Slant/Fin VHG-100-CH, Installation And Service Manual

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E93.1901EN032 Installation and Service Manual SlantFin VGH-CH / CO
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Gas pipe connection
The gas supply piping must conform to all local codes and regulations and/or National Fuel Gas Code, ANSI
Z223.1/NFPA 54. Pipe size running to the appliance depends on the length of pipe, the number of fittings and the
maximum input requirement of all gas appliances in the residence. See the gas sizing table below for help when
sizing the gas connection. For information on propane sizing consult your local propane gas supplier.
Schedule 40 Black Steel Pipe in Cubic Feet of Natural Gas per Hour.
(based on inlet pressure less than 2 psi, pressure drop of 0.3 W.C. and specific gravity 0.6)
Nominal Pipe
Size (In)
¾” 1” 1¼” 1½” 2”
Length (ft)
10 273 514 1060 1580 3050
20 188 353 726 1090 2090
30 151 284 583 873 1680
40 129 243 499 747 1440
50 114 215 442 662 1280
60 104 195 400 600 1160
70 95 179 368 552 1090
80 89 167 343 514 989
90 83 157 322 482 928
100 79 148 304 455 877
G
AS LINE CONNECTION
Consult the gas code to determine gas pipe size. It is required to install a manual shutoff gas valve in front of the
gas pressure regulator to make sure that the gas line can be closed in case of maintenance. The entire piping
system, gas meter and regulator must be sized properly to prevent pressure drop greater than 1" W.C. as stated
in the NFPA54. If you experience a pressure drop that is greater than 1” W.C., the regulator or gas line is
undersized.
The boiler requires a nominal value of 7” to 10” W.C. of gas pressure when using Natural gas and 11 to 13” W.C.
when using LPG; this will be available at the boiler gas valve inlet at maximum boiler firing rate. See the technical
specifications datasheets (paragraph 3.3) for minimum and maximum allowed gas pressures.
When an in-line regulator is used to drop gas pressure from 2 psi to 0.5 psi, it must be located at least 6 feet from
the boiler.
A minimum 1” diameter flex hose is required if flex gas hose will be used. Ensure that the gas line connection to
the appliance does not exert any force or pressure on the gas valve.
Create an installation layout in such a way that the piping does not interfere with the vent pipe, or any other
serviceable components.
The appliance must be installed in such a way that the gas ignition system components are protected from water
(dripping, spraying, rain etc.) during installation, operation and servicing.
No appreciable drop in line pressure should occur when any unit (or in the instance of a cascade installation when
all of the installed units) lights or runs. Use common gas line sizing practices. Make sure the gas pressure is within
specification during all conditions. Always use a pipe-threading compound. Apply sparingly to all male threads,
starting at two threads from the end. Over-doping or applying dope to the female end, can result in a blocked gas
line.
Table 7.1