equivalent Pipe Length Chart
Nominal
Iron Pipe
Size
Type of pipe fi tting
90° Elbow Tee
1
Gate Valve
2
Gas Cock
2
Equivalent pipe length, (ft)
1" 2.6 5.2 0.6 1.5
1 1/4" 3.5 6.9 0.8 1.9
1 1/2" 4.0 8.0 0.9 2.3
2" 5.2 10.3 1.2 3.0
Notes: 1. For fl ow through branch.
2. For fl ow at full open.
Figure 14 Gas Supply Piping