Gas Supply Piping - RBI LCD Series Installation & Operation Manual

GAS SUPPLY PIPING

WARNING: 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!
The LCD 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 Water Heaters representative to resolve
the problem.
Note: A minimum gas supply pressure of 6 in,
152 mm, W.C. natural or 11 in, 279 mm W.C. propane
and maximum 14 in, 356 mm W.C. natural or
propane, must be available at the safety shutoff
valve inlet with the unit(s) operating.
Table 10 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 fi ttings. 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 16 depicts the proper way to connect the boiler/
water heater to the gas supply piping. The manual shut-
off valve must be installed in the supply piping. It should
be installed 5 ft, 1.5 m above the fl oor where required
by local codes. Provide a sediment trap at the bottom
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.
LCD INSTALLATION AND OPERATION INSTRUCTIONS
Table 10 - Gas Pipe Capacity
Maximum pipe capacity in ft
at a pressure of 0.5 psig or less and a 0.3" WC pressure drop.
Nominal
Iron Pipe
10 20 30
Size, (in)
Maximum gas volume of pipe, (ft
3 / 278 190 152
ʺ
4
520 350 285
1ʺ
1
1 / ʺ 1050 730 590
4
1
1 / ʺ 1600 1100 890
2
2ʺ 3050 2100 1650 1450 1270 1150 990
2 1 / ʺ 4800 3300 2700 2300 2000 1850 1600 1400 1130
2
3ʺ 8500 5900 4700 4100 3600 3250 2800 2500 2000
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
the propane Btu/hr capacity for a given pipe size and length.
Table 11 - Equivalent Pipe Length Chart
Nominal
Iron Pipe
90° Elbow
Size, (in)
Equivalent pipe length, (ft)
1ʺ 2.6
1 3.5
1 / ʺ
4
1
1 / ʺ 4.0
2
2ʺ 5.2
2 1 / ʺ 6.2
2
3ʺ 7.7
Notes: 1. For fl ow through branch.
2. For fl ow at full open.
CAUTION: Always use a wrench on the gas valve
body when making gas connections to it. Never
over-tighten the piping entering the gas valve body
or gas valve failure may result!
Figure 16 - Gas Supply Piping
3
/hr based on 0.60 specifi c gravity gas
Pipe length in feet
40 50 60 80 100
3 /hr)
130 115 105 90 79
245 215 195 170 150
500 440 400 350 305
760 670 610 530 460
870
3 to determine
Type of pipe fi tting
1 2
Tee Gas Valve Gas Cock
5.2 0.6
6.9 0.8
8.0 0.9
10.3 1.2
12.3 1.4
15.3 1.8
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150
64
120
250
380
710
2
1.5
1.9
2.3
3.0
3.7
4.5